Transmission options and opinions

[c_mart_28]

Hey guys, maybe even specifically Ed C,

Trying to be prepared for what the extra power from my new setup may do to my transmission, I'm now investigating my options with my T56. As of now, it is 100% stock internally with a 26 spline input shaft and a Spec stage 3+ clutch.

My new blower will likely have a bit peakier powerband and not quite so much initial torque. I'm guessing around 750rwhp and 700 ft lbs on e85 instead of the 683/718 I was making spinning my 2.3 Whipple to death.

I've seen a few built and faceplated T56's perform at the track and it's impressive..but at what cost? Does that basically throw out any true streetable credibility that the transmission has?

I feel like my transmission is fine for the time being but I know i'm pushing the outer limits of it's capabilities. Not to mention that I know I'm leaving ET on the table with it being in stock form.

Just trying to get a few opinions..

Thanks,
Casey

[MurderedSnake]

I would not get your T56 faceplated if you want to drive it on the street (have fun downshifting). If it was a track only car then maybe but I would just send it off and have it built up to viper specs so you don't have to worry about it.

[c_mart_28]

Anyone know the tr6060 limits off hand?

[AutoMods]

There is an oiling modification that sends oil to the front of the case that perhaps prevents failure on high horsepower t56 cars. Its kind of theory still but do a search on ls1tech . There is a few threads on ls1tech about people not liking the streetability of the faceplated trans and one guy said he really didn't think his shifting got much faster and went back for streetability.

It will be interesting to see how my t56 holds up the next few years. I don't have the low end boost or launching you have and with my car being lighter, hopefully it stays reliable. I'll be keeping an eye on yours.

I say just run it until it breaks, it may not break for a long time.

Maybe jesse will chime in with his thoughts on the one on his viper.

[Aircooled]

http://promotionpowertrain.com/

[Domestic Disturbance]

I think the tremec t56 magnums are rated to 750lb/ft. They have triple synchro's 1-3, and some other strong stuff carried over from the tr6060.

[slow ride]

I'd just freshen yours for now, run the heavy input shaft and add the pump to keep oil up front if you feel it might be a issue. You have done well with the stock stuff so it's hard to change that. I'd say run it, make sure to look into good oils that won't shear easy. If it fails down the road you could add stuff then, but it is a risk as broken pieces could (not for sure though) take out other good parts.

If you look at some of the newer t56 and 6060's they pump oil up to the front gear cluster. Now this won't help the mainshaft, etc, but should help with bearing/gear oiling under high g launch conditions and high temp oil, etc. Faceplating will only help with powershifting and not add any strength to the helical cut factory style gears load face.

I'd run a clutch that doesn't lock up hard as that also sends torque spikes through the drivetrain. I know you will run bias ply tires at the track so it might not be an issue for you in track trim, but DR's are hard on stuff at the track with a stick.

[Jappbox]

After My deal with my "built" T56 in the viper and blowing it apart with 750-800hp 2 tranny shops RPM and Gforce, say that a t56 will hold 700hp above that its time bomb. The Gforce Version they offer changes the input shaft so it wont snap. Alot of research went in to my 6060 Trans decision. a Stock 6060 shifts 100X better and will hold north of 1300 TQ. STOCK!

[slow ride]

Built transmissions offer little extra torque capacity over stock parts when they run the stock type gears. At the higher power levels the actual gear becomes the weak link. Shafts tend to break from launching shock, etc not overall load. Even though the 6060's tend to do much better on high torque apps they are rated within 200 ft lbs of a t56. High power stick cars are just hard on stuff when the car doesn't rev to the moon and ends up making as much tq as hp.

Sometimes old transmissions with gears that have been broken in with each other seem to fair better than fresh new gears that have not broken in and have high spots that put excess load on the gear surface and crack. One nice thing about t56's is parts avalibility and price. Some people seem to think it's easier to powershift the t56 type box over the 6060 also. 6060 will shift smoother and hold more tq, but get fubared from mishifting, etc just as easy or easier than a t56. Hard to say at your power level really.

[c_mart_28]

Well I really appreciate the input guys.

More or less I'll just kinda play it by ear and take what it gives me. I really can't say I've ever had any issues with it I'm just trying to keep myself from getting caught off guard I suppose. I guess time will tell.