Im looking for north of 500-550whp out of my new build. Its been around 10-12 years since my last build. I know there have been numerous drivetrain improvements since then and many different transmission options and adapters now. Im looking for the best option for street, occassional track and roadcourse. Im also looking for where to get the parts and what has worked and held up in real world testing and use. Any help is appreciated.

 

Tko

 

Really, no other info?

 

I would contact liberty transmissions about what they can do to strengthen the transmission of the rx7, I use a twin plate exedy sprung disc on mine, but I am not making the power you are planning to make. I think I am around 400-450WHP when I turn the boost up. mainly run the car in the 380WHP range most likely.

LIBERTYS MANUAL TRANSMISSION SERVICES

 

Honestly, with the cost of upgrading to another transmission, why not stay with the stock tranny and see if it holds up? 500-550rwhp seems like it should be okay on the street and probably for occasional track as long as you don't shock the hell out of the drivetrain

 

^ This! Now if you want proper gear spacing to keep your engine in its power band, a T-56 is your ticket. The fd tranny isn't close ratio enough for a 13b's narrow power band with your average large single turbo. I'll be fitting an m12 version of the T56 from a CTS-V in the summer.

Edit: Here's some T56 swap info.

https://www.rx7club.com/3rd-generati...500-hp-905977/

 

Best clutch for those power goals is the ACTZX6XTSS. Its a full faced disk that is smooth engaging and will easily hold the power. Otherwise you have to step up to a twin disk. The trans will be ok for a while at that power level but eventually you'll break it if you shift hard/launch often. Then you can start looking into something like OS Giken gear set, Liberty upgrades, or a full T56 swap.

 

Another vote for TKO500/600
QuickTime RM-4093 Bellhousing Mazda Rx7 13B/20B To Muncie/Jerico
And upgrade syncros WELCOME TO LIBERTYS HIGH PERFORMANCE
This is the route I'll go once I finish off my 4 TurboII trans I've got.

 

How much stronger is the OSG gear set? The exchange rate right now makes it very cheap around 1900. Tall first gear though though no real experience to know if that effects anything much at all.

Would be a nice option to keep the smooth shifting stock box and not worry about stripping 3rd gear out of it on the bigger power cars pending just how strong the setup actually is?

Jason

 

And just for the hell of it i broke down the gear/rpm differences between the two to see if there is a significant advantage or not.

Speed in gear is as follows based on a 25.7" tall tire and 8200rpm shift point:

OSG/USDM
60/44
86/75
119/110
153/153(stock 4th gear)

RPMs after each shift

1/2=5700/4750
2/3=5900/5600
3/4=6400/5900

Jason