boosteds10

What is the difference between the t56 in the camaro/firbird and the mn12 in the gto/vette/cts-v?

SS4Luck

iTrader: (10)

ratios are the big difference i believe

thesource

iTrader: (60)

Gear ratio, syncro design and shift selector in the rear housing.

TDP

iTrader: (23)

Mn12 has triple cone rings, & lower gear ratios (1st is 2.97 vs 2.66 in the M6, etc)

ponjohn

Is the MN12 the trans of choice if transplanting an LS ?

Is first gear the only gear ratio that is different from the T56?

sixty4sedan

iTrader: (3)

Is there a difference in bellhousings as well?

And from what Ive read so far are stronger than the f body due to the syncros and same gearing as the z06

01ssreda4

iTrader: (96)

I believe 1st, 2nd, and 3rd are steeper, with 2nd being the biggest difference from the f-body trans. 4th is still 1:1 and 5th and 6th ODs are the same.

squee

iTrader: (16)

Wrong, and wrong...

2nd for the f-body is 1.78 vs. 2.07 for a total difference of .29
1st for the f-body is 2.66 vs. 2.97 for a total difference of .31
Thus first is the biggest difference.

5th is .84 vs. .74, 6th is .57 vs. .50, and even reverse is different at 3.28 vs. 2.90. The only one thats the same is 4th a 1:1, and that goes for all T56s.

01ssreda4

iTrader: (96)

Well thats good to have that clarified. Perhaps the MN12 owner I know is misinformed.

squee

iTrader: (16)

Everything you could possibly need to know about all GM T56 variants.

http://www.eecis.udel.edu/~davis/z28..._Fbody_T56.pdf

boosteds10

In your opinion what would be the best for my 5.3 turbo swap in my 2wd s10 (5-550rwhp)?

jmd

iTrader: (4)

For e.t. and given it's 2WD, an automatic.

boosteds10

its not being built for the track. Thats not to say it wont see it from time to time

jmd

iTrader: (4)

?

boosteds10

Well i guess that would be helpful to know now wouldnt it? LOL
Its beeing built for the street(weekend sunny days and the occassional "spirited drive") and it might see the track 5 or 6 times and year when its done.

ponjohn

Great write up.

Does M12 = MN12 in that article?

squee

iTrader: (16)

If you look towards the bottom, you'll see it explains everything regarding that and the different names and such of all the gear sets. F-body would M28 and M29 for 93 cars, and MM6 for all the others for example. M10 is the SSR, etc. It gets a little confusing, but basically, yes.

ponjohn

I'll read it again when I am bright eyed and bushy tailed.

squee

iTrader: (16)

Honestly, its hard to say depending stuff like your rear end gears and such, but your best bet is to built with various parts. I'd use something like the MM6 gear set (all the others first gear is entirely TOO low), go with the SSR output shaft (biggest available; 32 spline and uses a TH400 yoke), and then the tripple cone 1/2 syncros, and the double cone 3/4 and 5/6 syncros from pretty much ANY T56 other than the F-body (GTO, later model Vettes, CTS-V, SSR, etc.), then go with a 1 piece counter shaft, and then the usual carbon blocker rings, billet keys, bronze pads, steel shift fork, etc. Problems with a setup like that is you pretty much have to have 2 trannys, or 1 and buy a bunch of different parts and some machining would be required, but to do that, you have to get the right tranny to start with, since some of the parts aren't available any more I don't think, like the SSR main shaft. Thats the best way to go, but it all really depends on your budget. That could cost $2500 or so if you built it yourself. It'll be bulletproof though, and it'll be good for around 8k RPM. The problem with the f-body double/single cone syncro setup is there really only good for about 6500 RPM vs. 8000 RPM or so for the tripple/double setup, that'll also give you smoother shifts and such.