T56 6 Speed

[go-topless]

Has anyone ever put a T56 6 speed behind a 3.8? Is it even possible? What would need to be done for it to work?

Thanks, David

 

[JW87T]

I would think the problem would be boost falling off between shifts, unless you are power shifting. Ball bearing turbo might help this.

I remember seeing Porsche Turbo race cars run once. They had no turbo lag between shifts. Of course, they were running a lot of rpm so lag wasn't a problem.

I think when all is said and done, an automatic is the better choice. Keeps the engine speed up and turbo spooling.

 

["Turbo-T"]

It's been discussed before why a manual trans wouldn't be suitable behind a turbo 3.8 engine.

 

[notacarlo]

Just curious....why would one want to do this?

These things were designed to go in a straight line as fast as possible. I guess if you like the twisties, a manual is more desirable. The suspension may want a say in that decision though.

 

[go-topless]

Just curious....why would one want to do this?

These things were designed to go in a straight line as fast as possible. I guess if you like the twisties, a manual is more desirable. The suspension may want a say in that decision though.

I have a 91 convertible Firebird and a swap from a 89 TTA, I thought a manual would be fun. I'm not looking so much for speed, just something fun to drive and different. What I wanted to know is if the T56 would work with the turbo 3.8, what kind of problems could I expect with everything lining up? Has it ever been done before?

Thanks, David

 

[go-topless]

It's been discussed before why a manual trans wouldn't be suitable behind a turbo 3.8 engine.

Would you happen to have a link?

Thanks, David

 

[notacarlo]

It will work, but it wont just bolt up. You would need an adapter plate, possible motor mount relocation. I'm not sure how well the LC2 would handle the shock of heavy gear change.

You don't know until you try.

I actually had a guy that was going to buy my GN. He told me he was going to put a 5-speed in it. I told him "I thank you for your time" and drove off.

Since you have a spare car with the T56 and a spare LC2, why not? Ultimate sleeper for sure. They will think they know what you have.....but they won't.

 

[DailyDrifter]

A 6 speed would be awsome for a street car. If you do it take pics and get part numbers. Then you can get a Blow-off Valve lol. Seriously it would be cool, I just wish these engines reved out a little more. You would also get great gas milage with a double overdrive.

 

[86GN-862+2]

I have a 91 convertible Firebird and a swap from a 89 TTA, I thought a manual would be fun. I'm not looking so much for speed, just something fun to drive and different. What I wanted to know is if the T56 would work with the turbo 3.8, what kind of problems could I expect with everything lining up? Has it ever been done before?

Thanks, David

I think it would be a fun project. If the 200R4 bolts up to the 3.8L, then the T-56 should bolt up as well, tentatively(you probably need an older bellhousing from a T-5 and the adapter plate to bolt it on to the T-56). You would have to find or have the manual flywheel made(with bolts) to bolt up behind the 3.8 for starters. Then make sure the 3.8's exhaust does not interfere with your bigger manual transmission. You would have to use a different transmission crossmememer most likely. Your driveshaft will most likely have to be shortened or lengthened. If you got the time and $$$ I say go for it! Your starter motor may or may not line up(depending on your flywheel size?) If your car is not manual, then finding all the parts to complete your swap may be a pain. On your manual flywheel, you may be able to use one from a 3.1L/3.4L equipped manual F-body?? g/l!

 

[dr_frankenstein]

It can be done............... I have a manual and I know of a few others here who do as well....... its not tooo hard on the engine but a BOV is helpful.

I can list you all the part numbers that are available at Vato-zone or CSK.

Its not any harder than an automatic... just has more parts.

The T56 is somewhat different though in that the input shaft will need to be shortend about 1/4" to fit the Buick pilot bearing..... and correct bellhousing is needed.

a W/C T5 is alittle easier to install and well 5 speeds aint to bad.

A.j.

 

["Turbo-T"]

Would you happen to have a link?

It's in this board somewhere, you will have to do a search.

I think it's related to how the factory LC2 engine doesn't like to be taken above 5k. Also think of the boost drop off in between gear changes on a manual. If it was a high winding car like a 4 cylinder it probably wouldn't matter.

 

[charlief1]

Doc, post some pics and the part #s please. I have a second 83 I haven't decided what to do with yet.

 

[38turbo]

did the camaros like a 98 camaro with the 3.8 come with a manual trans or just automatic

 

[charlief1]

They had both but the bell housing is the smaller fwd bell housing mount.

 

[charlief1]

Here's the adapter for a late model 5 speed.
eBay Motors: Chevy S10 T5 T-5 Transmission Swap Adapter Spacer Plate (item 280307428534 end time Feb-26-09 20:50:18 PST)

 

[86GN-862+2]

The T56 is somewhat different though in that the input shaft will need to be shortend about 1/4" to fit the Buick pilot bearing..... and correct bellhousing is needed.

a W/C T5 is alittle easier to install and well 5 speeds aint to bad.

A.j.

Could he use a 1/4" aluminum spacer plate instead of cutting the input shaft?
A W/C T5 bellhousing bolted to the T56 will need the adapter to reposition the transmission's shifter upright for the correct angle inside the car, possibly.

Also, the T56 is physically larger than the T5 so the hump may have to be modified as well?

T56 6 Speed Conversion for 82-92 F-bodies

 

[1dollardog]

As far as bell housings go, one from a late 70's or early 80's 3.8 Chevy Monza or Pontiac/Buick equivilant. Also there were a few malibu's and elcamino's that came with the 3.8 with a manual 3 speed trans too. I would think you should be able to use the bell housing and flywheel from one of these due to the engines being the even fire engines. I'm pretty sure that the even fire 3.8 was balanced different from the odd fire 3.8. Where the tranny bolts to the bell housing may need some modification. Stock tranny back then was a 4 or 3 speed saganaw with 4 evenly spaced bolts holding it to the bell. (Someone feel free to correct me if I'm wrong on any of this). I've been gathering a few part for a future project of putting a LC2 in a porsche 914. Mid engine road hugger. I know that has been done with a carbed turbo engine but that is worthy of a whole nother thread.

 

[charlief1]

The H-body bellhousing is cable opp not linkage. The one you want is the 68 to 81 BOPC bellhousing that came in the A body or Firebird. It has provisions for 2 different tranny's. Standard 4 bolt GM AND the ford bolt patern for the top loader. (yes GM really used them) I have one I've been sitting on for 15 years now for a hopeful conversion on one of my favorite vehicles. Or you can bite the bullet and buy a lakewood. I have one of those too.

 

[dr_frankenstein]

OK Ok.... heres a bit of a parts list, i need to dig numbers. All of you are correct!

LOL

So im going to do the combo I have now, and will play with the t56 later and confirm details before I make hard quotes.

so first up, W/C T5.....

Bellhousing: any late 70s BOP 4Speed housing will work I like the 76-80 pontiacs. A T5 will bolt up, and its the right depth and will correct the shifter lean. 20-100$ .... ebay landed me an excellent one for 45 shipped.

Flywheel: I have used the Stock cast iron from a 79 Buick Skylark (100$ at Vato-zone) but highly suggest you DO NOT SPIN FASTER THAN 6000 for more than a few seconds..... nobody likes a gernade by there feet. Centerforce makes an aftermarket one that goes for around 300$

Clutch: use pressure plate for 79 buick skylark with 231 evenfire and a V8 Fbody disc. The disc just needs to match the trans splines so if you have a ford trans - get ford specific splines ... just ensure that its the standard 10" unit. I think an all GM clutch runs about 179$ at Vato-zone as well.

Throw out bearing: I found the easiest to just use a Hydralic throw out from Speedway motors.... its a bit of a pain to setup, but once its in its done. 179.00

Pilot bearing: stock 79 buick skylark 231... 11$

Its that simple..... Now for fitment.... issues and ease of swapping into a G body... I have no clue.... never owned one.... Im a hybrider and S body and LUV body chevy trucks have always been my choice. I have the one out of my S10 finally but I have been having serious marital problems and havent gone much farther than that, I will show if there are any signs of thrust bearing wear or anything else when i can find the time.

A.j.

 

[bmackinnon]

A little searching goes a long way on this forum.... Dr. Frank.. has alot of good specific information, and the following threads should supply you with most of the info you need...

http://www.turbobuick.com/forums/transmission-talk/166589-manual-transmission.html
http://www.turbobuick.com/forums/transmission-talk/213887-t5-bellhousing.html

Also, pay particular attn. to member UNGN's experience.... he road races g-body's and also has very good info you should know before going into this...

Personally, I think it would be a heck of alot of fun, especially in a f-body, IF you can make it work/drive PROPERLY, and stay together.....