I am swapping an ls1 into my miata, (Build thread) and I won't have enough money to swap to an 8.8 immediately. So I was wondering if anyone had any experience with having differential parts cryo treated and shot peened for extra strength. I read this Motoiq article and it looks promising. Anyone know of places doing this in Vancouver Canada or close to there?
I'd sooner spend the money to put a spare diff on the shelf for when you inadvertently liquefy the first one. As the article mentions at the end, such things are more a reliability improvement for an already reasonably sized part holding up OK. In the meantime, fill it with 85w140 and don't run big sticky tires.
The plan is to swap to a 8.8 next year, so I'm only trying to stretch the life out for perhaps 3k miles. And I have 225/45/15 nitto n1s for it so tons of grip.
I dont think youll be doing much hooking with a 225 section width tire and a LS1 especially with any of the final drive the miatas came with.
No clutch dumps or axle hop and maybe you can make it survive a few k miles, or maybe it explodes then we all get to see some awesome carnage pics. I wouldnt waste money on freezing or shot peening.
"If you don't break traction, you'll break something else."
We know they survive behind Miatas at 400 rwhp+ without wheel hop and without cryo. Just don't drive like a maroon.
Traction is less of a problem than most of you guys think. +1 to Keith. It'll live just fine if you have a shred of mechanical empathy. Gearing is the worst part about keeping the Miata rear.
In reply to Keith Tanner:
Yes, drive like a crimson, not a maroon. 
I've never seen any evidence that cryo actually works. The treatment always seems to be marketed based on nothing but claims and testimonials, but without any metalurgical data analysis to back it up.
I have some knives that are ice hardened. I'd bet that the ice treating refines the crystal structure of the metal making it more uniform and the metal inherently stronger. I couldn't imagine this treatment turning a part into something it isn't though, probably would make a part marginally stronger but I always wonder about durability.
How much is cryo? That's be the "end all" to this conversation!
Keith Tanner wrote: We know they survive behind Miatas at 400 rwhp+ without wheel hop and without cryo. Just don't drive like a maroon.
I know plenty of guys running V-8 914s with the stock 901 transaxle, not known as a particularly robust piece. Just drive it with care and it will survive just fine
IMO the thing that kills the R&P is the housing distorting. The hypoid action of the gears tries to push the pinion forward and the diff carrier backward. When mesh goes akilter, the gears live a very short life.
One thing you can do to help, that I never looked into beyond the "neat idea" stage, is decent studs for the carrier caps. The caps have a silly low torque and I found that if you try to go much over spec torque, the bolts will fail. (Mainly because I had the wrong torque spec, I thought it was 80ft-lb for some reason, they fail around 50ft-lb)
In reply to benzbaronDaryn:
No, ice treating doesn't refine crystal structure. Heat is the only thing that can typically do that with metal. Homogenization, Hot Rolling, Annealing are all ways that affect the grain structure of the metal. Freezing, not so much.
What freezing does is help the transition from austenite to martensite in steels....although the literature out there is contradictory at best
Thanks for the clarification, maybe its just a jerk job, I think the knife I have seems to have a harder edge and keeps sharp a bit longer.
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