3.1 to a 4 cylinder Fiero swap

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   Hey guys I have a couple really quick questions I own two cars one is 

an 89 Oldsmobile Cutlass Supreme. It has a 3.1 liter v6 engine. I did 

some research online and noticed that the v6 Fiero and the v6 

cutlass supreme both use a Getrag standard transmission. 

 Will the transaxle match up to the transmission?

 Or will I have to buy a Getrag standard transmission?

 The old mobile have an automatic transmission and I would prefer 

to keep it instead of buying the get rag standard.

 Last question what kind of hoops am I going to have to hop through 

in order to take the front wheel drive engine and transmission and 

put it in my Fiero?

 Thank you for your time

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kole83 Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 07 July 2013 Location: United States Status: Offline Points: 5	Post Options Post Reply Quote kole83 Report Post Quote Reply Topic: 3.1 to a 4 cylinder Fiero swap Posted: 09 July 2013 at 12:38am
	Hey guys I have a couple really quick questions I own two cars one is an 89 Oldsmobile Cutlass Supreme. It has a 3.1 liter v6 engine. I did some research online and noticed that the v6 Fiero and the v6 cutlass supreme both use a Getrag standard transmission. Will the transaxle match up to the transmission? Or will I have to buy a Getrag standard transmission? The old mobile have an automatic transmission and I would prefer to keep it instead of buying the get rag standard. Last question what kind of hoops am I going to have to hop through in order to take the front wheel drive engine and transmission and put it in my Fiero? Thank you for your time

Erwin Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 13 February 2007 Location: Canada Status: Offline Points: 38	Post Options Post Reply Quote Erwin Report Post Quote Reply Posted: 09 July 2013 at 12:45pm
	Both 2.8 and 3.1 have the same bell housing pattern. You will also need to decide if you are running the fiero intake and computer, or the cutlass intake and computer. Other issues are converting the 3.1 from flexplate and torque converter to Pressure plate. Any swap you do, consider if the benefit is sufficient for the effort. Your 3.1 cutlass motor LH0 is rated at 140 hp as opposed to the stock 2.8 fiero motor making a rated 140 HP So no real benefit in power over putting in a stock Fiero V6... That said - if you like tinkering it is perfectly possible to do the swap. The Fiero system is essentially a GM front wheel drive system and suspension put into the back of a car.

kole83 Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 07 July 2013 Location: United States Status: Offline Points: 5	Post Options Post Reply Quote kole83 Report Post Quote Reply Posted: 09 July 2013 at 1:00pm
	Ha I never noticed that. Thanks man! Now here is my next problem. I have a 4cyl frame. Am I going to have some problems with the transaxle? Matching up the tranny to frame?

kole83 Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 07 July 2013 Location: United States Status: Offline Points: 5	Post Options Post Reply Quote kole83 Report Post Quote Reply Posted: 09 July 2013 at 5:58pm
	Also I'm keeping the transmition from the olds to use in the fiero. Do I still need to worry about the pressure plates?

bcampbell Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 14 November 2011 Location: Canada Status: Offline Points: 160	Post Options Post Reply Quote bcampbell Report Post Quote Reply Posted: 11 July 2013 at 3:42am
	If you're swapping engine/transmission together then there should be no reason to worry about the pressure plate. Rodney Dickman sells some pieces to make the 5- speed FWD transaxles work in the Fiero easily as well. As for power, the LH0 actually makes 15 more ft-lbs of torque than the Fiero 2.8. Wiring would be pretty easy; you can re-pin the Fiero ECM connectors for the Cutlass ECM, and you may have to change out some pigtails as well, but other than that it's pretty straightforward. The DIS ignition used on the LH0 is significantly more reliable than the 2.8 iron head stuff and there's no need to ever mess with a timing light either. You can also keep the FWD accessory setup with an idler pulley where the power steering is and you should never deal with belt squeal again either. Since you're not starting with a 2.8 already, IMO you would be going backwards to try putting 2.8 stuff on the 3.1. Not to mention if you didn't also swap in 3.1 iron head pistons you would end up with something like 6/7:1 compression... The only downside to the aluminum heads is you have to re-work or relocate the dog-bone mount.
	'86 2m6 F23 5-speed, LSD, 3.5L LX9 '89 Firebird 3500T, T56

kole83 Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 07 July 2013 Location: United States Status: Offline Points: 5	Post Options Post Reply Quote kole83 Report Post Quote Reply Posted: 11 July 2013 at 10:27am
	Thx cambell. Now I have one last question. Is my stock 4cyl fiero rear axle going to be able to handle the extra torqe? Or am I going to have to be purchasing a v6 rear axle and place that in?

bcampbell Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 14 November 2011 Location: Canada Status: Offline Points: 160	Post Options Post Reply Quote bcampbell Report Post Quote Reply Posted: 11 July 2013 at 12:19pm
	Do you mean transmission? IIRC the only stock transmissions that can be broken with stock V6 power are the 84 4-speed and the Isuzu 4-cylinder 5-speed. Depending on how you drive though you can make any transmission last.
	'86 2m6 F23 5-speed, LSD, 3.5L LX9 '89 Firebird 3500T, T56

kole83 Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 07 July 2013 Location: United States Status: Offline Points: 5	Post Options Post Reply Quote kole83 Report Post Quote Reply Posted: 11 July 2013 at 12:21pm
	Ok sweet man. Ill let ya know how it goes.

Dr.Fiero Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Post God Joined: 12 February 2007 Location: Canada Status: Offline Points: 1726	Post Options Post Reply Quote Dr.Fiero Report Post Quote Reply Posted: 11 July 2013 at 12:21pm
	All Fiero transaxles are the same (power handling wise), as are all the CV shafts the same. (edit: but as stated - you CAN break anything! There are guys running V8's attached to Isuzu's for years without issue)

Capt Fiero Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Founding Member Joined: 12 February 2007 Location: Canada Status: Offline Points: 4039	Post Options Post Reply Quote Capt Fiero Report Post Quote Reply Posted: 12 July 2013 at 10:49am
	Uhm, John what you been smoking? Or are you just exhausted from all the jobs you are working on. Strength of Fiero Trans from Weakest to Strongest. Isuzu 5spd 2nd Gear Disintegrates 84 4spd 3.32 Case Breaks 84 4spd 4.10 Case will break eventually 86-88 Getrag 5spd Usually internal failures like shafts and such. 85-86 3.65 4spd Only failures have been age related like snychros or shafts. Now I have ran the Isuzu on my V8 Fiero with Nitrous. I would blow one about every 6 months. The only V6 4spd trans I have ever blown was a bad internal shaft. I have never been able to crack a case or strip a gear on a V6 4spd trans. Even when going redline in reverse then quickly shifting to 1st gear and popping the clutch. I have installed the Getrag 5spd in my V8 now just for better strength over the Isuzu. Gearing is not as good as the Isuzu, but its much more reliable. The Auto Trans is also very strong, but really crappy gearing. The reason GM did not install the Isuzu on the V6 is even they knew it would not handle the abuse in the long term. Now as Erwin said, all Fiero Manual CV's are the same and you will never break one behind a V6 unless its Supercharged and even then it has to be seriously modified. I believe they will fail around 400hp and 500lbs of torque.
	Capt Fiero 88 Fiero GT 5spd V6 Eight Fifty Seven GT V8 5spd.