87GTR

iTrader: (61)

I know we all been talking about HP but in desiding for tranny I need to look at torq.

what kinda of ft# can be expected?


Thanks

Evil Aviator

It all depends on how you build it. Here are some examples:

Stock JC Cosmo - 280ps @ 6500rpm, 41.0kg-m @ 3000rpm (276bhp @ 6500rpm, 296 ft-lbs @ 3000rpm)

Pettit 20B w/ Stock Turbos & Street Port - 550bhp @ 7500rpm, 460ft-lbs @ 5500rpm

Atkins 20B w/ Single Turbo - 372bhp @ 6000rpm, 350ft-lbs @ 5000rpm

PFS 20B w/ T70 Single Turbo - 600bhp @ 7500rpm, 450ft-lbs @ 5000rpm

Chito's 20B w/ T64 Single Turbo - 457bhp @ 6500rpm, 434 ft-lbs @ 4750rpm

87GTR

iTrader: (61)

Evil thanks for the great info. looks like most of the modded cars are getting around 440~
I cant wait to get my car up and going.

Kurgan

So, Evil.... do you have the torque figures for a T-76 turbo on a cosmo 20b that has been ported? I'm assuming its going to be in the 500-550 area, but I'm not sure... Hopefully on the low side of that for my trannies sake

speaking of trannies... I'm VERY interested in this Guru Racing dog gear set that they are selling for our tranmissions... they run $4995, so they ain't too cheap, but if they do the job... who knows....

http://www.gurumotorsports.com/gearbox.html (I know there is a thread on this already, but I don't care!!!!)

Evil Aviator

No, I don't have any T-76 20B stats. I would think that the T-76 would have less low-end torque than the smaller T-series turbos because of the increased lag, but once all that boost kicks in you are going to get some major torque out of that thing.

Well, that's nice and all, but I can get a race-proven Jerico Road Race 5-speed for about the same price, and any NASCAR-watching SAE mechanic in the southeastern US can fix it. Personally, I'm tired of dealing with new untested products from the other side of the planet. Besides, the ratios in that Guru tranny are totally wrong for my car, although I'm sure that they will offer more ratios eventually.

Silex

Will any 6 speed trannys work with the 20b setup?

Kurgan

there is the HKS dogmission that has a 6-speed option, but that is $$$BANK$$$. Anything else is gonna be custom.

I know someone else makes a 6-speed for our cars... but I can't remember who... damnit!

IronMdnX

iTrader: (1)

I talked to G-Force a while back, if i remember right they sell an adaptor that fits their tranny and richmond 5&6 speeds(same bolt pattern). You need to get the 78-83 mustang 7.10 length input shaft and use the mustang disk. The transmision need some modifiation to clear the starter.

Silex

That sounds good. It's just that I was thinking that if you were going to put a bigger rotor in, you might as well change the tranny to something more delightful .

Node

iTrader: (1)

what about rear end and axles and whatnot. I mean, no one wants a domestic rear end if they can avoid it. Would stock (T2 or FD) work or would it just break on a good launch w/ slicks

Evil Aviator

As far as I know, the stock T2 rear has worked for those few people who have a streetable 20B FC. The thing is, you are never going to get traction with street tires, so that helps. I would imagine that a drag car would need a very strong live axle.

Dyre

How streetable would a 5/6 speed Dog box be on the street (assuming it had a H pattern shifter)? Im talking everyday driving to and from places, downshifting, etc...

How different must your driving style be? I assume you have to rev-match/heal-toe ever downshift.

Node

iTrader: (1)

here is a thread ( https://www.rx7club.com/forum/showth...threadid=50419 ) that talks all about dog boxs. It should answer any of your questions that you might have.

Dyre

Yeah i read through that thread when it came up the first time. Guess i just need to get behind the wheel of a car with a dog box before I'll really understand. Can't really get a feel for it in just words.