I have an 86 iroc z with an 88 350 block. I just got a t56 from a 2002 trans am for it, with bell housing and throw out "bearing". I know this has come up previously, but I still have some unanswered questions. 1) Do I need flywheel, clutch, pressure plate from a t56 car? 2) Can I use the hydraulic cylinder from my t5 for the t56, or do I need one from a t56 car? 3) Will bell housing bolt up, with which parts, and be "lengthwise" correct? 4) I know I have to cut 2" further for the shifter, but is there anything else I need to know before I get started? I want as few, if not none, surprises when I go to put this in my 86 Z28. Thanks in advance for any help. drjohn981

your not going to be able to use that trans the way it is, the input shaft for an Ls1 car is different from an LT1 car. Youll have to either get another trans or do some adapting to make it fit plus you may ave to change the input shaft alltogether so you might be better off getting another trans from an Lt1 car.

I'm in no hurry here. Can't the shaft be swapped? Tranny has to be opened up to check 2nd gear synchro anyway. This may not go in until '07, so I have plenty of time. I just want to have everything needed when I get ready.

If this tranny CAN'T work, then I'll see about swapping it for a t56 that will.

drjohn981

Before you sell or swap anything on that trans...look into the McCleod adapter plate #8-207!

Some reading to help explain this

http://www.thirdgen.org/techbb2/show...22#post2715922

An LS1 T56 can work with your bellhousing and clutch setup!

Thanks for your input. I may look into that adapter. I'm still curious though as to what else is needed - flywheel, clutch, pressure plate, hydraulics, etc. etc.

As I said, I have time to try and get everything, I just don't know for sure what EVERYTHING is!!

I cannot see why you could not use the flywheel, clutch, pressure plate, hydraulics,and bellhousing from your T5 setup.

In addition to that get yourself the McLeod adapter plate #8-207 and pilot bearing #8617 (A new discovery yesterday..and is necessary!),an LS1 T56 and start swapping.You will need to enlarge the shifter hole,get the driveshaft shortened,and possibly shorten the torque arm a little bit,add in a T56 crossmember from any of the available ones.Some tweaking here and there will be needed.But that comes with swapping in non stock parts with aftermarket parts so thats expected!

I will call mcCleod and find out if there's anything else required for the swap. So far it looks OK.

Also there is Weir Hot Rod Products that looks like they will make a bellhousing to match the LS1 to the '88 block. After talking to McCleod, and seeing what else might be needed, I will contact Weir and see what the cost is for their bellhousing and compare.

Talked to McLeod tech today and he says that if you are using the #8-207 plate and swapping an 98-02 LS1 T56 to an older block,you NEED the extended pilot bushing #8617.

This is due to the fact that the plate is really made to adapt the aftermarket T56 to older bells.The difference is in the total input shaft length,trans would have to be pulled apart to measure this.The aftermarket trans input shaft is 11.125" long and the factory T56 length is 10.625".This bushing gives you roughly .400" more input shaft support than a standard pilot bearing/bushing.He said .500" would be ideal but give or take 1/8" will not hurt it.

Just an FYI.

Explain to me why you'll need to shorten the driveshaft, and by how much?

I mean if the LT1/LS1 drivelines work in our cars..... and the LT1 t56 bolts into our cars and needs no driveline modification..... setting the LS1 trans back from the T5 bellhousing with that adapter shouldn't need the driveline shortened unless you've got the driveline way up in there in the first place.

Or are you talking about the early thirdgens that had longer drivelines to beginwith because of the shorter 200R4/Th350 short shaft?


As it sits right now... my driveline is about an Inch too short. It's the aluminum LS1 slid into a TH350 Long Shaft. I'd hate to have to find something out with that... like ditching it for a steel one since it's $$$$$$$$ to change the length in an aluminum and I've got new joint and balancing in mine.

You are possibly correct.You may not have to shorten the driveshaft on a T5/700r4 swap as it should only add another 1/2" with the adapter.I just wanted to point out it may be a possibility on any swap.I have to shorten my DS as it was from my T10 and a few inches longer than the later 83-92 models.Rear axle choices may effect this as well.When I installed my Moser 12 bolt I had to have my DS shortened with all else being in the factory stock locations!Either way you will have to measure to be sure.

With the TH350 in my car... the LS1 Aluminum driveline was 1" too short. Driveable but not ideal.

Now it's 1" too long with the LS1 T56/T5 style bellhousing/McLeod adapter.

Will get better measurements when I calm down. That really pissed me off. LOL

Figured it was time to put the tools away for the day.

Well, I got a 10 bolt 4.10 posi rear from a guy off the board in the Roc now. This replaced the 3.23 pegleg that was about to grenade.

I have Vortec heads, 1.6/1.5 mixed set of roller rockers, the ls1 t56 tranny, and to top it all off - an 8 3/4" mopar rear with 4.30 gears (modified to bolt into a third gen) that will all be going in as a package, but probably not till next year - or sooner if I blow the current 10 bolt. This set up will in all likelyhood be the only one of its kind!!

Still waiting for the Mopar rear to arrive. Now I have a post that is less than 2 weeks and one day old.

So your using t5 pedals hydraulics and bellhousing on a ls1 t56? are those adapter parts expensive?

You need a pilot bearing for abour $40 special from McCleod, and the Adapter plate itself was about $250.

Then you have to build a bracket for the shifter that moves the stick itself forward and over to the left by about an inch in either direction so it wont hit the T5 shift plate.

So if i understand this correct to swap from a t5 to a ls1 t56 i need a adapter plate, piliot bearing and to move my shifter or make the hole bigger?

thx

From what I've been able to find out - you need adapter and extended pilot bushing from Macleod; you will need a fabricated or aftermarket trans mount. I think you can use existing t5 clutch, pp, throw out, linkage, and hydraulics, as you'll still have the existing t5 bellhousing. You'll have to enlarge shifter opening because of new location of shift lever. You may, or may not have to shorten driveshaft according to where it all ends up.

If anyone has more to add - PLEASE DO!!

Thanks,

drjohn

I realize this is and old thread, just trying to help add info. I am using a LS2 GTO T56 behind a sbc. To do this I had my input shaft shortened .400" and the mid plate machined to accept a aftermarket ram hydraulic throwout bearing. This allows me to use the stock sbc flywheel and clutch kit and saves the 25lbs of adapter plate. I will be using the LS bell housing until I can afford a Quicktime one. If I ever go to a LS engine I will just make a spacer to move the throwout bearing back out to its original depth and use an extended pilot busing to make up for the the shorter input.

Bell housing depths

T5, Muncie etc. = 6.3"
LS1 T56 = 5.5"
LT1 T56 = 4.9"

The rear of the engine to the tranny mount is

T5 = 22.3"
LS1 T56 = 26.5"
LT1 T56 = 25.9"
Aft T56 or LS1 w/ Adap. plate = 27.8"

Length to tail shaft w/ bell

T5 = 31.3"
LS1 T56 = 31.9"
LT1 T56 = 31.3"
Aft T56 = 33.2"

Rear of engine to shifter

T5 = ?
LS1 = 29.4"
LT1 = 28.3"
Aft = 27.9"