ninetyfivevette

Over the next few weeks I will be aquiring a T56 tail housing to see how feasible it would be to create a new tailshaft housing which is compatible with the Corvette to allow the T56 to bolt up to the factory torque arm. It will be machined from 6061. It will basically look like the existing tailshaft housing, except it will obviously have the mouting on the right side for the torque arm. It will be designed such that no modifications will need to be done to the existing torque arm, but I might put in another set of holes for those that already have D44's or want to upgrade to one without having to get a new torque arm or modify their's as well.

I am for sure going to do this for myself, but if there are people that would be interested, I will keep people updated.

Mike

Raistlin

awesome!!!

sounds like a big project. keep us updated on your progress.

ninetyfivevette

I will defiantely keep people updated and keep a picture diary. I am having a friend in my engineering group do the mechanical engineering, and then I will have it CNC'd in our shop. My buddy said it would be a piece of cake (actually 6061 :) ).

Mike

Rich B.

I am interested. Please add me to your list! :yesnod:

What flywheel, clutch, pressure plate, clutch cylinders, shifter, etc do you plan to use?

You sound like you're changing over from an automatic...All C4 manual trans already have dana 44s...

It would probably be much easier to fabricate an "L" shaped bracket to adapt the existing tailshaft housing w/bottom mount to the side-mount torque beam...

Sharky Guam

I just converted our 86 to a TH400 trans. We broke our second 700R4 trans in a little less than 6 months. So the TH400 went in. I fabricated a mount using the stock tailhousing. I used the stock lower mount holes, but I welded another tab on to the top of the tailhousing to add strength.

So far, the TH 400 is working quite well.
:cheers:

Rich B.

...Pictures, Sharky! We want pictures!!!... :D

ninetyfivevette

What flywheel, clutch, pressure plate, clutch cylinders, shifter, etc do you plan to use?

For my application (not very high performance) I will probably go with the following:

Flywheel: Z28
Clutch/pressure plate: Z28
Slave cyl.: T56 (Z28's)
Master cyl.: Corvette (this arraingement requires a custom line or adapter)

Shifter: Custom offset to work with the Corvette's interior.

All C4 manual trans already have dana 44s...

I am very aware of this, but some people with automatics have already converted to a dana 44 or would like to convert someday.

It would probably be much easier to fabricate an "L" shaped bracket to adapt the existing tailshaft housing w/bottom mount to the side-mount torque beam...

This very well may be true. Until I can actually see one in person, I do not know. For me, it doesn't matter since my friend has volunteered to do all the hard work (create the solid model to be machined). You definately could be on to something there though because the Camaro/ Firebird does use a torque beam, so I might just have to make a torque beam that looks like an F-body unit and a Y-body spliced together. Hopefully in my internet research, I can find more detailed pictures to see how feasible that is, because that would definately be the easiest!

tpi 421 vette

Wouldn't it be easier to use a ZF 6 speed and related parts?

Nathan Plemons

A T-56 can be had for a dime a dozen, and ZF6 is a $3000 minimum for a used one. Personally I think the ZF6 is the better tranny and yes it would be easier, but there are some benefits of using the T-56, such as not having to use the dual mass flywheel, etc.

T-56 is a good tranny too. Keep us all updated!

MrNuke

You sure T6061 alum is gonan be strong enough to support the strain we will be putting on it?? My father's shop works with it all the time, and it's not exactly a VERY hard metal..

darkcarn85

Would this allow the replacement of the 4+3 as well. If so I'm very interested.

Rich B.

Here's where it gets interesting...I did a quick look around the Web and looked at some sites...They say the '94 & up Camaro/Trans Am T-56 is rated for 450HP, so that's the one you want, not the early ones...And the T56 uses a pull-type clutch cylinder, like the ZF, so that shouldn't be too difficult to adapt...

But there's some machining required (?) to the speedo drive, and of course the trans mount...

Here's a couple sites:
http://www.drivetrain.com/transmanualT56.html
http://www.sallee-chevrolet.com/Borg...bwt56pics.html
http://www.z28.com/installations/trannyconvert.html
http://lakeariel.net:8081/impala/6Speed/6SPEED.htm

...Oh, yeah...The dime-a-dozen...I took a quick look at eBay, and 94 & up T-56's seem to match ZF prices...My idea of a dime-a-dozen is $250 - $350...Complete... :D


[Modified by Rich B., 5:32 PM 9/27/2002]

Rich B.

Here's another site with some good info...
http://www.thirdgenfbody.com/news.php?story=1

Note that they mention there are over 30 different types of T-56 transmissions... :eek:

Here's a specs page from the people who make the T-56...
http://www.ttcautomotive.com/products/T-56.asp


[Modified by Rich B., 6:39 PM 9/27/2002]

ZBRA

The T56 uses a different type of VSS than the ZF or 700R4. You will have to use a conversion box. I have done numerous transmission swaps.

I have put a ZF6 in a '91 Z28 that came with a 700R4
I have put a T56 in that same '91 Z28 after pulling the ZF6
I have done a few T56 swaps in 4th gen F-bodies that had 4L60Es
I have also swapped T56s in LS1 F-bodies.

If you are going to use a T56, I suggest the '93-'97 LT1 T56. You will never get the '98-'02 LS1 T56 to work without major modifications.

Also, the '93 had different gear ratios than the '94-'97

Shifter location will be a problem when putting a T56 in a C4. It will sit too high and too far to the right.

Good luck.

SSLT1KID

keep me updated! im hoping to start thesamwe converion using the tranny out of my wrcked Camaro. let me knw how it goes fr you. :seeya :chevy :seeya

Rick93Z07

The topic title shows much optimism....I wish you the best. I watched a talented mechanical engineer who had access to metal fabricating and welding equipment create a basket case out of a "similar" C4 to Tremec project. He was unable to adapt it without radically modifying the car and transmission housing. The torque arm mount must be beefy, if you expect it to hold up under typical Vette owner abuse. The wide C4 tires and 50/50 weight distribution creates tremendous force. Global West discovered torque arm mounts must be brute strong when Mustang owners experienced catastrophic on-track failure. If you succeed in developing a mechanically sound conversion kit that bolts-in, it will sell like hotcakes for real big bux. I think the 4+3 and automatic owners will buy more than you can produce.


[Modified by Rick93Z07, 12:35 PM 9/28/2002]

Nathan Plemons

Really? That's strange. Just for grins, what about new? I've heard upwards of $6k for a ZF.

ninetyfivevette

Well, this is my inspriation.

http://home.earthlink.net/~rontyler/t56.html

Also take a look at this 4L80E conversion bracket:

http://bowtye8.tzo.com/hovmovies/pic...vette/con6.JPG

If there is enough meat in the existing tail housing of the T56 for some extra mounting holes, perhaps this type of adapter mount could be made simply instead of making an entire new housing.

I want to take this one step further by making a new tail housing. I think in the end, it would be the best soltion.

The T56 out of the F-body is 1.4 inches longer than the 4L60E, which means a custom drive shaft is required, adding to the list of "custom" work. I was hoping against hope that they would be the same length.

Also, the more I look, a DECENT T56 is still in the 1000-1500 range on EBay (I see ZF6s in the same range as well on Ebay).

Does anybody know where I can find detailed dimensioned drawings of various transmissions (T56, 4L60E, ZF6)? I want to see where on the tail housing the torque beam needs to go.

Mike


[Modified by ninetyfivevette, 8:54 PM 9/28/2002]

ZBRA

Then why do the A4 and M6 F-bodies have the same driveshaft? Every time I have put a T56 in the place of a 4L60E, I have reused the original driveshaft. They have the same GM part number.

ninetyfivevette

Because the A4 in the F-body and the A4 in the Y-body are different dimensionally.

I have the specs at work if you are interested.

Otherwise, just do a google search and you will find that the A4 is Corvette specific.

Mike