I've been wondering why they don't offer the 6 speed (auto OR manual) with the LS4...
GM has dropped the F40 6-speed manual transaxle from all domestic carlines. It is now only offered in Saab vehicles. Specs for the Saab F40 6-speed can be seen here: http://www.media.gm.com/us/...s/08_GME_F40_MU9.xls - It only has a maximum engine torque rating of 245 ft/lbs.
As far as the 6-speed auto is concerned, according to the GM media powertrain website the 6T70 is only rated for a maximum engine torque of 280 ft/lbs. Specs for the 6T70 6-speed auto trans can be seen here: http://www.media.gm.com/us/...tics/08_6T70_MH2.xls
But looking at a 1998 GM powertrain book I have here, I can see back in 1998 the 4T65-E was only rated for 280 ft.lbs. maximum engine torque.
But to answer your question, Will, I think the main reason why GM hasn't brought a better auto or even a manual transmission together with the LS4 is because they don't plan on keeping that engine very long. Word in the auto magazines says GM is going to be switching most of their cars over to rear-drive (except for the econo-boxes) and will be doing away with the hi-powered FWD cars soon.
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06:40 PM
Will Member
Posts: 14249 From: Where you least expect me Registered: Jun 2000
I thought the F40 was rated at 300 ftlbs? Oh well... another poor market assesment on GM's part. Honda can offer TWO models of the Accord with manual transmission... why can I not buy a Malibu with a manual AT ALL?
I thought the transmission load rating was based loosely on GVW or GCW... IE, a 70 series transmission could be used up to 7,000 lbs... and yet it has a torque rating of less than 300 ftlbs? GM is strange.
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08:12 PM
Apr 22nd, 2008
Rickady88GT Member
Posts: 10648 From: Central CA Registered: Dec 2002
I thought the F40 was rated at 300 ftlbs? Oh well... another poor market assesment on GM's part. Honda can offer TWO models of the Accord with manual transmission... why can I not buy a Malibu with a manual AT ALL?
I thought the transmission load rating was based loosely on GVW or GCW... IE, a 70 series transmission could be used up to 7,000 lbs... and yet it has a torque rating of less than 300 ftlbs? GM is strange.
In first gear, what is the highest out put tq at the highest rated input tq? Maybe the tq at the wheels is closer to 7,000 lbs?
Just found this thread, and I must say, what an incredible project! Some beautiful work there! I love the color combo and options chosen, too! If this car were a Notch, it'd be almost perfect, lol!
Nice job, guys!
------------------ ~Michael
"Your mileage may vary." '85 GT 4sp white - SOLD | | '85 2M6 Auto red - SOLD | | '84 2M4 bare chassis - SOLD Crap, I'm out of Fieros! Time to buy another!!
OKAY, Okay, okay....I've had my car back from Ryan for a little over 2 weeks now! I've gotten over the sheer thrill of having it back and can now provide an appropriately balanced report on Ryan's work and the performance of one of the first stock LS4 swaps into Fiero (now officially known as the 87'/05' Pontiac Fiero GXP!).
Ryan is the mutha-phukin' man! This swap looks like it rolled off the assembly line...probably even better!
Once I finally decide on what paint scheme I'm going with this fall, I will color match the engine cover to the paint job. But hell, one might argue to leave the engine cover off all together as tight and neat as it looks!
But there's something to be said, when people open up the rear deck lid and see the 5.3L V8 glaring at them and the "Ohhhh Sh*%!!" comments it creates. So the cover stays!
As a recap, beyond the engine swap which included the 4T65eHD TapShift tranny and custom paddle shifters, Ryan and I completely re-built the suspension down to the tie rods, springs, coil-overs, reconditioned control arms, control bars, polys, pretty much everything. Also installed rebuilt '88 Fiero calipers and 12" Corvette rotors, steel braided brake lines, and a custom cat back only exhaust with Corvette exhaust tips. A staggered 17/18 inch rim setup with 225/40 in front and 265/30 in the back with a lowered stance.
I drove it from Indiana back to Cincinnati, with a 102 degree fever sick as a dog, but with a smile on my face from ear to ear. My wife was following me and my 6 year old daughter was riding with me, so I didn't really open it up. Got alot of looks from passers by, especially whenever I zipped pass them at XX mph. No races or imaginary challenges that first road trip...thank goodness. With no mufflers, it's a bit loud but not ignorant loud. The only time its an issue is when I hear it clearly shift from 4 cylinders to 8 cylinders via the DoD setup and whenever I go from a point of acceleration to a coast...you clearly hear the gurgle-gurgle from the exhaust. If you've every gone boating, and witness some fancy cat put in his Twin V8 Cigarette Race Boat in the water...that's what it sounds like. One last Ohio e-check, at it's off w/ the cats and on with performance mufflers!! I can't be a "sleeper" car with the thunder of Thor crashing under the hood!!
Automatic shifts are deliberate and crisp. Using the paddles is actually kind of fun, but it kills my gas mileage as I tend to let the rpms run up to 3500-4000 before I shift versus it never goes above 2500 in auto unless I'm gunning it on the freeway, and even then at 80 mph (on roads with 75mph speed limits mind you) it's cruises just under 2000 rpm.
The only changes that probably needs to be fine tuned is to have the DoD shift much later in the power band, as I think it shifts a bit too soon. The other improvement is that while Ryan was able to turn off all the computer signals like ABS brakes, traction control, etc. the engine code has a default setting that whenever the tires have excessive spin, it throws the car in neutral, until you get back into it. So I've learned (learning) to ease into the launches with a slight tire chirp instead of stomping on it. Ryan is working with HP Tuners to fix both issues.
Brake power is awesome, much improved from the Grand Am kit that I had on the car originally...and the car comes alive like a bat out of hell. Mind you, my reference points are the previous 2.8L V6 that was in the car, and my 2000 Dinan 540 BMW 6 speed. This car out guns my big sedan with NO PROBLEM! Handling is very tight. I was expecting a really rock hard ride, but it's not bad at all unless I hit a pot hole. The one thing I must do before I put it on the track at Mid Ohio this summer is fix the play I'm feeling in the steering. I think it's about a 1/4 to 1/2 inch play in the steering, which is very noticeable at about 110 mph during a semi-aggressive evasive maneuver on the freeway. (Hypothetically speaking of course!). I've been searching this site to see if others have had issues with the rack and pinion steering (21 years old!!) and what the fixes could be, short of a total replacement...which might not be a bad idea given my "hypothetical" intended speeds.
At this point, I actually have been challenged once so far, by a 2006 Corvette, by the looks of the headlights. I pulled up on him. He gave me the "yeah, right dude" look. I threw the car in neutral and revved the engine (did I say I was challenged? I meant I challenged someone! ) He did the ole grip the steering wheel move and revved his vette' with the type of confidence that would soon be shattered. It was only a light to light thing, but I had to have put at least 1 1/2 car lengths between us and pulled in front of him, before he could recover. After he pulled up beside me, his dropped jaws told the whole story! My first kill! He probably didn't give it 100%, but a kill is a kill!!
So, you know I just had to get this car to a 1/4 mile drag strip, especially with all the controversy and debate we've had on my initial dyno results.
This past Friday, I took my Fiero GXP to Edge Water Sports Park just outside of Cincinnati for it's Test and Tune Night. http://www.edgewaterrace.com
While I've been on closed tracks with my BMW at least 7 times in the last 2 years, I have NEVER been to a drag strip. I'm nervous as hell, but excited about seeing what this car can do. I try to lower my expectations, as I don't want to set my expectations up too high as I knew I would have to deal with my street tires, not being able to hard launch the car, and trying to figure out how to respond to a light tree for the first time. I've watched PINKS on TV and blew a few brain cells on video games, but that's about it! I wasn't sure what to expect. I convince myself that if I an post low 13's I'd be content, and with practice and luck, maybe I could break into the 12's one day. I was probably more nervous about crashing the drag racing community, more than anything else! I won't go into the details here, but the community is awesome! Interesting....but awesome!! All walks of life, all ages, all levels of education, income, and levels of soberness...but all in love with cars. It was great!!
So....how did we do?
I was able to get three runs in. The first run matched me up against a 2006 Mercedes Benz CL500 Coupe. I was freaking out, until I saw that it wasn't an AMG car so I figured I had a decent chance of keeping up with him. His confidence level and that of his friends when they saw he was matched up with my white wolf in sheep's clothing was at an all time high! It took me a while to figure out how to stage the car so that the two white lights engaged on the tree (this only gave the Benz that much more reason to stick his chest out) but I finally figured it out, and settled into the start. Results? Kicked his ASS!!!!
R/T: .539 (he had a .442 R/T as a comparison) 60' : n/a my side wasn't working, but he had a 2.432 330: 5.510 1/8: 8.470 @ 83.76 mph 1000: 10.980 1/4: 13.128 @ 104.90 (the CL500 posted a 14.907 @ 96.88)
Recall, because of the code thing, I had to feather the start to avoid the shut down. But once it hooked, this car practically lept down the track! I'd do anything to run a 1/2 mile run, cause the car had plenty left and kept pulling the whole way. The sweet roar of the engine was only out gunned by the pounding of my heart against my chest! As I pulled back into line, my former nervousness quickly transformed into one cocky S.O.B.! As people walked by, I fielded all kind of questions regarding what the heck I had in this 21 year old "sheep"!
Race Two pitted me up against a 2005 BMW M3!! I won't lie, I was feeling a bit cocky still but the M3 driver and his crew actually had nerve to try to hide their giggling!! Oh, hell no! He gave his many friends high fives, and we pulled up into the start. Since I now knew I had a 13 second car, I had to wear my helmet. This actually gave the M3 a moment of pause! Of course, after the first run I immediately called Ryan to seek some coaching and driving tips, and report my results. He was very pleased, and was actually suprised I did so well for my first time at drag racing. We agreed to try to get aggressive with the next start to see if the track would hold my spin to a minimum and allow me to have a better launch. The M3 driver was smoking his tires like crazy. He was clearly no amateur, or so it appeared! I stomped...tires spun...car shut down! DAMMIT! I quickly got back into it, and to my disbelief...I was starting to quickly gain on the M3! Results? Caught his ass and beat him by .0618 seconds!!
R/T: 1.037 60: still racing on the side that's not working (he posted a 2.207) 330: 6.080 1/8: 9.037 @ 84.04 mph 1000: 11.537 1/4: 13.676 @ 105.33 (the M3 posted a 13.806 @ 102.59)
So, while I almost ran off the track cause I'm laughing so damn hard that despite a jacked up start, I still caught the M3 and beat him! But now I'm starting to get a little annoyed that I can't launch the car without fear of it shutting down on me. But before I could even get into feeling bad, as I get back in line for my final run, I'm met by crowds of people now even more curious than ever of what the hell I have as a power plant! They tell me the engine sounded awesome, and how the race announcer made a special point to call attention to the "little white Fiero with an attitude!". I spend the next 40 minutes answering questions and was even propositioned to sell my car twice. Of course there is NO AMOUNT of money that could get this car from me...at least not that night!! I thought to myself..I could get use to this!
My third and final run pitted me up against a late model Ford Thunderbird. It was an older guy, with race slicks in the rear and clearly something monsterous under the hood. At this point, I was happy to get away with two wins, so I was more focused on trying to launch without having the car shut down on me versus thinking I had a chance winning this one. The crowd was pretty thick at this point in the night, and I could easily see all the fingers pointing at my car as we pulled up. I think I was starting to get a bit of a fan club. This could really get addictive!! As I pulled up, I drove around the water to keep my tires dry, to see if that would do anything. Of course, the Thunderbird was laying all kinds of smoke and rubber. I tried not to focus on that, as I knew my goose was cooked on this race. Results? The Fiero GXP leaves it's first drag race UNDEFEATED!! About a 1/3 of the way down the track, he disappeared. I'd guess engine trouble or something. He finished, but well after the GXP!
R/T: .539 (the Thunderbird had a .233 R/T) 60: 1.895 ( I finally got on the side where the 60 ft worked!) 330: 5.442 1/8: 8.336 @ 84.80 mph 1000: 10.829 1/4: 12.961 @ 105.53 mph
Nearly 6 days later, and my voice is still hoarse from yelling and laughing so hard that I was able to break into the 12's at my first time at the track, with crappy R/Ts and having to feather my launches! That ride home was the best EVER!! I don't think I drove any faster than 60 mph the whole way home, but all windows and sunroof was open, just so I could hear the engine purrrr (or roar actually!).
So based on the 1/4 times, the calculators I've plugged the data into put the car at 272 HP at the wheels, and about 354 HP at the flywheel. This is consistent with the last Dyno reading Ryan made on the car. With a bit more experience, and fixing the wheel spin issue, there's no reason I shouldn't be able to get into the mid 12's on this car. I am one happy customer. It's not the fastest Fiero on the road...but it's a daily driver 1987 Fiero GT with one of the very first stock LS4s and it's all mine!!! [Ah-ha-ha-ha-ha-ha-haaaaa!]
Blkcofy
[This message has been edited by blkcofy (edited 04-25-2008).]
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10:20 PM
TiredGXP Member
Posts: 712 From: A cold, miserable place Registered: Jan 2008
I've never heard of the LS4 4T65e-HD popping into neutral, I suspect your launch issue is traction control kicking in. The stock tune controls wheelspin by both retarding timing and slamming the electronic throttle closed - it's even more severe when you are going around a corner and the differential score protection kicks in. Feels like something broke in the drivetrain, or you hit a brick wall .
Here's a shot of the TCS settings disabled in a 05 GXP; these settings might help your launch issues.
Due to the strong torque at low RPM of the LS4, the W-bodies have to launch at only part throttle - Load up the torque converter to 2000 RPM and slowly roll into the throttle. In a W-body it takes nearly 2 seconds to go WOT or the tires just light up, should be a bit better in a RWD application. The best 60' I've heard of in a LS4 W-body is 1.8 with drag radials and a sticky track, you're already there with street tires.
When you've had it long enough that you're not constantly mashing the loud pedal, you'll have to tell us what your mileage is like.
Cheers
[This message has been edited by TiredGXP (edited 04-24-2008).]
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11:23 PM
Apr 25th, 2008
Oreif Member
Posts: 16460 From: Schaumburg, IL Registered: Jan 2000
Nearly 6 days later, and my voice is still hoarse from yelling and laughing so hard that I was able to break into the 12's at my first time at the track, with crappy R/Ts and having to feather my launches! That ride home was the best EVER!! I don't think I drove any faster than 60 mph the whole way home, but all windows and sunroof was open, just so I could hear the engine purrrr (or roar actually!).
Sounds like the swap was completely worth the price of admission to me
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09:46 AM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
I've never heard of the LS4 4T65e-HD popping into neutral, I suspect your launch issue is traction control kicking in. The stock tune controls wheelspin by both retarding timing and slamming the electronic throttle closed - it's even more severe when you are going around a corner and the differential score protection kicks in. Feels like something broke in the drivetrain, or you hit a brick wall .
Here's a shot of the TCS settings disabled in a 05 GXP; these settings might help your launch issues.
Due to the strong torque at low RPM of the LS4, the W-bodies have to launch at only part throttle - Load up the torque converter to 2000 RPM and slowly roll into the throttle. In a W-body it takes nearly 2 seconds to go WOT or the tires just light up, should be a bit better in a RWD application. The best 60' I've heard of in a LS4 W-body is 1.8 with drag radials and a sticky track, you're already there with street tires.
When you've had it long enough that you're not constantly mashing the loud pedal, you'll have to tell us what your mileage is like.
Cheers
First I would just like to clarify, It is not kicking into neutral when this "limiter" is active. It's just closing the throttle momentarily when it sees exceesive wheel spin. ALL Traction Control parameters have been SHUT OFF in the programming via HP Tuners software. But I don't think this problem is related to traction control, because it acts much different than the '06 GXP I drove with traction control on. When the typical traction control system cuts in, it limits engine power but will still allow the car to accelerate (although at a greatly reduced rate). What blkcofy's car is doing is basically cutting ALL power, not just limiting it (effectively returning the engine to idle) for a moment and the car just seems to hang there in current speed and not accelerate at all. If you stay on the gas, after this second expires it lets the throttle open full again. However, if you lift off the gas and then get immediately back in it, then it will go without delay. (if the wheels spin again the limiter will kick in again) NOTE: If you are on a very grippy surface and the tires don't break traction, this limiter will NOT kick in. However, if you are on a very slick surface such as a smooth asphalt road in wet conditions, and the tires spin at will, then the system will kick in more quickly (as soon as tire spin is detected).
I believe what is going on here is some kind of abuse mode is kicking in. Now I will admit I didn't think to try adjusting the diff score parameter as you suggested, TiredGXP, -- I will have to get with blkcofy and try that.
Now there are some things I tried and HP Tuners suggested we try in the programming that did have some effect on what is going on with this "limiter". I went in and maxed out the ETC (electronic throttle control) opening limits in the programming myself and also tried some HP Tuners' suggestions for this same table. The abuse mode still kicked in after making these changes, however instead of closing the throttle to cut engine power, it LEANED OUT the fuel to very dangerous levels while the throttle blade stayed wide open. I didn't care for this happening because it could obviously hurt the engine, so I put the ETC limit tables back to stock for the time being. Looking thru the rest of the tables HP Tuners has to offer, I did find a limiter function that was "acceleration" based. I tried all sorts of different settings in these tables but nothing seemed to have any impact. (Keep in mind this is still a relatively new system in the aftermarket tuning community, so it may take a little bit of time before all necessary tables are found and defined in the tuning software).
Rest assurred I will find a solution to this problem; even if that means hooking the ABS computer up in some kind of limited capacity just to satisfy the needs of the ECM. In the meantime (while I am waiting on HP Tuners to come up with something), I have called on some of my contacts in the GM community to see if I can get any answers there. So I am still working on this problem outside of what HP Tuners is doing. And I do have a couple more things I would like to try, not only changing the diff score values as TiredGXP suggested, but also some other things that I thought of while staring endlessly at the tuning software. So I will have to get with blkcofy in the coming week or weeks to give these changes a shot.
Now that we got that out of the way, I have to congradulate blkcofy for his outstanding performance at the dragstip. That's a pretty big improvement to make during only 3 runs and his first time at a dragstrip ever. A best of 12.9sec @ 105mph is certainly no bad showing. And I'm sure with better traction on the launchpad, ie: some good prep work on the track surface (to prevent wheelspin), better numbers will come out of this car yet.
-ryan
------------------ power corrupts. absolute power corrupts absolutely.
The only changes that probably needs to be fine tuned is to have the DoD shift much later in the power band, as I think it shifts a bit too soon. The other improvement is that while Ryan was able to turn off all the computer signals like ABS brakes, traction control, etc. the engine code has a default setting that whenever the tires have excessive spin, it throws the car in neutral, until you get back into it. So I've learned (learning) to ease into the launches with a slight tire chirp instead of stomping on it. Ryan is working with HP Tuners to fix both issues.
So is this because of the modified computer, or do the stock LS4's have a permanent traction control that cant be turned off? With the electronic throttle, why does the ECM put the tranny in neutral instead of backing off the throttle? Does the shift from drive to neutral back to drive take less that .5 sec or was your run that much better with the exception of the "traction control"
------------------
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11:15 AM
PFF
System Bot
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
Originally posted by Rickady88GT: So is this because of the modified computer, or do the stock LS4's have a permanent traction control that cant be turned off? With the electronic throttle, why does the ECM put the tranny in neutral instead of backing off the throttle? Does the shift from drive to neutral back to drive take less that .5 sec or was your run that much better with the exception of the "traction control"
The transmission is NOT kicking into neutral. Read my prev post to yours about what is happening.
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11:17 AM
Rickady88GT Member
Posts: 10648 From: Central CA Registered: Dec 2002
The transmission is NOT kicking into neutral. Read my prev post to yours about what is happening.
Cool, I saw that after I posted. We must have been typing at the same time. I take forever to make a post
But that does bring up some more questions. You don't have the anti-lock brake module in the car do you? If not how would the ECM see the difference in wheel speed with out the wheel sensors? So traction control would seem not to be the problem because of the lack of inputs. More likely is the system is failing because of the missing components? I hooked up the anti-lock module in my S* swap and even had the four wheel speed sensors hooked up just to see if it made a difference (the four W body wheel bearings just plugged in). The car did not change that I could tel accept that with the wheel speed sensors disconnected the BRAKE light stays on permanently. Then one night the anti-lock module shorted out. It had water inside of it that had to of been there from the wrecking yard. I took out the module and the car ran exactly the same without it as it did with it.
I found a way to modify the front wheel bearings on my 88 to accept the wheel speed sensors. But the rear I have not figured out yet. I will at least have the front wheel speed sensors on my 5.3 swap. Then try to put the rear sensors in some how.
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11:45 AM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
Cool, I saw that after I posted. We must have been typing at the same time. I take forever to make a post
But that does bring up some more questions. You don't have the anti-lock brake module in the car do you? If not how would the ECM see the difference in wheel speed with out the wheel sensors? So traction control would seem not to be the problem because of the lack of inputs. More likely is the system is failing because of the missing components? I hooked up the anti-lock module in my S* swap and even had the four wheel speed sensors hooked up just to see if it made a difference (the four W body wheel bearings just plugged in). The car did not change that I could tel accept that with the wheel speed sensors disconnected the BRAKE light stays on permanently. Then one night the anti-lock module shorted out. It had water inside of it that had to of been there from the wrecking yard. I took out the module and the car ran exactly the same without it as it did with it.
I found a way to modify the front wheel bearings on my 88 to accept the wheel speed sensors. But the rear I have not figured out yet. I will at least have the front wheel speed sensors on my 5.3 swap. Then try to put the rear sensors in some how.
No I don't have the ABS module in the car; didn't have the opportunity to get that from the donor car either.
As far as inputs are concerned I can pull up some data on my GM Tech 2 scan tool that the ECM gives that actually displays non-driven wheel speed, and this always says "0mph" because no ABS module nor wheel speed sensors are present (there is no wheel speed sensor input to the ECM but rather the ECM gets that info over the Class 2 data circuit from the ABS module). But this doesn't seem to impact driving or engine power output as long as traction is good. I don't think the problem we are having has anything to do with the ABS system or Traction control. But rather I believe it has something to do with what TiredGXP brought up about the diff score or something else that is some kind of abuse mode or transmission protection that is acceleration-based.
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01:32 PM
TiredGXP Member
Posts: 712 From: A cold, miserable place Registered: Jan 2008
I haven't experienced what blkcofy reported except when differretial score protection kicked in with tire spin around a corner.
I was thinking about your comments about wheel speed, and noticed that all my wheel speed DTC's (C1207 to C1256) are set to "3-no error reported" from the factory. Whether that means that differences in wheel speed are actually ignored is another question that I don't have an answer to.
Just downloaded Version 2.22 of HPT yesterday, and noticed that transmission abuse mode tables have now appeared for the LS4, wonder what zeroing out the duration table will do for this issue, or have you already been there?
Since I still have a long-term plan to transplant a LS4 into a Fiero, I hope you lick this issue. Keep up the excellent work!
Cheers
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08:30 PM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
Just downloaded Version 2.22 of HPT yesterday, and noticed that transmission abuse mode tables have now appeared for the LS4, wonder what zeroing out the duration table will do for this issue, or have you already been there?
Since I still have a long-term plan to transplant a LS4 into a Fiero, I hope you lick this issue. Keep up the excellent work!
Cheers
Yea I just noticed that update as well and am downloading it now. Will see what more can be done with it.
-ryan
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10:20 PM
May 3rd, 2008
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
Just a quick update before I head up to the lake... I met with blkcofy today to try the new tune (with some changes per advice from TiredGXP) and that took care of the power cut issue. He can now burn all the tires he wants =P (at his own risk, of course!). I will go into greater detail exactly what was changed later when I have more time...
-ryan
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09:10 PM
May 5th, 2008
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
Ok, now that I'm back from the lake I have some time to explain what was done to blkcofy's tune.
TiredGXP suggested I disable the "Diff Score" function. According to most people I have talked to and many threads I have seen on the internet, this function serves to limit engine power if one drive wheel starts spinning much faster than the other wheel (like what you have on a 1-legged burnout). If this were allowed to happen, the pinion shaft that the differential gears ride on inside the differential could begin to score due to high loads and lubrication breakdown. One of the many flaws a front-drive/transverse transmission suffers from is the type of fluid it uses to lubricate internal parts. ATF has poor lubrication properties comparied to your standard 80-90w gear oil used in most rear axles (in RWD cars). And ATF doesn't hold up well when subjected to high loads or stress. Therefore GM built this function into many of their newer computers in an attempt to "save" the transmission. In this swap, the ECM shoudn't be able to determine if one drive wheel is spinning faster than the other because no individual ABS wheel speed sensors (nor the ABS computer) are installed. But I just went ahead and disabled it because it was easy to do.
I also went into the programming and disabled ALL of the Transmission Abuse Mode torque reduction functions. This is the function I believe was kicking in when the ECM saw the VSS output climb at very fast rates (IE what would happen when the tires were spinning). All of this seemed to do the trick in blkcofy's car.
Now with that problem solved I was also able to go in to the programming and max out the ETC (electronic throttle control) opening limit tables. The stock tables only allow the ETC to open to a certain point depending on engine RPM and desired engine TQ. Maxing out the values in this table made the engine seem more responsive off-the-line. I was not able to max these table values out before with the trans abuse mode kicking in because it caused the ECM to lean the fuel out severely instead of closing the throttle in an attempt to limit engine power (and that was very bad on the engine).
So needless to say the car does feel more responsive off the line now. Hopefully next time blkcofy goes to the track he can get some better traction on the launchpad which should allow him to post some better times.
-ryan
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01:34 PM
May 28th, 2008
Rickady88GT Member
Posts: 10648 From: Central CA Registered: Dec 2002
Darth, the way ECM detects it is by checking the speedo vs rpm. If that don't divide by the gear ratio, then one of the wheels are slipping, since the VSS sensor is actually on the pass side half-shaft. It also sees this, while cornering at low speeds (1mph drivers side, 5mph pass side, VSS sees 5mph but actually the wheels should rotate 3mph both, so +66% diff.)
There's also the tc that affects the ratio, but there is code to detect that somehow. I think it is by assuming on the TCC lock % that the HD box has.
Fog.
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05:20 PM
PFF
System Bot
Jun 1st, 2008
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
Darth, the way ECM detects it is by checking the speedo vs rpm. If that don't divide by the gear ratio, then one of the wheels are slipping, since the VSS sensor is actually on the pass side half-shaft. It also sees this, while cornering at low speeds (1mph drivers side, 5mph pass side, VSS sees 5mph but actually the wheels should rotate 3mph both, so +66% diff.)
There's also the tc that affects the ratio, but there is code to detect that somehow. I think it is by assuming on the TCC lock % that the HD box has.
Fog.
No, the VSS reads the reluctor wheel that is attached to the differential housing. So it has no idea which wheel is spinning faster in a one-wheel slip condition - for that it would need individual wheel speed sensors. But like I said in a previous post this "power cut" problem when excessive wheel spin was detected has already been solved -- it was the trans abuse mode kicking in and I disabled all of that in the programming and it took care of it.
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02:39 AM
Dennis LaGrua Member
Posts: 15438 From: Hillsborough, NJ U.S.A. Registered: May 2000
Great post and super neat install. Since the 3800SC will go out of production this year the LS4 seems like the engine that may take its place as the "in production" engine for a Fiero swap. I always favored the V6 in a Fiero but the light, compact state-of-the-art small LS4 V8 has changed my thinking. Only thing that might be difficult to live with though is the gas mileage. The engine has the DOD feature and mileage may be decent. How do you like the overall feel of the ETC?
------------------ 87GT - 3800SC Series III engine, 3.4" Pulley Flotech Exhaust Autolite 104's 4T65eHD 87GT - 3.4L Turbocharged engine, modified TH125H " I'M ON THE LOOSE WITHOUT THE JUICE "
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09:26 AM
BV MotorSports Member
Posts: 4821 From: Oak Hill, WV Registered: May 2001
Great post and super neat install. Since the 3800SC will go out of production this year the LS4 seems like the engine that may take its place as the "in production" engine for a Fiero swap. I always favored the V6 in a Fiero but the light, compact state-of-the-art small LS4 V8 has changed my thinking. Only thing that might be difficult to live with though is the gas mileage. The engine has the DOD feature and mileage may be decent. How do you like the overall feel of the ETC?
I've been driving one for three years now. The electronic throttle body works just fine. I know some people make a big deal out of it not being the same as a cable operated throttle, but I think that's BS. Tune the torque management properly and the throttle will do what your right foot commands. One plus for decluttering the engine bay is that cruise control on these engines is integrated into the ETC, so no add-on hardware is required.
The engine has an incredibly broad torque curve. According to GM, it delivers 90% of maximum torque between 1500 and 5600 RPM, so overall dirveability is excellent. My only beef is with the gearing GM chose for the 4T65E-HD. First is low enough that you light up the tires with any kind of aggressive throttle off the line; there's a big gap to second gear, which somewhat limits full throttle acceleration over 50 mph.
I'm waiting to hear what mileage BLKCOFY is getting in the Fiero. In a GP, at nearly 4000lb with driver, mileage is 16 in town and 27-28 (using US gallons) on the highway. I average around 22-23 in the summer and 20-21 in the winter. DOD makes 1-2 mpg difference on the highway, and adds virtually nothing in town as it does not operate in first or second gear or below 35 mph.
Cheers
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10:05 AM
Jun 2nd, 2008
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
I've been driving one for three years now. The electronic throttle body works just fine. I know some people make a big deal out of it not being the same as a cable operated throttle, but I think that's BS. Tune the torque management properly and the throttle will do what your right foot commands. One plus for decluttering the engine bay is that cruise control on these engines is integrated into the ETC, so no add-on hardware is required.
The engine has an incredibly broad torque curve. According to GM, it delivers 90% of maximum torque between 1500 and 5600 RPM, so overall dirveability is excellent. My only beef is with the gearing GM chose for the 4T65E-HD. First is low enough that you light up the tires with any kind of aggressive throttle off the line; there's a big gap to second gear, which somewhat limits full throttle acceleration over 50 mph.
I'm waiting to hear what mileage BLKCOFY is getting in the Fiero. In a GP, at nearly 4000lb with driver, mileage is 16 in town and 27-28 (using US gallons) on the highway. I average around 22-23 in the summer and 20-21 in the winter. DOD makes 1-2 mpg difference on the highway, and adds virtually nothing in town as it does not operate in first or second gear or below 35 mph.
Cheers
I've driven many ford and chrysler vehicles using their versions of ETC and I can understand why people don't like it. Just drove a 2008 Chrysler 300 with the V6 and ETC and it was VERY LAZY to respond to throttle changes commanded by my right foot. The Lincoln LS I drove a few years ago was almost as bad (haven't driven anything brand new from ford yet so they may have improved since then). But GM has done their homework when it comes to ETC on their engines. The engine response vs. your actions upon the gas pedal are phenominally quick. 95% of the people out there won't be able to tell a difference between a cable-op throttle system vs. the ETC used on the LS4. And after proper adjustments are made to the TQ MGMT and ETC tables in the computer programming as TiredGXP explained, I would say the remaining 5% wouldn't be able to tell a difference either.
As far as fuel economy is concerned, when I still had the car it seemed as though the DIC / trip computer was reporting the best instant fuel economy when I was driving down the highway at 50-55mph. But higher speeds effected a fuel economy penalty, and the DoD system disengaged after you surpassed about 80-85mph because the wind resistance load was too great on the car for the engine to stay in 4cyl mode and maintain that speed.
But in truth there are very few vehicles out there (DoD equipped or not) that are going to get as good fuel economy at 80mph speeds vs. that same vehicle at slower speeds. The 5.3 DoD engine has the potential to surpass 3800 SC fuel economy numbers as long as you can keep the speed in-check on the highway. But regardless, this 300+ HP LS4 engine still gets better fuel economy in a Fiero than ANY other GM V8 engine I have seen stuffed in a Fiero (at least according to owner reported MPG numbers). So I think the LS4 is probably your best bet for an engine swap if you want a V8, 300+ HP, and "good" highway fuel economy.
-ryan
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01:01 PM
BMTFIERO Member
Posts: 1187 From: Beaumont, TX Registered: Dec 2007
So, Blkcofy, now that you've had the car for a few months, how about a status report.
Are you still in love with the car? Have you had any problems? What sort of gas mileage are you getting? Do you have any regrets or is ther anything that you would do differently knowing what you know now?
Do you think that your LS4 swap will replace the 3800 S/C as the new engine swap of choice?
Thanks for doing such a good job on documenting your build and including so many pictures.
Good luck with the new setup. I hope it gives you years of pleasure and reliable service.
~Bob
------------------ "Its nice to be important. Its more important to be nice."
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01:47 AM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
So, Blkcofy, now that you've had the car for a few months, how about a status report.
Are you still in love with the car? Have you had any problems? What sort of gas mileage are you getting? Do you have any regrets or is ther anything that you would do differently knowing what you know now?
Do you think that your LS4 swap will replace the 3800 S/C as the new engine swap of choice?
Thanks for doing such a good job on documenting your build and including so many pictures.
Good luck with the new setup. I hope it gives you years of pleasure and reliable service.
~Bob
Not to speak for blkcofy, but here's what he has told me thus far. We had a problem come up where some trouble codes set for BOTH O2 sensor heater circuits. The presence of these codes disabled the remote start system (this also happens on the stock vehicles). I suspect that one of the heater circuits in one of the O2 sensors has gone bad and shorted out and is causing the problem (I've had this happen to me before). But I have not had time to get to the car to check it out myself because of pending projects. However, blkcofy discovered that his car no longer needs to be e-checked and he wants the get rid of the cats and install a muffler because it is a little loud for him. So within the next couple of weeks blkcofy is going to bring his car up to me to have the exhaust redone and at that time I will see what is going on with the O2 sensors (in the process of redoing the exhaust one of the O2 sensors will be getting deleted). So I will advise how everything works out when the exhaust gets redone.
-ryan
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02:18 PM
madcurl Member
Posts: 21401 From: In a Van down by the Kern River Registered: Jul 2003
OKAY, Okay, okay....I've had my car back from Ryan for a little over 2 weeks now! I've gotten over the sheer thrill of having it back and can now provide an appropriately balanced report on Ryan's work and the performance of one of the first stock LS4 swaps into Fiero (now officially known as the 87'/05' Pontiac Fiero GXP!).
Ryan is the mutha-phukin' man! This swap looks like it rolled off the assembly line...probably even better!
...
DANG!!! That is AWESOME!! That install looks fantastic Darth Fiero and your car is amazing blkcofy. I guess I won't be the first with an LS engine and a 4T65 tranny functional on the road after all - what a bummer.
DANG!!! That is AWESOME!! That install looks fantastic Darth Fiero and your car is amazing blkcofy. I guess I won't be the first with an LS engine and a 4T65 tranny functional on the road after all - what a bummer.
--Will
If things go as planned you want even be the first in Texas. I am trying to get my LS4 swap finished up in the next 2-4 months and have it on the road. But the wait will be worth it for you in the long run.
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06:42 PM
Will-Martin Member
Posts: 1164 From: DFW, TX, USA Registered: Aug 2002
If things go as planned you want even be the first in Texas. I am trying to get my LS4 swap finished up in the next 2-4 months and have it on the road. But the wait will be worth it for you in the long run.
I hear you man, I can't wait to see yours in action. I REALLY can't wait to ride in it... ><HINT HINT>< haha!
I guess I will just have to settle for the first Chop Top LS 4T65E.
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10:24 PM
Jul 15th, 2008
pavo_roddy Member
Posts: 4351 From: State with a city named Gotham Registered: Apr 2004
Great install, superb job done guys! Jus a couple quick questions for ya, hehe... Your paddle shifters are they mounted to the column or the wheel? In essence, do the shifters turn with the wheel? If so, does anyone know if they make column mounted paddles? Do they even make paddles that won't turn with the wheel?
edit to fix message....... ------------------ Me, I sell engines, the cars are for free, I need something to crate the engines in.... Enzo Ferrari....
Today they are called garage's, yesterday, they were stable's! Eric Jacobsen....
[This message has been edited by pavo_roddy (edited 07-15-2008).]
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07:27 AM
FierOmar Member
Posts: 1644 From: Glendale, California, USA Registered: Dec 2001
Great install, superb job done guys! Jus a couple quick questions for ya, hehe... Your paddle shifters are they mounted to the column or the wheel? In essence, do the shifters turn with the wheel? If not, does anyone know if they make column mounted paddles?
Great install, superb job done guys! Jus a couple quick questions for ya, hehe... Your paddle shifters are they mounted to the column or the wheel? In essence, do the shifters turn with the wheel? If so, does anyone know if they make column mounted paddles? Do they even make paddles that won't turn with the wheel?
edit to fix message.......
The paddle shifter setup purchased for this project is actually a machined housing that installs onto the steering column and then the wheel mounts directly to the housing. So yes the paddle shifters turn with the wheel.
Finished the fuel pump install (Walbro 255lph) and hooked up the fuel pressure regulator...
-ryan
Ryan, can any adjustable fuel pressure regulator be used for this setup? Also, would it be possible to use this type setup with the 7730 ECM? (Since fuel pressure does not vary as in the vacuum regulator type system)
Hugh
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05:58 PM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
Ryan, can any adjustable fuel pressure regulator be used for this setup? Also, would it be possible to use this type setup with the 7730 ECM? (Since fuel pressure does not vary as in the vacuum regulator type system)
Hugh
Sure, any aftermarket adj. FPR can be used in this system. In fact you can probably just buy a stand-alone adj. FPR with AN fittings on it already so you don't need to fool around with butchering one from a factory application.
You should be able to tune any ECM to work with a non-varying fuel system. The reason why GM used varying pressure fuel systems so many years was because it kept the pressure difference between the rail and manifold constant over the engine operating range; which made tuning easier. But you could just use a fixed pressure system and tune for it.
Will the 7730 ECM work with the LS4? I'm sure with enough work you could get it running -- but something will need to be worked out for the ignition system to get that to interface with the 7730 ECM. But why? The LS4 ECM is tunable now and is far more capable than the 7730 ECM.
Sure, any aftermarket adj. FPR can be used in this system. In fact you can probably just buy a stand-alone adj. FPR with AN fittings on it already so you don't need to fool around with butchering one from a factory application.
You should be able to tune any ECM to work with a non-varying fuel system. The reason why GM used varying pressure fuel systems so many years was because it kept the pressure difference between the rail and manifold constant over the engine operating range; which made tuning easier. But you could just use a fixed pressure system and tune for it.
Will the 7730 ECM work with the LS4? I'm sure with enough work you could get it running -- but something will need to be worked out for the ignition system to get that to interface with the 7730 ECM. But why? The LS4 ECM is tunable now and is far more capable than the 7730 ECM.
If the top of the regulator already installed is held in place by a snap ring then you may be able to use the adjustable regulator cover from the 8100 V8 regulator like the one I'm using. The regulators look similar from what I can tell in the picture. It would save the added effort of changing what is already a nice setup.
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06:59 PM
Nov 20th, 2008
kawana Member
Posts: 2329 From: Abbotsford, BC, Canada Registered: May 2007