Ill admit I don't know much about transmissions, That's why I was asking for help But i can assure you I will be putting 800+ to the floor, I'm not here to waste anyone's time, and i really do appreciate everyone's advice and help that was given. So maybe next time you post something stupid and disrespectful for no apparent reason you should give it some "REAL THOUGHT" thanks.

 

That's asking a LOT from ANY tranny.
Was reading an article today on the Hennessy Camaro with a 725 hp 'Vette engine in it, and the Tremec 6 speed was just suffering tremendous clutch slip. Although I guess that is more of a clutch issue than a transmission....

 

My friend has a 6.0 GTO and his gears seem so short, especially 2nd... My only fear would be to have shorter gears then whats in the car already, aside from that i wouldn't mind a 6 speed. Do you happen to know If the t56 would hold up with its stock internals? Or will I have to build it up for more power capacity? Thank you.


P.S. This is the launch im dreaming for......


http://www.youtube.com/watch?v=HZ3HTrQ-WEo

 

Only crap I don't like to encourage is discouragment.

 

+1

http://www.youtube.com/watch?v=uVg0nAUuvB4

 

that's ernieT's car, thats why they told you to talk to him lol.. besides, i think that he was using the stock tranny at the time, and just only took a few passes each.

i think maybe a built gforce or liberty t5, or t56 will suite you well.

and p.s. the build looks sick! any more info?

 

First of all there are only a handful of 800 hp dynos to look at and so my calculations are based upon Ernie Ts results. I would assume looking at ErnieTs dynos that your motor will need to produce 550 lbs of torque or so to the wheels in a 800 hp 13b. This will be dependent on your porting as well. ErnieT has a bridge ported motor...I do not know what you are running. He was also running a 42r but he changes turbos like I change underwear. You are running a larger and therefore slower spooling turbo which will be easier on your trans and will produce torque more gradually.

I am no expert on the t56 transmission. Popular Hotrodding seems to think that the weaker non-viper t56s can hold 750 hp. Viper t56s are stronger and the mechanical differences between the two are described in the article below.

http://www.popularhotrodding.com/tec...ion/index.html

An LS motor making 750 hp is making over 600 lbs of torque and is not making it as progressively as your large turbo 13b.

You can always change the final drive of your car. If you are planning on making 800 hp I am sure you are going to be completely redoing the rear end of the car. If not I think you should reconsider especially if you are going to be draging the car on slicks. There are many t56 gear calculators out there for you to fiddle with. Keep in mind that you also will have an ~8000 rpm redline as opposed to the ~7000 or so for an LS1 motor.

If changing the final drive is not enough there are many companies that build t56 transmissions and can put custom ratios into your t56.

 

sounds good, Thanks for the info! and yes im running a bridgeport done by Kilo racing here in Florida

 

And him running his car requires me to change my underwear. I've never seen that launch vid before. OMG.

btw importfever, you see my turbo build thread? :-D Not hijacking, you just enabled me to dive into the single turbo world.

It seems i search the forum for an issue i have, and you posted the same issue a year and a half ago haha. history repeats itself.

Ill keep tabs on this thread, when i end up going gtx45 or what not haha. exciting. You will have to capture video on your launches. Something's gonna break, and i bet it will be entertaining

 

I can speak from experience, he had the GT35r setup. I have it now :-P And his engine bay was disgustingly gorgeous. So at least i can vouch for half of his sig haha

 

800hp is a lot

 

OP- +1 on the T56, it may be the cheapest, most readily available and easy to get worked on tranny that will hold the kinda power you are wanting to put down. To restate what flyweight said, also remember your rotary will not be putting down the same torque as those big V8's that typically run those tranny's.

On a secend note, that is a nice engine bay, but please tell me you will be upgrading to a nice dual oil cooler setup during this build too.

 

Im not sure yet about the oil cooler, Since its a quarter mile car the oil cooler is only gonna get hit with that much air from start line to finish so im not sure if a dual set up is really necessary..... but i have considered a nicer single aluminum oil cooler but it would probly be done in the future. Yea the T56 does sound like it out weighs all the other options so as of now it seems that's what im going to end up using. Thanks for your help.