what dohc ECM is best to use for a future turboed engine? guessing obd1 for ease of programming
wouldn't know Kohburn, i'm using a Haltech E6X
I don't want to leave the tuning of my engine to someone burning a chip. I've got too much money in my swap to have to repair it, I've done this before and real time tuning is the only way to go.
I don't want to leave the tuning of my engine to someone burning a chip. I've got too much money in my swap to have to repair it, I've done this before and real time tuning is the only way to go.
thats what i figured.. have you dynoed or tracked it yet?
i second dave gunsuls thoughts, it would be cool to ride in it for sure. How much HP should that thing be putting out and when is it gonna be broken in?
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03:45 PM
Oct 14th, 2004
Fierobsessed Member
Posts: 4782 From: Las Vegas, NV Registered: Dec 2001
I just thaught you might be interested in seeing some more differences. 94-95 heads vs 96-97 heads. Notice the 96-97 head has a clover combustion chamber while the 94-95 has a pent roof chamber roughly the same as a Quad 4, but the valve angle is not quite as aggressive as the quad. 96 pistons have a 2.2" raised section, about .040" high in the center of the piston. The 94-95 are flat tops with valve reliefs.
Updates on my particular project: Iv'e been collecting parts to fix my tig welder so I can have a co-worker weld my intake manifold togather. We had rented one for a job and he layed a couple welds to hold the manifold togather. looking good so far. As you can see, I absolutly needed to have a 96 motor to make this manifold work. The fact that the ports are in an exact line was what made this possible. And this is what the assembly looks like togather. There are other parts that will hold the blower onto the engine and keep it from moving (and leaking). Thats later on down the road. I just need to cough up the $'s for forged pistons and the steel 4340 327 SBC rods I plan on using. And yes, the blower will stick up into my rear view significantly.
I'm not 100% sure, but what I think happened throughout the development of the 3.4 DOHC goes as follows. The test mule 3.4 DOHC's probably were excessivly powerful and had to be detuned for the general public. The 3.4 DOHC and the 2.3 Quad 4 are very closley nit in there construction. They have the same bore and stroke, the valvetrain is nearly interchangeable! the valves and the lifters are VERY close in size but not quite the same. If they would have made the 3.4 DOHC with the cams spec'd the same as the Quad 4 HO, you would have a near 250+ horsepower engine. But they never went that route. I think when the compression ratio went up in 96, the ports are all much better and free flowing, that GM wasn't interested in making more power, because seriously, they only got 5 more horses? Im sorry but thats Pure plain and simple. The cams were obviously detuned. An untrained eye can see that the duration on a 95 cam is more then a 96. The lobes are fatter. Oh well. The engine has all the right stuff to be a great boosted motor, with exception to the compression ratio.
For the computer, I am still toting the development of a code based on the 89-90 Turbo Grand Prix code (AUAF $8F) but modified for the unique flow characteristics of the 3.4 DOHC. But to make the whole project simpler. Im using a 1227730 computer instead of a 1227727 from the grand prix. Its electrically identical, but a stock 2.8 harness would only have to be modified for a couple of sensors some location movments and then alittle repinning in of a third ECM connector. It doesn't get much easier then this! The 1227727 would practically require the entire harness to be custom made. Ive been collecting the required parts to re-program the ECM, but I would be learning how its done as I go. I'm just waiting on my ALDL cable to arrive with the software so I can get started playing with my ECM. (witch is now on a 3.4 PR)
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12:05 AM
fieromadman Member
Posts: 2217 From: Oconomowoc WI, USA Registered: Jan 2003
I made a similar observation in Koburns thread. It's crazy that they only would come up with 5 HP when the later engines had higher compression and better heads. I knew they must have done something to detune it but I wasn't sure what.
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01:02 AM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
what dohc ECM is best to use for a future turboed engine? guessing obd1 for ease of programming
The 89-90 Turbo 3.1 Grand Prix computer can be reprogrammed to work with the 3.4 DOHC engine. However, it is only batch fire like the 91-93 DOHC ECM, but it does not have the capability to control a 4T60-E trans like the 91-93 ECM. The TGP computers are far more common than the 91-93 DOHC computers are though and do share the same underhood design.
This is the swap that I would love to do, but I don't have enough experience. I have no problems taking engines out and putting them in, but swapping in a completely different engine is another story. Plus the wiring scares me. Getting everything to function properly would be my main problem. Darth, how much do you charge to install one of these? Also, I may have missed this somewhere in the thread, but which cars have these engines?
------------------ 86 SE 4 spd - 86 GT auto - 86 SE auto oh yeah, and the 85 coupe parts car
I made a similar observation in Koburns thread. It's crazy that they only would come up with 5 HP when the later engines had higher compression and better heads. I knew they must have done something to detune it but I wasn't sure what.
yeah when i was looking at the specs on 60degreev6 i noticed the cam timing on intake was about 5* advanced and the exhaust was about 3* retarded.. the cams should be swapable right? 95 cams on a 96 motor with the 10-13* exhaust cam retard.. I bet the later motor would just scream...
Originally posted by Fierobsessed: The cams were obviously detuned. An untrained eye can see that the duration on a 95 cam is more then a 96. The lobes are fatter. Oh well. The engine has all the right stuff to be a great boosted motor, with exception to the compression ratio.
For the computer, I am still toting the development of a code based on the 89-90 Turbo Grand Prix code (AUAF $8F) but modified for the unique flow characteristics of the 3.4 DOHC. But to make the whole project simpler. Im using a 1227730 computer instead of a 1227727 from the grand prix. Its electrically identical, but a stock 2.8 harness would only have to be modified for a couple of sensors some location movments and then alittle repinning in of a third ECM connector. It doesn't get much easier then this! The 1227727 would practically require the entire harness to be custom made. Ive been collecting the required parts to re-program the ECM, but I would be learning how its done as I go. I'm just waiting on my ALDL cable to arrive with the software so I can get started playing with my ECM. (witch is now on a 3.4 PR)
well the duration could still be the same but with reduced acceleration on the valves so they aren't wide open for as high a % of that duration.. a less agressive cam for reduced wear?
this 1227730 ecm.. what is it out of? its currently running your 3.4 pushrod?
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07:37 AM
crzyone Member
Posts: 3571 From: Alberta, Canada Registered: Dec 2000
The 16194396's are actually much more common then you might think. They came in Every 3.1 and 3.4 Powered W body from 91-93. The nice part about that one is that the ECM pinout is almost identicle to the 1227727's. The only difference is the transmission control and the EGR uses different pins (as well is a different type). In my experience, the 3.4 DOHC really likes manual transmissions since it has such a broad power band (witch has alot to do with it being detuned) so in most applications, the 16194396 is probably not necessary. I prefer to use the 1227730 computer over the 1227727 for many reasons. First, its electronically Identical to the 1227727, will run all the same programs, do all the same functions, and it fits in a stock 87-88 4 cyl computer holder. The 87 and 88 Fiero V6 harness plugs already fit into two of the 3 computer sockets. Just movinig wires to the third harness connector is about 70% of the wiring for the whole swap. Change out the V6 distributor for a DIS (uses the same number of wires and most of the colors are the same too!) then add extra wire for the knock sensor, the coolant fan is to be wired to the computer instead of a sensor, add wires for the new EGR, then lengthen or shorten other wires as needed (most notably the injector harness) Not too bad if you ask me.
The drawbacks to this system, you cannot run a 4T60-E (but you could beef up a 4T60) you need to change or disable the egr depending on what year DOHC. You will no longer have SFI capability, and there is no program available yet that will even run the engine good enough to drive much. But that can be remedied as soon as its been done once.
The 1227730 came out of MANY cars. I can easily get 10 of them for 250$ dime a dozen. 87-93 vehicles equipt with either a 2.8 or 3.1 Chevy Beretta Chevy Corsica Chevy Cavalier Chevy Camaro Chevy Celebrity Pontiac Firebird (even the V8's in 91') Pontiac 6000 Pontiac Sunbird Pontiac Tempest Oldsmobile Ciera Oldsmobile Firenza Buick Century
[This message has been edited by Fierobsessed (edited 10-14-2004).]
Well I'm thinking around 3K so that the rings set in good, I'd like to switch to Mobil 1 once that is done. You get different answers if you ask around bout the time frame for this.. I don't know what kinda break in that GM does on it's cars that come standard with Mobil 1, are they already broke in or what.. So I think I'm going to call Mobil and see what they say and maybe GM too.
you guys know that for the first 80-100 miles a car is broken in, your supposed to ride it hard with regular engine oil so the rings seal, right? LOTS of fast 0-80 mph runs on the highway...
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01:56 AM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
you guys know that for the first 80-100 miles a car is broken in, your supposed to ride it hard with regular engine oil so the rings seal, right? LOTS of fast 0-80 mph runs on the highway...
You should run the car through its paces and different rpms throughout its break in, dont baby it, just dont over do it..I have built many motors and have never had a problem doing this. You shouldnt NOS it or put much if any boost at first til after the break in period
[This message has been edited by Erik (edited 10-15-2004).]
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02:34 AM
Will Member
Posts: 14249 From: Where you least expect me Registered: Jun 2000
Boost seats rings fast. The best break in for a new engine is to run the pee out of it.
Bearings don't break in. The only break in required is by the rings. When you first start the engine, drive it gently for a few minutes to let the rings seat to the ring grooves, then let it idle for a few more minutes to get all the oil through the oil filter. Change the oil filter, and if you want the rest of the oil as well. Inspect magnetic drain plug if you have one.
Once you've done that, go out and drive it like you stole it. Allen Cline at GM recommended that I put my car in 2nd or 3rd gear and go from 4K to redline, engine braking back down to 4K, 20 or more times.
------------------ Turn the key and feel the engine shake the whole car with its lope; Plant the gas pedal and feel in your chest neither a shriek nor a wail but a bellowing roar; Lift and be pushed into the harness by compression braking that only comes from the biggest cylinders while listening to music of pops and gurgles. Know that you are driving an American V8. There are finer engines made, but none of them are this cool.
Luck, Fate and Destiny are words used by those who lack the courage to define their own future
Sorry I found this thread so late, Dave the 3.4 DOHC can be both fun and fast. Darth was recently able to aquire a 1987 with a 3.4DOHC he put in the car before he went to college (yeah it's a flashback of his work) Anyway we went to the track this weekend and since he's been working on other people's swaps didn't have much time to do anything to this car but clean up a little wiring. It managed to run a 14.1 in the quarter and break a motor mount at the same time, so much for power shifting! Heck, it even ran faster than my 3800 (automatic). I'll be honest though, I'm getting a little old and the exhaust is a little overbearing for a long trip. I guess it just depends on what you want, but there is plenty of power if you want it in just about any swap. A lot of it depends on your tolerance, ability, and pocketbook. The beauty of swaps and the fiero community in general is that each car can be tailored to the owners idea of a beautiful car. Good luck and happy deciding what to do!
Boost seats rings fast. The best break in for a new engine is to run the pee out of it.
Bearings don't break in. The only break in required is by the rings. When you first start the engine, drive it gently for a few minutes to let the rings seat to the ring grooves, then let it idle for a few more minutes to get all the oil through the oil filter. Change the oil filter, and if you want the rest of the oil as well. Inspect magnetic drain plug if you have one.
Once you've done that, go out and drive it like you stole it. Allen Cline at GM recommended that I put my car in 2nd or 3rd gear and go from 4K to redline, engine braking back down to 4K, 20 or more times.
I knew a guy who used to break in his motors by running the crap out of them from the get go ..His reasoning was if its going to break its going to break right away. He would rev the bejebus out of them. He was right, most of the time but he did have his fair share of early failures ..My motors have never failed, except from high mileage and many times down the track, knock on wood er a aluminum Anyway, I have seen a few motors that never seated, all turbo, that were run in like they were stolen. Dont baby it like everyrone seems to want to do with a new motor but dont rag on it. Run it through its rpms, let it go through some heat cycles. Also, check the oil and filter after the initial run in and change
[This message has been edited by Erik (edited 10-15-2004).]
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03:11 PM
PFF
System Bot
Will Member
Posts: 14249 From: Where you least expect me Registered: Jun 2000
------------------ Turn the key and feel the engine shake the whole car with its lope; Plant the gas pedal and feel in your chest neither a shriek nor a wail but a bellowing roar; Lift and be pushed into the harness by compression braking that only comes from the biggest cylinders while listening to music of pops and gurgles. Know that you are driving an American V8. There are finer engines made, but none of them are this cool.
Luck, Fate and Destiny are words used by those who lack the courage to define their own future
For $250 Erik can make you a harness. $50 and Darth can reprogram your prom, eassssyyyyy!! The motor its self is a no brainer to install.
Really? I may have to give this one a try then.
Which cars are these engines in? I'm going to have to start hunting around in the yards. The only one I know of is the Z34 Monte Carlo because I just saw one a couple days ago that was being worked on.
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12:05 AM
fieromadman Member
Posts: 2217 From: Oconomowoc WI, USA Registered: Jan 2003
lumina z34's GTP's from 91-97(?) some lumina euro's monte carlo z34's olds cutlass's from the 91-97 vintage maybe a few more different cars but i think thats about it...
------------------ REMEMBER: If you cant win the race you loose the argument!! 3.4 DOHC Motor Swap-14.7 in the 1/4 mile with no hook-up, crumby exhaust and automatic chip. Better exhaust, chip, cam retarding, and driver to come... I'm feeling lucky! www.geocities.com/j_depies
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01:00 AM
blackrams Member
Posts: 32121 From: Covington, TN, USA Registered: Feb 2003
I simply love how I can read a post in this forum, that deals directly with the 3.4 TDC vs the pushrod 6s, and not have to read one post involving flaming of any sort. God it is so nice, you couldn't imagine.
Let me say I will be going with the 3.4 TDC. For a couple reasons. I have dealt with the motor a lot, and I'm in love. Even in the heavy Luminas, it still has great power and is smooth. I also have a couple of them, and that helps too I guess. Hopefully I will be in the 13s directly after the swap, that would make me really happy.
From reading, I need to kiss all my fears out of my head and just do it already.
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08:19 PM
AaronZ34 Member
Posts: 2322 From: Colorado Springs, CO Registered: Oct 2004
lumina z34's GTP's from 91-97(?) some lumina euro's monte carlo z34's olds cutlass's from the 91-97 vintage maybe a few more different cars but i think thats about it...
1991-1994 Lumina Z34 and select Euro 1995-1997 Monte Carlo Z34 1991-1996 GTP and select SE or STE 1991-1997 Cutlass
The 5-speeds were only available in 1991-1993, and had 210hp/215tq thx to higher compression than the autos. 9.5 vs 9.25. However in 1996-97, they went to a slightly different head, and with 9.7 c/r got 215hp/210 tq. The 91-95 autos were 200hp/200tq. A little about the later years. The heads were better, but believe it or not they were not that much better. Yes more than 5hp, the cam specs did change. Also their intake's runner lengths were decreased, which for only shortening it 2" did a lot. It moved the enitre power range. In 1991-95, the motor made max power at 5500rpm. Move to 96-97, and your making max power at 6400. Good for sticks, bad for the autos. Since all were autos, they were a bit slower down the 1320 than the first gens.
I'll be using a 1992 5-speed motor, just becuz I have one. And heads aren't an issue as they are getting fully P&P with SI valves/springs, and custom lifters. I will someday have some regrind the cams, but for now I will just be playing around with retarding them/advancing them to match the intkae I'll be using.
Hope this helps!
------------------ 1992 Lumina Z34 5-speed 14.78 @ 92.68 1992 Lumina Z34 5-speed Offered to donated its organs to Fiero
[This message has been edited by AaronZ34 (edited 10-18-2004).]
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08:23 PM
Rugby13 Member
Posts: 103 From: Stroudsburg,Pa Registered: Jan 2004
Hey sorry to get off topics but I didn't want to start a whole new thread for this...I searched but couldn't find anything. How much does the average 3.4DOHC swap cost? I want to put it in an 86 GT auto but I want to put a five speed in as well......anyone know a ballpark price for this swap? I might be able to get a decent deal b/c my friend owns a junkyard.
Thanks,
-chris
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09:20 PM
skidpro1 Member
Posts: 438 From: portland,or usa Registered: Sep 2004
Sounds like a great swap ! Only thing I would question is the weight of the motor, at 492.5 lbs. you would have to go to a big block to weigh more. Has anyone that has done this swap found this to be a problem as far as handling goes?
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09:40 PM
Oct 19th, 2004
hoola47 Member
Posts: 526 From: London, Ontario, Canada Registered: Feb 2003
Sounds like a great swap ! Only thing I would question is the weight of the motor, at 492.5 lbs. you would have to go to a big block to weigh more. Has anyone that has done this swap found this to be a problem as far as handling goes?
I didn't believe you, did a search, and man what a pig of a motor. I love the rev's, the 4 cams, the rev's, oh yeah I said that, but that is HUGE. A lot of people say don't get a V8 because of the handling issue, this engine I'd think would weigh more than a v8 with aluminum heads, its heavier than a 3800 with a supercharger! Another 100+ pounds, ouch.
------------------ 1986 Pontiac Fiero GT Auto, soon to be 5 spd Getrag from 88 z24, Best 1/4 = 16.1 at 83mph, mods, wires, CRX intake, and power pulley. Planning Turbo 2.8 swap for a little more umph!!!!
Bought for 2500$ Canadian.
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12:20 AM
PFF
System Bot
crzyone Member
Posts: 3571 From: Alberta, Canada Registered: Dec 2000
That weight figure is hard to believe, its a basic 60* block with aluminum dohc heads. The block its self is fairly light. As light as a 2.8s. Anyone who has had the heads off know how much heavier they are than the cast pushrods? Or if they are?
Find it VERY hard to believe that the tdc's weigh more than a full cast iron 3800 with the supercharger.
If it matters, the 3.4 didn't feel much different on the engine lift than the 2.8??
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01:15 AM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
That weight figure is hard to believe, its a basic 60* block with aluminum dohc heads. The block its self is fairly light. As light as a 2.8s. Anyone who has had the heads off know how much heavier they are than the cast pushrods? Or if they are?
Find it VERY hard to believe that the tdc's weigh more than a full cast iron 3800 with the supercharger.
If it matters, the 3.4 didn't feel much different on the engine lift than the 2.8??
The DOHC is about 50 lbs heavier a stock 2.8. Even though it has aluminum heads the weight saved over iron OHV heads on astock 2.8 is countered by the DOHCs 4 cams and cogs and valvetrain. I dont notice any difference in handling between a stock 2.8 and the DOHC. moving the battery up front really helps and counters the little added weight in the rear from the DOHC swap.
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01:23 AM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
Hey sorry to get off topics but I didn't want to start a whole new thread for this...I searched but couldn't find anything. How much does the average 3.4DOHC swap cost? I want to put it in an 86 GT auto but I want to put a five speed in as well......anyone know a ballpark price for this swap? I might be able to get a decent deal b/c my friend owns a junkyard.
Thanks,
-chris
A ballpark cost for the swap provided you do your own work a bare minimun would be about 500.00 excluding the motor and trans and car. I did mine for about that by doing all my own work.Most of that was spent on a new clutch setup and flywheel. Of course I had the engine and trans already and car also. Total amount including trans, engine and car was about 1400.00. A trans can be had for 200 to 300 an engine on average goes for 500 to 700.
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01:39 AM
skidpro1 Member
Posts: 438 From: portland,or usa Registered: Sep 2004
Go to www.fieroaddiction.com all the motor wieghts are there ,unless they made a mistake it is one heavy motor. I would like to do this swap but I really want to know the truth on the wieght of the motor? Does it wiegh 50 lbs more then the 2.8 or 490+ lbs. which is more then an alum. head SBC.
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11:36 PM
Oct 20th, 2004
hoola47 Member
Posts: 526 From: London, Ontario, Canada Registered: Feb 2003
Go to www.fieroaddiction.com all the motor wieghts are there ,unless they made a mistake it is one heavy motor. I would like to do this swap but I really want to know the truth on the wieght of the motor? Does it wiegh 50 lbs more then the 2.8 or 490+ lbs. which is more then an alum. head SBC.
I have a DOHC short block that weighs 280lbs. I am assuming that the 2.8 shortblock would be similar in weight. I have fully dressed DOHC heads with iron manifolds, cams valves springs and cogs on them that weigh almost 120 together. There is 400 lbs right there without intake and accessories. I cant imagine that the 2.8 iron heads weigh anything less than 40lbs a piece so the 2.8 without intake and accessories would come within 50 lbs of the 3.4 @ about 360 lbs. I would assume that the alternator AC compressor and starter would weigh about the same on the 2.8 as it does on the 3.4. I also had a DOHC shipped to me that was 450 lbs with starter AC and alternator. Yeah, it weighs a bit more than the 2.8 but not really that much.
[This message has been edited by Erik (edited 10-31-2004).]
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12:29 AM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
It just so happens that I recently got a disassembly of the 94-95 3.4 DOHC SFI chip program. I spent about an hour tonight writing out my own definition file for my tuner program. So far I have defined the rev limiter tables, top speed limiter tables, and a few switches, one of which gives me the option of telling the PCM that it is hooked to a MANUAL TRANS! Unforetuneately I don't know if any of this stuff is going to work because I don't have this computer on my 3.4 DOHC so I can't try it. I need to find someone who is willing to do some "beta testing" and try it out for me...
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01:02 AM
skidpro1 Member
Posts: 438 From: portland,or usa Registered: Sep 2004
So it looks like the weight is around the same as the SBC, around 450 lbs. give or take 20. The 2.8 is 370lbs. so the handling would be about the same as a SBC swap. Correct me if I missed something.
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01:27 AM
crzyone Member
Posts: 3571 From: Alberta, Canada Registered: Dec 2000
Pure plain and simple. The cams were obviously detuned. An untrained eye can see that the duration on a 95 cam is more then a 96. The lobes are fatter. Oh well. The engine has all the right stuff to be a great boosted motor, with exception to the compression ratio.
the egr depending on what year DOHC. You will no longer have SFI capability, and there is no program available yet that will even run the engine good enough to drive much. But that can be remedied as soon as its been done once.
