T56 bellhousing

[BigBlockOlds]

I'm in the process of gather parts for a T56 swap into my '87 Olds and have a question regarding the bellhousing.

I currently have a Lakewood Blowproof bellhousing that is setup for a Muncie, T-10, etc. Is it possible to have it drilled out to accept the T56's bolt pattern? If so, is there a company out there that can do this?

I contacted Lakewood about sending it to them to have it redrilled but they said they couldn't do it.

I also noticed that McLeod has a T56 with an adapter plate made to fit GM bellhousing patterns. Has anyone used this?



One last question, was the bolt pattern for the different transmissions used by GM the same? I know the Bellhousing-to-Engine bolt patterns are different but was curious whether or not the the trans-to-bellhousing bolt patterns were different between the different makes.

Thanks for the help!

[andrewb70]

There is more to it then just drilling the bellhousing for the different bolt pattern. First of all, do you have an LT1 T56 or an LS1 T56?

The main issue is that the T56 transmissions do not have a bearing retainer (snout). The bearing retainer does a couple of things. The first is that it provides a place for the throw out bearing to ride on. The second, more importantly, the bearing retainer actually centers the transmission in the bellhousing. The bolts just keep it attached, the do not align the trans. Proper input shaft alignment is crucial for proper clutch disengagement as well as shifting.

Now that I think about it, the T56 transmissions have alignment dowels that are pressed into the tranny. In theory, a good machine shop should be able to drill and properly mount the tranny to the bellhousing. You still have to deal with the throw out issue, and if you have an LS1 T56, you may be completely out of luck since the input shaft is too long for your bellhousing.

All Chevrolet block to bellhousing bolt patterns are the same.

Andrew

[BigBlockOlds]

Thanks for the info. Didn't realize there was more to it.

I was originally planning on using an LT1 T56 because of the LS1 issues you stated.

I see where McLeod makes a modular bellhousing that would adapt a T56 to an older engine. Maybe that would be the cheaper solution.

Another thought. What about a Muncie or T-10 coupled with a Gear Vendors overdrive unit?

Or, what about a TKO 500 or 600 5 speed? I believe it says they come with a GM bearing retainer and trans-to-bellhousing bolt pattern.

Thanks for the help,

[parsonsj]

what about a TKO 500 or 600 5 speed?

As I tell my kids: now you're using your head for something other than a hat rack!

The TKO will bolt right up to your bellhousing and use whatever clutch linkage you already have. No need for custom flywheels or clutches either.

You will have to mess with the crossmember and possibly the tranny tunnel. But overall, they are usually a better choice for what you're trying to do.

jp

[andrewb70]

What John said.

Andrew

[bnoon]

I totally disagree with what you guys are saying. I'd sell any bell housing you have an go with a full LT1 t56 setup, including 3rd gen F-body clutch/brake pedals (4th gen pedals are the same, but you have to cut off the gas pedal because it's attached to the clutch/brake bracket assembly in '93+ years). There are at least a couple of '79-'88 body Monte's that are running this setup over on the thirdgen.org forums (third gen F-body forums) along with a TPI gen 1 Chevy small block.

Use the stock 3rd or 4th gen F-bod clutch master and slave cylinders and the rest is pretty much a bolt in. As long as you have an '86+ gen 1 small block, the LT1 flywheel will bolt up as well (one piece rear main seals). Other than a modified trans cross member (and driveshaft depending on what engine/trans you're running currently) and slight modifications to any existing or custom center console you may have, GM has done all of the work for you. It's just a matter of knowing what parts to buy.

Without going to custom ratios in the 5 speed, the 6 speed will offer a lot better ratios and rear gearing options as well, while still maintaining a better ride on the highway with .5 or .6 final overdrive ratios depsning on the year you get. LT1 6 speeds are getting cheaper because of the mileage they would have on them by now and rebuild kits are all over EBay...

All Chevrolet block to bellhousing bolt patterns are the same.

Andrew

Except LS1 blocks. LS1's have the upper right bolt (when you're in a seated driver's position) in a different location.

[parsonsj]

bnoon,

You totally disagree with what we are saying? I think you are overstating your position a bit.

You list several paragraphs about what is needed to put in a T56: Pedal swaps, master cylinders, flywheels, speedos, etc., etc..

You claim that the TKO which allows one to bolt a standard sbc/bbc/olds/pontiac bellhousing (Remember the userid of the person who is asking the question: BigBlockOlds) up, bolt the transmission up, and use the existing pedals and linkage is more difficult. I'm not seeing it.

I can see where you might say that the T56 isn't so difficult and that it's been done, and here is some guidance. However, at best, I think you can only claim that the T56 is no more difficult than a TKO. I'd disagree ... but I wouldn't quibble.

Have you looked at what the new TKO-600s offer? Damned near perfect road racing gear ratios that allows the use of 5th gear on the track, if you use the one with .82 OD. The T56 OD gear ratios of .7 and .5 render them useless except for highway cruising. For track use, the T56 should really be considered a 4 speed.

Here's some more advantages for the TKO:

Higher torque rating
Lower weight and smaller size
Standard clutch setup
23 possible positions for shifter
Standard and VSS speedo arrangement
No CAGS
Available brand new for less than $2K

If you happen to already have a T56 lying around, then maybe it is a better option in terms of fabrication, money, and performance. If you are starting from scratch, the TKO is the way to go.

jp

[bnoon]

You claim that the TKO which allows one to bolt a standard sbc/bbc/olds/pontiac bellhousing (Remember the userid of the person who is asking the question: BigBlockOlds) up, bolt the transmission up, and use the existing pedals and linkage is more difficult. I'm not seeing it.

Oops, Big Blocks Olds... missed that part. Thought he had a more common Chebbie small block. Prolly a bit harder to get a bell housing/clutch/flywheel...

The part about the 3rd and 4th gen F-body pedals remains true though. They are almost a bolt in for the intermediate chassis, only needing one hole to be knocked out in the firewall for the master cylinder. Loosly bolt up the pedals to the existing pedal bracket bolts to locate that needed hole, pull the pedals back off, drill the hole with a hole saw, and you can bolt it together. If you have a cable type clutch (a little more rare in the aftermarket) you can use early 3rd gen pedals (I believe '82-'84 F-bods) and they bolt up the same way (I did this to an '82 Buick Regal for circle track racing).

Of course if you're talking aftermarket transmissions, you can get any ratio you want to pay for.

[Mkelcy]

John: The Aftermarket T56 actually has a nicer gear spread than the TKO, ends up with a .64 sixth for a nice over-overdrive gear, is also a bolt-in using mechanical linkage components and should cost about $2k also. Package is larger and slightly farther to the rear of the car and power capacity is lower, but still a viable option and one I love on the freeway with my 4.11 rear gears. The speedo is mechanical, but there are readily available adapters if you need VSS and there is no CAGS in the Aftermarket T56.

[RBrock]

You can get a kit that will replace the bellhousing that comes on the LT1 T56's with a new front plate that will allow you to bolt it to your bellhousing. It also includes a different input and bearing retainer. Basically it makes the LT1 T56 look like a GM aftermarket T56 They run about $600.

You can read some info here:
http://www.5speedtransmissions.com/t56_early_gm.html

One thing to be on the look out for, is your crankshaft drilled for a pilot bushing? Since the good Dr. Olds had seperate crankshafts for automatic and manual.

Ray

[BigBlockOlds]

One thing to be on the look out for, is your crankshaft drilled for a pilot bushing? Since the good Dr. Olds had seperate crankshafts for automatic and manual.
Ray

I don't believe it is. The engine was out of a '76 Custom Cruiser station wagon with a TH-400, so I highly doubt it was drilled for a manual transmission. From what I gather, it was rather a hit or miss deal on whether Olds drilled an auto crank with the manual trans provisions.

But there is a solution:

http://www.supercarsunlimited.com/trany/adapter.htm

Thanks for all of the help.

[BigBlockOlds]

Doing a search within one of my Oldsmobile forums I found a company called Weir Hot Rod Products that make a T56 conversion kit for the BOP guys.

Here's a link:

http://www.weirhotrodproducts.com/id1.html

Has anyone used their products for a swap?

Thanks,

[MATE]

I have the Wier Kit and I was going to use it behind My SB olds in my G-body Cutlass. Since then I have decided to go to an Alternate power plant. I'll take some pictures of the kit and post them.


Mate

[SmooveG]

What were you going to use for a master cylinder with the Wier kit? I spoke
to Bob Weir and he suggested a Tilton master but I was told on another board that it has a straight flange and for the G-body you need an angled one like the F-body but that doesn't have enough force for the wier throwout.

G