I'm not saying it is amazing. But the post also doesn't say what engine is getting that boost.
it clearly said series2 3800, as it is a 2004 grand prix.
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I was just restating what was said in the thread, and pointing out that he broke a trans. Troyboy is putting out about 480whp through an F40 with no problems, but his is also cryoed.
And we dont know the driving habits or the clutch dynamics of troy's.
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I don't know what the reference to blowing up the autos, that fieroguru made, was about. I didn't see that in that thread. Maybe he knows the guy from another forum or something, where he was complaining about it.
It was there, but he detuned it severely from the "kept blowing up autos" power level. Cut the turbo size down, and turned the boost down 7psi.
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But this guy with the GP broke the trans twice doing the exact same thing, so it would be nice to know what exactly caused it. If it's the insane clutch, shifting at readline, and causing the rpm drop to put it right at the peak torque area when he lets out of the clutch, increased load, or something else. It's a thread about whether the trans has broken for anyone, and I figured people might want to see one broken. More info would be great, but I don't have any more.
It was clear that shifting into 4th, and letting the clutch out (turbo car, so you wont be shifting on top of full power) broke it. Combination of shockload and just too much power hitting the gears. There is little to nothing that is going to save your gears if they are just that weak.
OK, I obviously overlooked those parts. It also said he pulled 581 whp with the 4t65e.
Of course, I don't know why people keep quoting hp numbers when they talk about breaking transmissions. It's the torque and shock loading that does it.
And I doubt troyboy abuses his car like that, yeah, sure.
And I'm not sure how you could call https://www.fiero.nl/forum/Forum2/HTML/110249.html "not a transmission related failure"? "I just broke a second Getrag." seems pretty clear cut to me. Is there more info and pictures on what actually broke there?
Troyboy is putting out about 480whp through an F40 with no problems, but his is also cryoed.
But that guy has more brains that teststostone and rolls on custom wheel, has kids and so on. I am willing to bet that his car hasn't been driving hard since it has been on the road. And I am not talking hard to V-8 guys standards but to ripping the shist out of it to see what it can take.......I mean it has been on spirited 120 MPH runs as stated but hell a Ford Fiestia can do that with no issues....
Originally posted by MstangsBware: But that guy has more brains that teststostone and rolls on custom wheel, has kids and so on. I am willing to bet that his car hasn't been driving hard since it has been on the road. And I am not talking hard to V-8 guys standards but to ripping the shist out of it to see what it can take.......I mean it has been on spirited 120 MPH runs as stated but hell a Ford Fiestia can do that with no issues....
Yeah. And the people who constantly break things, seem to be the kind of people who like to constantly break things. If you just keep building everything stronger until it breaks, you're just going to keep breaking more and more expensive parts. I'm sure the 3800 kids are giddy that a 3800 was what put out the torque to break it, and it wasn't a V8. But a built ecotech would too if you always drive around like a pissed off teenager.
If anyone cares so much to know what the limits are, why aren't they buying one and finding out?
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06:44 PM
lou_dias Member
Posts: 5350 From: Warwick, RI Registered: Jun 2000
This is the trans pictured above. I have many others but don't ask. Sore subject to this day with the wife.
Mine broke just like that as well about 2 years ago...I sent Archie pics at the time and he sent me a replacement axle. My 3.4 was making 249 ft*lbs and that was my first clutch dump with the car.
Once that was replaced, my 2nd clutch dump it broke the Held bearing and axle all at once in the same plane. All I did there was swap the outer end. Since then, I shaved the knuckle to make the axle splines go deeper... I have yet to do another clutch dump...
I'm the unluckiest bastard in the Fiero world, I swear as anyone who's followed my thread knows....
Originally posted by lou_dias: Mine broke just like that as well about 2 years ago...I sent Archie pics at the time and he sent me a replacement axle. My 3.4 was making 249 ft*lbs and that was my first clutch dump with the car.
Once that was replaced, my 2nd clutch dump it broke the Held bearing and axle all at once in the same plane. All I did there was swap the outer end. Since then, I shaved the knuckle to make the axle splines go deeper... I have yet to do another clutch dump...
I'm the unluckiest bastard in the Fiero world, I swear as anyone who's followed my thread knows....
Your axle came out and spun around, breaking the trans case open, twice?
And I'm not sure how you could call https://www.fiero.nl/forum/Forum2/HTML/110249.html "not a transmission related failure"? "I just broke a second Getrag." seems pretty clear cut to me. Is there more info and pictures on what actually broke there?
If you look at my Spec clutch problem thread then you will see what happened. I just went back to that thread I started a few month ago since it was related.
Mine broke just like that as well about 2 years ago...I sent Archie pics at the time and he sent me a replacement axle. My 3.4 was making 249 ft*lbs and that was my first clutch dump with the car.
Once that was replaced, my 2nd clutch dump it broke the Held bearing and axle all at once in the same plane. All I did there was swap the outer end. Since then, I shaved the knuckle to make the axle splines go deeper... I have yet to do another clutch dump...
I'm the unluckiest bastard in the Fiero world, I swear as anyone who's followed my thread knows....
Man--I hope that axle issue is corrected by now and not still being installed in others high HP V8 swaps........Looks like the axles are not the correct length and are to close to the outer side of the tuplis causing the issues......
Originally posted by MstangsBware: Man--I hope that axle issue is corrected by now and not still being installed in others high HP V8 swaps........Looks like the axles are not the correct length and are to close to the outer side of the tuplis causing the issues......
Is that an OE tulip designed specifically for the F40 or a substitute from another vehicle? An important note to mention is that the F40 to my knowledge in all OE settings comes behind a dual mass flywheel which except where stated otherwise and according to a rep from the flywheel manufacturer of the G6 flywheel is torque limited. I may have exceeded its capacity on one test run but had no way of determining if it was the flywheel or the Kevlar clutch disc which appeared to be fine on a resent disassembly.
As a result of this revelation I believe I'm going to have my clutch disc modified for a full spring hub as I'm using the G6 hub and I have staked the top half of the flywheel to the bottom so except for the small springs in the stock G6 hub it is near static.
I don't believe the Getrag or Muncie would fair any better under the same circumstances. I didn't read the entire thread but I suspect a solid clutch setup and excellent traction, although you don't have full power between shifts letting the clutch snap out at 6200 rpm in 4th gear with suspected high 300 to mid 400 lb/ft of torque or more has to transmit a tremendous amount of shock to a transmission if my suspicion is correct especially since you probably have the equivalent of the full torque since the engine rpm is much higher than the associated speed at the time of the shift calls for. Without the full detail regarding how the car was being driven it's hard to know for sure.
Hope it's a case of extreme otherwise it defeats the purpose of my forged motor build.
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07:05 AM
Oreif Member
Posts: 16460 From: Schaumburg, IL Registered: Jan 2000
LMAO You comment quite a bit on the v8 guys Ummmmm don't you have an LS4 swap your doing? Doesn't that make you one of those V8 guys?
Any tranny can blow at any time regardless of torque being put down, but if put down right you can get
longer life out of any tranny. That being said I would definately like to see Troy Boy perform that monster V8 he has. I bet it would perform well and hold up just fine>
LMAO You comment quite a bit on the v8 guys Ummmmm don't you have an LS4 swap your doing? Doesn't that make you one of those V8 guys?
>[QUOTE]
Yeah I am slowly working on a LS4 so one day I will be one of those V-8s guys....But I wil drive the car like it has a V-8 in it and not like I am trying to win a slow race.......Not to mention I am not doing a V-8 swap for the rumble or to say I have a V-8 in a Fiero...
[This message has been edited by MstangsBware (edited 07-28-2010).]
Originally posted by MstangsBware: Yeah I am slowly working on a LS4 so one day I will be one of those V-8s guys....But I wil drive the car like it has a V-8 in it and not like I am trying to win a slow race.......Not to mention I am not doing a V-8 swap for the rumble or to say I have a V-8 in a Fiero...
Why'd you decide to do an LS4 then? If you're just going to beat the piss out of it, does it really matter much what engine it is?
Why'd you decide to do an LS4 then? If you're just going to beat the piss out of it, does it really matter much what engine it is?
I didn't say anything about beating the piss out of it...those are words you are making up....I chose the LS4 because it was a V-8 that came with a trans that can handle the HP/TQ is puts down. I didn't want to be like most others that have to watch how they drive their cars or not be able to drive it to its fullest. That is why I chose the LS4......
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01:44 PM
fieroguru Member
Posts: 12335 From: Champaign, IL Registered: Aug 2003
Originally posted by MstangsBware: II chose the LS4 because it was a V-8 that came with a trans that can handle the HP/TQ is puts down. I didn't want to be like most others that have to watch how they drive their cars or not be able to drive it to its fullest. That is why I chose the LS4......
Its funny you say that... the guys with the LS4 subsection on LS1 Tech are always talking about tranny issues (I think there have been 3 tranny issue threads this week). The guys that own them, upgrade them and drive them consider the 4t65e-HD the weak link.
The 4T65E trans has always been the weak link, even in stock engine cars. It doesn't matter if its the 3800, the LS4, or the Volvo variant (they hate them just as much).
Its funny you say that... the guys with the LS4 subsection on LS1 Tech are always talking about tranny issues (I think there have been 3 tranny issue threads this week). The guys that own them, upgrade them and drive them consider the 4t65e-HD the weak link.
I agree they are the weak leak in the heavy donor cars they come out of.......
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05:59 PM
rcp builders Member
Posts: 736 From: north port, Fl. Registered: Apr 2007
the 5 speed from the 2008 saab has awesome gearing, except for the final drive... i wonder if there is an alternate final drive that can be installed? maybe the final from an F40 can be modified to fit? anyways....the search for a 1st gear/final drive combo BETTER than a hybrid 4 speed continues...
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11:40 PM
Jul 29th, 2010
rcp builders Member
Posts: 736 From: north port, Fl. Registered: Apr 2007
I have yet to injure a 4T65e, nor have I really seen any of my friends hurt one in their heavy cars. I think these automatic trans problems people have are more fabricated than anything.
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12:13 AM
Raydar Member
Posts: 40963 From: Carrollton GA. Out in the... country. Registered: Oct 1999
not to be a jerk but i had a 04' gtp comp g it was bought by my mom brand new with 200 miles on it. and when i bought it from my parents the trans was slipping at 105k. was not beat on a day in its life all maintaince was done on the car. almost all highway miles when i bought. when i drove it i drove it hard i mean hard till about 150k when i sold it. what im trying to say is they can take a beating and keep going for a little bit in stock form. and than others are just junk to begin with. when i sold that i bought a 06' gxp with 78k and had it a week trans went. i did not beat on it drive it very nice. i want to take care of it i got out of the beat on my car praying it didnt break. and when i say the trans went out i mean it literally stopped moving in drive with the service mang. in the car with me he didnt believe tranny was bad. what im trying to say is the 4t65e is not bullet proof it is a major weak point of the car with the 3800sc or LS4. what people are doing is sending it to TEP to be built.
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12:42 AM
fieroguru Member
Posts: 12335 From: Champaign, IL Registered: Aug 2003
Originally posted by darkhorizon: It was clear that shifting into 4th, and letting the clutch out (turbo car, so you wont be shifting on top of full power) broke it. Combination of shockload and just too much power hitting the gears. There is little to nothing that is going to save your gears if they are just that weak.
Second gear failed while shifting into fourth. The only way that can happen is if second gear is engaged, as power only flows through one set of gears at a time (other than the transfer gears at the end of the mainshaft and the countershaft).
My take: this failure was because both second and fourth gears were engaged at the same time. The driver was shifting very quickly and was pulling hard on the shifter to do so. As he pulled through the center of the gate, he pulled the lever towards himself and accidentally shifted back into second. I checked my F40 and it takes very little misalignment of the shifter cables to allow that to happen. The shifter mechanism on the transmission has a ramp that directs the shifter mechanism into second rather than allowing it to stop between the 1-2 and 3-4 gates.
So how did he get two gears? The mechanism itself has a lock-out preventing two gears from being selected so it shouldn't happen and can't happen normally. This has been puzzling me for a while but I think I have the answer. By shifting very quickly, the 3-4 synchro is traveling quite quickly and overshoots to engage fourth as second gear is inadvertently selected because of the misaligned shifter cable, allowing both fourth and second to engage. When this happens, the cluster with the smallest (and weakest) gear breaks, which is second gear.
It's pretty rare to break gears in the upper range, it's almost always first or second because of the shock loading when launching or shifting. Being the smallest gears, they are the weakest and have the most torque multiplication through them.
I have a vested interest in finding the root cause as I will be using an F40 transmission in an upcoming project that hopefully will top the 500 WHP mark. I was initially quite concerned about the two failures but I'll be going ahead now and will make sure the shifter mechanism works perfectly before performing any full-on runs through the gears.
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08:58 PM
Fierobsessed Member
Posts: 4782 From: Las Vegas, NV Registered: Dec 2001
Nah, it cannot happen while the transmission is in motion. I vote that he miss shifted into second, weather intentionally or not.
Think about this, for the most part the gears are all in motion when the transmission is spinning. All of the engaging collars (I don't know what the proper names of these parts are) are arrow tipped, as are the gears that they slide into to engage. They also are always spinning at a different speed, until the clutch is disengaged and the synchronizer speed matches these to allow the collar to slide on effortlessly engaging that gear to the output shaft. If a transmission is in gear, no other synchro has the mechanical ability to match its gears speed to the shaft, The engaging collar won't be able to get past that syncro to engage the gear, and even if it did, it would be met with arrow tipped engagement teeth that it will just buzz and grind against, continued force into these parts will just grind them into dust. It will never find its magic spot and slide right in because the parts are going different speeds. The only exception to this, is when the transmission is motionless, and the interlock mechanism has been broken or removed.
So, the pictured evidence strongly implies that he shifted into second gear after topping out third blowing the teeth right off the gears. I don't care how strong the driver shifts, getting the shifter to break the interlocks, through the synchronizer, and somehow, managing to get the engagement collar past the arrow tipped teeth and actually making a meaningful engagement, WHILE AT MAX RPMs is pretty much impossible.
And... It gets better. Looking carefully at the picture of the transmission. Something is missing! It looks like the inertial shifter weight has been cut off. When they built the shifter gate springs, the weight of this piece is a MAJOR factor in the selection of the springs. Lower gears and reverse are when the weight is high up, 5th and 6th are when the weight is low. This weight HELPS you to shift in the correct direction. Removing it puts a major bias towards lower gears into the shift gates, strongly encouraging mis-shifting into lower gears. This weight is also especially helpful when going from 1st to 2nd, and 3rd to 4th, since it is one fluid movement with that inertia weight behind it. I have a feeling both transmissions that he broke are missing this weight.
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11:58 PM
Nov 16th, 2010
mender Member
Posts: 299 From: Didsbury, Alberta, Canada Registered: Nov 2010
I'll have to disagree with you regarding the synchromesh mechanisms (the proper name for the engaging collars). Contrary to what you're saying, it is quite possible and even not that hard to shift quickly enough to mesh the synchro despite a large difference in shaft speeds. Back in the bad old days, this quirk was exploited by shifting without the clutch and without lifting off the throttle. Yes, powershifting. The faster the pull on the shifter, the more likely it was that the shift would be successful. Hesitation was disastrous!
I mistakenly pulled one vehicle into first without depressing the clutch once and to my surprise it clicked in cleanly and the vehicle lurched forward with a little spitting of gravel. A mini-demonstration but quite convincing.
Anyways, we run crashboxes in the race cars I maintain, which use much the same principle but with specially designed dog rings with more room for the non-clutched shifts. Same thing here; a quick pull is less likely to miss.
Your theory of only engaging second would have resulted in the engine over-revving as the clutch was released and the driver got back on the gas with second only engaged. There was no mention of a sudden flare in rpm, which I'm sure would have been mentioned and considered as a missed shift, which they specifically dismissed. That tells me that the transmission was in fourth AND second, with second stripping immediately and leaving the expected fourth gear engagement. They also couldn't shift into fifth or sixth afterward, implying to me that another gear (fourth) was still engaged during the attempt. In that case, your comments about engaging two gears simultaneously would apply as I expect they were being somewhat cautious in their attempts.
Also, since the gear loading would have been much less than that experienced with the engine pulling properly, there is little reason to believe that a simple missed shift into second would explain the carnage.
In summary, it is quite possible to engage two gears at the same time and shifters have interlocks specifically to prevent that. However, if the shifter is not adjusted correctly, the unthinkable can happen with the resulting destruction of the weaker gear set as I mentioned. Not as uncommon as one would hope.
I'll stay with my explanation for now.
[This message has been edited by mender (edited 11-18-2010).]
