elior77

I'm looking for the best transmission upgrade, a gear set upgrade sound better then the kmiata swap... it is bolt on and all.

What are the pros and cons of this sets ?

Thanks
Elior

Reverant

iTrader: (10)

The Quaife gearset is not stronger than the stock gears, they just provide alternative ratios for stock power level cars.

elior77

I asked about 400-500hp engine

TNTUBA

iTrader: (1)

Good to know that the gearbox in my car that has lived behind a 400hp motor for 3 years of racing on 275 (now 295)mm wide slicks is no stronger than a stock 5 speed(That I killed 7 of in one season)

In Pro Solos we launch this thing at 5000 RPM and 21 PSI.

Most every issue I have seen with that gear-set is related to the instillation or build of the gearbox.

After 3 seasons I pulled mine apart for PM and found some spalling on the main shaft and lay shaft gears so I replaced them and the 2nd gear hub had some wear (I had forgotten that I reused an old used hub out of the donor box when I built it) so I ordered one of those from Mazda and threw new syncros in it and it's butter.

Reverant

iTrader: (10)

How much torque? Auto-X?

Savington

iTrader: (31)

https://www.miataturbo.net/build-threads-57/i-give-up-93051/

https://www.miataturbo.net/suspension-brakes-drivetrain-49/death-quaife-79417/

Plus a third non-public failure that I know of and can't discuss further.

I don't recommend Quaife 5sp boxes to my customers.

concealer404

iTrader: (3)

For your purposes:

Pros: None
Cons: All.

elior77

kmiata then ?

concealer404

iTrader: (3)

Readily available kit to swap on a transmission that is known to be stronger than what you have. Does this sound good or not?

elior77

I read the installation instruction... not a pretty sight...

concealer404

iTrader: (3)

True. Better install something that won't hold up to the power instead. At least it'll be easy, right?

elior77

Just making conversion no reason to jump all over me... but this is how you guyz like it - no ***** left for that.

concealer404

iTrader: (3)

Ok well what are the choices? I'm not sure what the question is anymore. Either make less power, or put a stronger transmission on it. Or just swap transmissions every couple weeks.

elior77

This is a discussion - I am discussing things.

I know the kmiata is a valid option - just trying to get some input on other solutions - any input on the osgiken gears ?

Thanks

concealer404

iTrader: (3)

Gears inside existing case will not keep together at your intended power levels. You need a different transmission.

Leafy

iTrader: (1)

So what you're saying is that in the amount of mileage of 5 track days you were another track day or two worth of mileage away from losing the main and layshaft gears to spalling. If the gears were spalling thats constant torque failure and not impact loading from the launches. Ricer math still put that as in the ballpark of 6 speed strength.

ryansmoneypit

iTrader: (6)

Has this car even been dyno'd ? Are we just chasing unicorns here? 500 hp....

sixshooter

iTrader: (12)

For the record, the shifter on the kmiata bmw swap feels as precise as operating a bolt action rifle. Its fantastic. See Tony Montana's build thread for pics of the installation.

KMiata

The reason we created the BMW trans kits is because there was demand for something other than a Miata trans in these cars. We weren't seeing people overall very satisfied with the Quaife gears.

E46 6-speed kits are about to drop, as well as our bolt-in Torsen mount for an easy PPF delete. So that will be another option to consider as well.

concealer404

iTrader: (3)

My body is ready.