T56 Install

so the swap is pretty easy using a mix of factory parts.

I feel like I should be building another 2.5 TII Shelby Charger using spirit and shadow parts, haha.

Does the tailshaft come out seperate without problem from the main section? I think its the T-45s that the bellhouseing is part of everything and will cause problems if seperated, is this the case?
 
There is no separate tailshaft on the T56. The mainshaft runs the length of the tranny, the back part of the mainshaft *is* the tailshaft.
The bell is not cast as part of the transmission case - take a closer look at the pictures above or go to Tremec's website and download the tranny service guide pdf. In a T56 the bell bolts to the mid (adapter) plate, the tranny case bolts to the other side of the adapter plate and the tailhousing bolts to the main case.
 
Here is a comparison of the different gear ratios with rpm points after shifting. Calculations assume torque peak as shown as well as top RPM. This is with a stock tire wheel dimensions and 3.08 gears. If you want to see shift RPM recommended as well I'll do it again. Just takes a while to run the numbers and cut and paste stuff.

I'm thinking the F-body matches up fairly well if you want to keep shift RPM reasonable. where are the MPX cars running out of power? Above 5200? If you think your car will keep making power up to 6k.. then the GTO one looks like a nice option. F-body also looks like it'll hold 3rd for the 1/4 mile based on MPH.

give me peak RPM and torque peak rpm with gears and tires and I can run some different numbers.
 

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Attached to this post is a spreadsheet you can play with. It shows the MPH in each gear for a given RPM, rear ratio and tire height. You can then change the rpm or tire height or rear gear and see how that will impact the MPH achieved at the rpm.
 

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Thats a great spreadsheet, the only problem I find is that the final ratio is not individual from the 4 different gear boxes. The FBody ratios seem to be too mild for a 3.08 in comparison to the stock trannys. Not sure if there is a way adding different rear end ratios to each scenario.

So you thoughts are that the FBody is the better choice because the ratios are evenly spaced for the most part. The Fbody trans will be come more abundant then the GTO. The Fbody guys like to upgrade to GTO box due to its improvements, The syncros and Forks are much better in the GTO, among other improvements. Because of this they are rarer and more in demand then the Fbody ones. To me it seems that the FBOdy ones are plenty strong to what our car can give them so Gear ratios are more important to me. then the improvements. If the FBody is the better choice with the right rear end then I would not think twice since they are cheaper and more available then the GTO ones.
 
Thats a great spreadsheet, the only problem I find is that the final ratio is not individual from the 4 different gear boxes. The FBody ratios seem to be too mild for a 3.08 in comparison to the stock trannys. Not sure if there is a way adding different rear end ratios to each scenario.

Attached has the rear gear broken out into one for each transmission ratio range.

I feel like I like the F-Body unit just for the longer overdrive. I'd like to do some high speed runs in the future, and that will give me some legs without having to change gears from what I can use on the street.
 

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Yes, after much calculations and deliberations I think that the, Fbody ratios in front of a 3.73 rear end is the best combination. IMO

With that set up First gear is almost just like an Early M5R2 with 2.73s, and that means a near perfect launch gear. Third and fourth gear is almost like having our stock one with 3.27s witch was very fun in those gears. And if revving the car to 6000rpms it is possible to finish the 1/4mile in third. And last the car will cruise in 6th at 75mph only at 1800RPMs. And that should give good gas mileage. Also torque rating increase with the 2.66 first gear.

Another note is that chevy went back to the 2.66 ratios for the Z06 on the later C6s and CTS-V also stepped down to the 2.66 ratios.

But if you find a GTO box it would be best with 3.55s in the rear end and nothing higher.
D&D also has no problem finding F-body boxes but they have no GTO boxes. So when I do it I think I will go with the Fbody box.
 
I don't know where these ideas come from. Stock LT1's made over 300ftlbs torque. The transmissions being referred to here might not stand up to 5500rpm clutch dumps, but neither will your axles. I would have no reservations about putting one in my car. They are stronger than an M5R2.

Agreed. My '02 Z28 convertible t56 is still 70mph chirping 3rd with 104,000 miles on it :rock: The t56 is plenty strong. Of course the SC is about 400lbs heavier, but not too bad.

Oh, by the way, driving this car three years and 55k miles...before that, my 94 SC auto for seven years and 114k miles. Ever since my Z, I always figured it'd be killer to do the SC right, and yes, swap in the t56, but damn, leave the LS1 attached, these things rock like you need to experience. An SC would be like BatPimp or something.....
 
MikeH
Something that I forgot to bring up. You are using the stock flywheel which then you have to use the stock starter for it to work. Will that FordSmallBlock adapter bell accept the 3.8l starter or will you have to rethink and use a 5.0L flywheel and starter. I am not sure if the starters are the similar bolting pattern and only the gear teeth count is different.
 
Attached to this post is a spreadsheet you can play with. It shows the MPH in each gear for a given RPM, rear ratio and tire height. You can then change the rpm or tire height or rear gear and see how that will impact the MPH achieved at the rpm.

Its looking like 3.73 FTW.
 
done 'til spring

Well, out of town till spring for work. Reassembly of motor will have to wait until I get back home.
Initial fitup starter seemed to fit, but will check on final assy.

MikeH
 
turning into winter project.....

Hurt my back a few weeks ago. Trying to get my son to help me out this fall, now that his schedule has steadied out. Have to pull the motor out of my auto to transplant into the 6 speed. Install another brace on the trans x-member, and new driveshaft.
Then we shall see what we see.
MikeH
 
This thread seems to have the most info about this swap. After this weekends trip, I maybe also looking at this swap into my 95 SC. The donor car is a 1996 Z28 Camaro, the owner had a bad accident with the car. Both my brother in law & I are tring to grab some parts off of him for our seperate projects.
 
Ryan, if you can get the trans crossmember, don't know if it can be adapted. The LS1 trans mount sits farther back than a M5R2, and 6th gear eats alot of the depth out of the SC crossmember when modified. I welded an extension for the tailshaft mount (GM unit), now am fabbing up a '3rd leg' for the crossmember and a mounting pad that will be welded to the floor pan. I still think one of the most critical points is input shaft alignment, slave and clutch shimming. I am using a McLeod LS1/Ford bellhousing) adapter, with Ford oem slave (reamed out to slip over GM input shaft).
Good Luck, and keep us posted.
MikeH
 
I would be able to get the stock cross member from the Camaro, but I do have the ability to make up almost anything. I am a machinist by trade & work in a custom fabrication shop. With this posts info, I now have a good idea of what extra parts are needed aside from the transmission. I would want to run the gears I have now, 3.27's. I wonder how many 94 or 95's have gone this route? I plan on, if I do go threw with this, to document as much as possible with photos & if possible with my video camera. I'll also keep drawings on the custom parts, so they could made up again ,for the next guys.......;)
 
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