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WPC Treatment 5 Speed

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I recently blew 3rd gear on my 05 obxt while tuning for the new turbo. I estimate it was making a little over 400 whp when it blew. It wasn't from a hard shift either it was fully in gear flooring it and then kaboom 3rd gear delete. I'm eventually going to put a 6 speed in the car but I don't have the money for that at the moment so while I saved up I figured I would repair my 5MT and see if it will get me by till I can swap a 6 speed into it.


The transmission has 180k miles on it and the last 20k have been aggressive with 320whp. Took it apart and everything was ok except 3rd gear obviously, but it didn't take any thing else out with it. So I sent out the 1-4 gears to get WPC treated to hopefully make them stronger.


I'm wondering if anyone here has experience with WPC treatment or shot peening and can attest to the strength increase. I have heard of some people running 460whp for years on a 5 speed so I'm thinking fatigue was probably a big part of the failure. So I'm hoping with the new 3 and 4 as well as WPC treating them it will hold up. Hopefully someone here can give me an idea of how much stronger the wpc treatment will make the parts.


Thanks, ill add some pictures of the carnage!4cade1f9004df8ad6a1c69294a678e9b.jpg41bb455f845d32cd84747a90706475b9.jpg


Sent from my SM-G770U1 using Tapatalk

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you probably got your money worth out of that transmission. ppg gears & bulletproof upgrades would help. the 6mt is a better upgrade. wrx 6mt can be had cheaply.


3rd gear is pretty strong but speed shifting will damage it. I waited a second after shifting and rolled on throttle rather than mashing it. If you are not keeping up on fluid changes, that's not helpful either.


motoiq is fascinated by wpc:




searching on google shows numerous happy customers. Fast miata racers out here use wpc for alot parts. flogging transmissions is miata thing...driving down a straight banging on the redline instead of shifting

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