Hi
Yesterday I stripped 4th gear while I was dynoing the car. This is second time I stripped the teeth on very short time.
First time I thought fair enough since I have been abused it with 500+whp/600+nm for a long time, without taking it apart and shimming it. (conical bearings)
Bought a used, good working tranny, took it apart and shimmed it. Reinstalled and everything good till yesterday when I stripped the teeth.
As what I have found out, it is not possible to buy a stronger 4th gear, only complete dogbox gearset from ie Magnus Motorsports and other.
Will a cryo treatment make my 4th gear stronger or is it just waste of time and money?
Other suggestions?
Currently makes 545whp/665nm.

Thanks

 

I think you should try asking on lancerregister. UK has had Evo's since then, doubt there's many (or any for that matter) people with experience on 500WHP and Evo 2's.

Edit: Cryo treatment however makes parts stronger indeed.

 

From what I have heard.. Cyro treating doesn't do much.. It might help a little bit.. but I think it is worth it to pay extra for Shot Peaning.. That's of course if the transmission shop has the expensive machine.. I know TRE (Team Rip Engineering) does. Good luck

 

is it a 2L or stroker motor?

 

2.3 stroker 4G63 short block.

 

sounds like the input shaft and the counter shaft are either pulling apart in the casting or it was shimmed loosely when assembled, some other manufacturers have similar issues so after market companies make a cuff that eliminates 5th gear and keeps the shafts from shifting apart. the shifting apart decreases the contact patch and that causes the shearing of the teeth. maybe you can have something like this made, or you can possibly reinforce the casing

 

I'd try talking to a reputable Evo trans shop and see what they advise.

 

sheptrans is thinking about making a new 4th gear and shaft that are both stronger and the 4th gear is removable. talk to him as the more people interested in this the more likley he will get it made.(I'm going to need one too)

Let me know what he says. been a month or so since I have heard anything;-)

 

Shoot peening would help. Look at the Team Rip Engineering (teamrip.com) web page for more details.