89_LT1_IROC

Okay, I currently own an IROC-Z that has received a heart transplant-- the donor was a 1995 LT1. I've been running the WC-T5 for about two years. The T5 has held up great to 300 rwhp / 350 rwtq. I really want to start powershifting when I race this season, but I don't want to ruin the T5 because it's a prefectly good tranny. I recently acquired a T56 from a 1999 SS.

So far, I know that I will need to switch torque-arms since Im already running a spohn aftermarket piece. Also, I need either to shorten my driveshaft, or buy a new one, and I need an adapater plate to attach the T-56 to the T5 bell housing. My main concern is the speedometer. I'm currently using the stock gauge cluster, and would like to retain the stock unit. I've seen several posts regarding a converter from JTR that converts the signal from electronic to mechanical.

If I've mistated, or forgotten anything, please feel free to help me out! I would like to get the tranny in before summertime.

Thanks

Trux

Just wondering but not sure but won't the bell housing from that tranny bolt up to your motor?

I am pretty sure you will need a new transmission mount bracket.

Good luck

87RS402

The 99 is a LS1 trans, It will not bolt to your engine and I seriously doubt that the adapter plate will bolt to the trans either. It has to be a 93-97 trans or an aftermarket, not many other options.

I know this has all been covered before so you might try a search.

Trux

There is always a way.

look for a bell housing around the lakewood site.

They might have somnething

Good luck,:hail: :hail: :hail:

89_LT1_IROC

87RS402:

Aren't the LS1 T-56's TTC Trannies (Tremec)? When you say "aftermarket," I'm not entirely sure what you are speaking of. Spohn offers these Tremec T-56 "aftermarket" transmissions as direct bolt-on for third gen camaros. So, I don't see why this tranmission wouldn't work.

87RS402

First Lakewood does not make a bellhousing for a LS1 T-56 to an older sbc, if they do it's a brand new product that just came out.

Second, all T-56 trannies are TTC's. I believe one of the major differences in the LS1 trans is the input shaft as well as the bellhousing pattern. The aftermarket box that Spohn sells is a LT1 T-56 with an adapter plate and a different input shaft that is meant to bolt right up to a T-5 bellhousing and clutch setup, I have one less than 10' from me right now that I procured elsewhere for substantianlly less. The fact is that LS1 transmissions have design differences that keep them from being used on older engines just like the Mustang T-5 has design differences that keep it from working in an F-body.

All T-56's are not equal so don't assume that just because they share the same model type they interchange.

Matt87GTA

The input shaft is different on LS1 T56s and so is the clutch design. It has been stated many times that it cannot be made to work on a SBC without modifications. An LT1 T56 on the other hand, is a direct swap onto a SBC (with its bellhousing and hydraulics anyways).

Do yourself a favor and sell that trans to an LS1 owner and find an LT1 box.

89_LT1_IROC

Well, this really bites. Oh well, I guess I'll have a backup tranny for my 2000 SS

BOTTLEDZ28

iTrader: (9)

put it on ebay it will sell like hot cakes. then get the money and buy the lt1 tranny

89 RS W/ T-56

I run a T-56 from a 95 Trans Am. I do know that the LS1 T-56 is possible. Go with the LT1 flywheel and clutch(pull style clutch) and bellhousing and change the LS1 T-56 input shaft and front transmission cover. Get the LT1 master/slave cylinder and bolt it in. My torque arm bolted right to my LT1 T-56 and it would have also bolted to an LS1 T-56. I am not sure what set up you have. A custom crossmember will be needed. I got mine from SPD.
:hail: T-56!!!!!!!!!!!!!

Speedometer on the other hand is a different story. I haven't decided what to go with yet, I have not had this awesome transmission that long.

REVLIMIT

I thought you could just bolt up the bellhousing from the 93-97 trans up to the LS1 t56 O_o

89 RS W/ T-56

The clutch fork needs the LT1 front transmission cover to work.

Matt87GTA

And the input shaft for the LT1 pull style clutch.

Anak

I believe you can run an LS1 T56 behind a regular small block. I am rounding up the parts to do it on my '90 GTA. The key to it is to get a bellhousing from Weir Hotrod Products. You can call Bob Weir at (707) 647-0513. He makes a bellhousing for this specific purpose. Don't write off your project just yet.

Matt87GTA

Not to be an a$$, but you need more than just a bellhousing to mate the LS1 version T56 to a SBC.... The clutch is an entirely different design as well as the flywheel and input shaft.....

Anak

Stop and think about it. What does the transmission care what clutch or flywheel are in front of it (other than spline count)? The clutch and flywheel are issues of the bellhousing and block respectively. All the transmission requires is a divorce from engine RPM in order to shift.

Yes the LS1 uses a different clutch and flywheel (although its clutch is actually more SIMILAR to a regular small block than is the LT1 clutch. Weir's bellhousing accommodates the standard small block (or big block for that matter) flywheel. That's part of the design. That's the purpose behind the existence of the product.

As far as clutch design goes, the LS1 returned GM back to the older style clutch (push, rather than pull) but with a hydraulic throwout bearing. This is not a new invention. Racers and custom builders have been running hydraulic throwout bearings with push style clutches for years. If you are already running a hydraulic clutch system (vs mechanical linkage) the swap should be relatively straightforward.

Weir's bellhousing will accommodate the LS1 hydraulic throwout bearing, or Weir offers his own hydraulic throwout bearing for use with his bellhousing along with a Tilton master cylinder. Weir's throwout bearing requires a master cylinder with a 1" bore, so using the stock master cylinder will not work. To hook up the Tilton master cylinder looks like a pain, so I am looking into the McLeod version of the LS1 master cylinder and throwout bearing.

YOU MAY BE RIGHT, but I think, rationale as you have now read, that this swap should work. The place where I am MOST concerned is the extra 5/8" the LS1 has. I have the Spohn crossmember and torque arm, and they assured me those will work...but I won't know for certain until I get things into place. Likewise the question of the driveshaft. Neither of those issues should prevent the swap--they will just add more work/cost to it. Considering the difference in price between an LS1 T56 vs and LT1 T56 I am willing to try this route. If you don't, that's great. You will help keep the prices down on T56s for me.

Matt87GTA

Well I already have an LT1 T56 in my GTA so I won't be helping you out there on the prices . And I am completely aware that the actual design of the clutch has no bearing ( ) on things unless you are looking for a direct bolt in - and even then you are OK with the hydraulic TO bearing since our cars have hydraulic masters in them. And the transmission gearbox may not care what flywheel it has in front of it, but the engine certainly cares what flywheel is behind it!

What is the price on this custom bellhousing? And does it create the proper spacing between the gearbox and the crankshaft for retention of the LS1 input shaft? What about the flywheel? Can you use an LT1 flywheel with this setup? How about LS1 clutch parts with the LT1 flywheel?

My point here is that there are still questions about this above and beyond what your original post contained answers to. The jury is still out on if this is cost effective. I was posting to clarify for others, not to prove you wrong.

But you are really onto something if this all works out. It sounds like a really good plan if the cost of the custom bellhousing is low and the LT1 flywheel with existing mass-produced LS1 clutch parts can be used....

- Out here.

Tricked-Out-Toy

iTrader: (1)

hey how much did that bell housing kit cost?

drain89

iTrader: (10)

The T56 Has 6 main versions with a few different gear ratio spreads for those versions, I'll list them in order as they appear:
1) 92 up Viper (strongest one-can be modded to fit GM or Fords, contact D&D or Forte's for more info)
2) 93-97 LT1 camaro/firebird-93's and some 94's were 3.36 1st gear, but after that they went to 2.96 and 2.66 1st geared versions. The 2.96 have the highest torque capacity and 3.36 ones the lowest)
3) Aftermarket T56 model-Released by Borg Warner and then by Tremec when they purchased BW in 97 IIRC. Offered for custom and retrofit applications. More expensive than the LT1 version and much harder to find a used one.
4) C5 corvette-this is completely unuseable in our cars or anything else for that matter since it's jointed to a transaxle and has a torque-tube instead of a bellhousing.
5) LS1 camaro/fbody/Holden/Cadillac T56-LS1 specific, doesn't mate to SBC's without considerable mods/expense.
6) 03 and up Ford Mustang Cobra-for 4.6 & 5.4 Modular motor family.
Of these, the easiest and cheapest to swap for our cars is the LT1 camaro version. The aftermarket one isn't bad if you're using a 2 piece rear main seal crank and flywheel, but requires you shorten your driveshaft and torque arm whereas the LT1 version doesn't.
The LS1 version requires you change it to a LT1 style bellhousing or get an adapter plate and traditional style bellhousing. Plus you'll have to change the input shaft to the LT1 style. I've heard that lakewood is working on a modular style bellhousing that allows you to swap them in but sounds like an un-necessary and expensive solution when you'd have a better and easier product to work with by going with the LT1 version.
The older T56's that were made by Borg Warner are stronger. Don't believe me.....just ask anyone who's owned LT1/T56 f-bodies AND LS1/T56 f-bodies. The LS1's guys have way more problems with theirs. Seems like some corners were cut when it went to Tremec IMO.
Starting with a LS1 version and modifying it seems like pissing up a rope to me, so do yourself a favor and sell it and buy a LT1 version. If you're smart about it you'll get more for the LS1 tranny than what you'll pay for the LT1 one. Plus you'll spend way less swapping it in. There's enough LT1 version T56's around that they're fairly easy to find.
Or if you plan on making lots of power, call D&D and get a modified/blueprinted version or even better a Viper T56 that's been modified for an LT1 application and you'd have to build one helluva motor to tear it up!
Good luck either way!

Hodge

My friend has a LS1 T56 in a second gen. He is still using his stock style cable operated clutch too. He used a stock type bellhousing(4-speed 2nd gen style) and bought an adapter plate that goes between the tranny and the bellhousing. see info below.


Mccloud makes a 1/2" adapter plate (PN 8-207 $215.39 from summit) to bolt the LS1 tranny to a GEN I SBC.

Now this PN is for bolting it to a Standard SBC bell housing. The T5 bellhousing tilted the tranny at an angle. About 45* if I remember correctly. McCloud may make an adapter to fit that bellhousing to the LS1 T56 or you may have to use an old style one. lakewood makes bell housing that are the old style(non-tilted) and can accept the hydraulic style clutches.

It can be done. Have faith.


Hodge

wp4

can one use a regular lt1, or even ls1 t56 (not the aftermarket one), and use an adapter plate? or will the input shaft be too short then? Does the af/m one have a special 1/2" longer input shaft?

jmd

iTrader: (4)

A few bolt holes don't line up, and you still have no attachment for the fork pivot block, so that's *not* a solution. And yes, I have tried it.




All you need is a spacer plate. This allows LS1 T56 trans., bell, hydraulics to be used behind a SBC & "normal" push clutch. Same functionality as a Weir piece, less money.

And yes, I have looked into it. I have one for sale at the moment.




Yeah, their 84-92 F bell has straight up and T5 patterns in it both.

-Matthew

askulte

What are you guys doing about the LS1 flywheel? I didn't think it bolted to either the 1 piece rear mainseal TPI/LT1 or 2 piece older rear mainseal cranks. Don't the pilot bearings also have different dimensions? I'm just curious how the LS1 T56 can have the input shaft mate with the non-ls1 cranks.

TKOPerformance

McLeod has a modular bellhousing that will easily allow the LS1 T56 to bolt up to a traditional small block.

Working up a hydraulic throwout bearing system shouldn't be much work (heck you might be able to use the stock LS1 4th gen hydraulics, the LT1 slave/master is a bolt in).

The LS1 input shaft is slightly longer. The bellhousing will take care of the relationship with the clutch/pilot bearing.

You need one of Andris' crossmembers. You might need to slot the hole to move th mount point back a hair.

All things considered this is no longer the nearly impossible swap it once was. If you can get a cheap LS1 T56 in good shape it could be worthwhile. I still think a '94-'97 F-car box is a better bolt in swap choice, but deals on parts that aren't quite right do come along, so don't just discount the LS1 T56s.

Also, as a point of reference, my T56 was built by Borg Warner prior to the sale to TTC. It was built in the USA, not Mexico like the TTC T56s. Earlier T56s are Borg/Warners. Later ones are TTC. The design is identical. Borg/Warner sold their transmission division to TTC.

jmd

iTrader: (4)

• Not using it unless using a Gen III/IV engine.
• Right, it doesn't.
• Nope.
• Same pilot dimensions. Same spline count & o.d. on the input splines.

askulte

Ah! So, we can move the T56 rearwards a bit with either the adapter flange or a custom bellhousing to take care of the longer LS1 T56 input shaft, and use a standard SBC clutch and a hydraulic throwout bearing since the input shaft is the same, except for being longer. Good to know. Thanks.

wp4

jmd, how much for that spacer? email to:

dhutton@gmail.com

thanks!

AKToast

Summit:

MCL-8703-12 SCALLOP RING $81.39
I believe it also requires:
MCL-870722 DOWEL PINS $18.39

slayer2000

iTrader: (1)

just out of curiousity, How's the lt1 style clutch feel? I read in car craft this month that it doesn't really engage properly in a thirdgen. I can't really see why that would be if it was setup correctly. I'm going to a t56 this winter and I'd like to make sure I got as many things sorted out as possible before I start.

TKOPerformance

Hogwash. It feels like a hydraulic clutch.

slayer2000

iTrader: (1)

That's about what I thought. Like I said,if the clutch is setup right I just couldn't see what difference it would make.

Tricked-Out-Toy

iTrader: (1)

I have the LT1 style in mine and I cant tell a differents between my old T5 and the new T56. I dont think those guys know what there talking about, of all the car mags out there I think car craft is the worst, over the years ive caught tons of miss information they have printed. If your looking for a great mag read up on GMHP, that mag kicks ***, even hot rod is better than car craft. so sorry for the rant

TKOPerformance

I have been a long time Car Craft reader, and in all fairness it is the most entertaining read out there. That's what I love about it; it's spirit. They definately let some stuff slip through the cracks though. I've noticed several slip ups over the years too. Their stance on imports is a little annoying too. I fully agree that all of the fart mufflered, 9-degrees of negative camber from improper lowering, neon lighted, six color junkers out there should be rounded up, taken to the crusher and sent back from whence they came. However, that isn't all there is out there any more, and neglecting the technology that modern imports present is foolhardy. Reality check, my bone stock WRX runs quicker than the vernerable 5.0 Mustang did stock, and outhandles is too, all while sipping gas to the tune of 30MPG highway. This isn't theory, I've owned both cars and run both. The WRX comes out on top. Yes, I love my instantaneous torque American V8s, and own several, but I'm also realistic about what is happening out there. As a daily driver a V8 is brutal with gas at $3+ a galllon. The days of the V8 being relegated to a "rich mans" car are coming back, which is fine, because the current generation of 4 and 6 cylinder engines are making as much or more power than the V8s of only a decade ago.

Anyway, CHP and Hot Rod are both good mags too. Hot Rod is always on the cutting edge of technology, which I like. Car Craft has a braoder appeal though, because it showcases all makes and models, not just Chevys. For those of us who own a mongrel fleet it can give us info on all of them, you just have to be careful to double check what you read. But hey, that's what any informed consumer should do anyway...

UnstableAviator

The Wier bellhousing is the way to go, even though it is a bit more expensive. He makes a bellhousings to mate any T56 (Lt1, LS1, aftermarket)to pretty much any chevy engine.

I purchased the bellhousing kit, hydraulic TB, and Tilton 1" bore master cylinder from Wier and installed it behind my 2 piece rear main seal 383 using a standard external balance flywheel and 11" Mcleod pressure plate and 26 spline disc. The setup resulted in a factory feel, very smooth shifting T56 and a stout assembly that will hopefully survive for years in my car.

Using the Wier kit, you can use any clutch/PP combo you want, even up to a 12" diameter clutch. The only real difficulty is the mounting of the Tilton master cylinder. I was fortunate to have access to my father's shop and his skills as a fabricator, and he made a bracket to hold the cylinder in place that actually bolted into the stock location. It isn't easy, as the angle and length of the tilton make it a tight fit. The good thing is that the stock pushrod attachment can be used on your pedal, as the stroke for the stock cylinder and tilton is the same. I just modified the existing clutch pushrod with a threaded end to accomodate the tilton. You'll also have to count on making a few trips to the parts store for fittings to run the hydraulic line to the throwout bearing.

TKOPerformance

Interesting, but that seems like a lot of work when the stock LT1 components all bolt right in and work just like factory pieces. Now if you got a good deal on an LS1 trans it may be worthwhile.

Tricked-Out-Toy

iTrader: (1)