Swapping from BBC to LS3, Can I Keep the T56?
 

I have a 68 Camaro and I would like to change out the BBC to an LS3. It currently has a Magnum T56. Would I need to purchase a complete new tranny? If not, what exactly would I need to change?

Thanks in advance..

prob can use the same bellhousing less one bolt or but t56 ls bellhousing. There threads where guys just change flywheels and are ok.

I converted my T-56 from an LT1 version to an LS version, There is a kit i bought from a company back east (Rockford i believe), bout 400$, includes a new input shaft, shims, and front "collar" which you'll need. I saw an article about this, either popular hot rodding or chevy hi-performance, which is why i did it...

http://www.gmhightechperformance.com...on_conversion/

I'm pretty sure if you have an t56 behind the bbc you'll need a different input shaft (as the final length is different) and collar, the lt1 tranny bolts up to a sbc, and the bolt pattern is the same for a bbc. You'll also need to confirm your bellhousing (you'll need an ls one obviously)

http://lakewoodindustries.com/ls1-to-ls1-t56-chevy.html

http://lakewoodindustries.com/ls1-to-dodge-viper.html

?????

As stated above, you'll need to change your input shaft, front plate, and bellhousing. The input shaft change out is really easy. I've got pics of this in my build thread. You'll need a micrometer set to verify preload, when reinstalling the front plate. The preload is set with shims under the bearing race inside the front plate. I did mine myself, and had about $600.00 in parts. I'll tell you however, the input shaft is usually hard to obtain. Most tranny parts dealers have to back order the part.

So truuu, my mechanic buddy handled that part, and well, wasn't set right and the car was very difficult to shift...had to pull, redo about two to three hours

But if you look on that link on the gmhighperformance, that company has all the pieces in stock, i think i paid around 400 +/-. But it all depends on your bellhousing situation, thats the final dim

I don't think you'll need to do anything to the T56. Confirm with the vendor you got the T56 from.

Mike, did you move?

[Hijack]Yup. I've been in Walla Walla since January of this year. It's been wonderful up here, incredible views, cool nights even in the depths of summer, great wine, great restaurants and 1,600 feet of shop space.[/Hijack]

Congrats on the shop space Mike, that'll make life a lot easier. As far as the trans Frank, you'll need the correct bellhousing to make that work, trans should be fine as-is. Quicktime, McLeod, and others all make the swap bellhousings I believe.

I'm glad everyone didn't think my article was pointless. I got a lot of flak on that article for some reason.

So the t56 magnums have a different input shaft length than the std, t56?

There are two "standard" older T56's for Chevy's - the LT1 T56 and the LS1/Magnum T56. The LT1 T56's have about a 5.5" input shaft - engine to bell housing to bell housing to transmission mounting surface; the LS1/Magnum's have about a 6.5" input shaft measured the same way. The Magnum should bolt right up to an LSx engine with the right bell housing and pilot bushing.

You are correct. The lt-1 t56 will bolt up to a sbc, or a bbc, with no problems.
The LS-1 t56 won't bolt up to a sbc, so I'm guessing the op has a t56 magnum built for a sbc/bbc application, which as you stated, has a shorter input shaft. I know that I had to convert mine over.

No. The LS1/Magnum T56 has a roughly 6.5' input shaft which will work just fine with an LSx engine, given the correct bell housing.

You mighta got some flak for that, but out here in Kali, your secrets out. The guy i sold my zz3 to bought an LT t-56 and i couldn't be happier as I had my t-56 "magnumed" rebuilt right before my LS conversion and i was sooo relieved when i found out i could do this ( i was afraid i was going to be out another 1600)

So ya, thanks for that article. Watched your blue hour build too, absolutely love your car....

back on topic,,,,sorry for the diversion......Mike

Well good! I'm glad someone got something out of it. I figured for $400 and if you have an LT T56 laying around, it only makes perfect sense.

The one I built for the article was one I had from my old build. I converted it and sold it for double!

An LS1 T56 will bolt up just fine to a SBC/BBC with a 0.5" thick mounting/adapter plate and the original Muncie type bell housing and mechanical clutch linkage. You can skip the adapter plate if you use a hydraulic clutch linkage and a T56 specific bell housing for the SBC/BBC.

Correct again. The standard GM t56 bell will work, as well as others built for this application.

I've seen this done, but never in high power applications. I wouldn't run it, ever.
Back to the original question from the op, he never stated he had the adapter plate, and associated hardware. He simply wanted to know if his tranny that's currently behind a bbc, would work behind an ls3.

WOW, thanks for the overwhelming response and information. I truly appreciate it. :cheers:

So then buying the Lakewood/QuickTime bell housing and pilot bushing is all I need? I am purchasing the Katech ZR1 to LSx clutch and I am attempting this project myself so excuse my ignorance.


What about the throwout bearing? Would that change as well?
I have been out of the scene for a while and I am motivated and excited to return.

I am going from this:
http://i42.tinypic.com/34y4ltd.jpg


TO THIS:

http://i43.tinypic.com/2pp0ww2.jpg
http://i43.tinypic.com/15s3fv5.jpg
http://i42.tinypic.com/20ibf4j.jpg

I'm not sure what you find unacceptable in a 0.5" thick steel plate between the transmission and the flywheel. http://www.summitracing.com/parts/mcl-8-207

Lots of people have run them and I've never heard of a failure. It's also the only solution that allows for the possible use of the OEM clutch linkage in a SBC/BBC application.

You'll need a factory hydraulic throwout bearing, a master cylinder and associated plumbing. Lots of folks adapt the OEM master, there are also after market masters that have some adjustability http://www.summitracing.com/parts/mcl-1434002/overview/.

You should be aware that there are two styles of pilot bearing that fit LSx engines - one is the same size as the SBC/BBC version and sits in a recess in the crankshaft, the other is about 1.5" (best guess) in diameter and sits in a larger recess in front of where the smaller pilot would go. Obviously, the choice of pilot could affect the depth of the required bell housing. You should confirm with your bell housing vendor which pilot you need.

4musclemachines, checkout the detailed clutch install in this thread. The zr1 clutch complicates everything even more...

https://lateral-g.net/forums/showthread.php4?t=39752

Dale covers all the details.