.25mm Crank wear, bad for boost?
 

Hello fellow Miata people. Need some guidance with my build as I have been getting mixed views.

I'm rebuilding my engine for a turbo build. My crank is at -.25mm. The mechanic tells me I should get a standard crank for my goals.

I personally find it hard to believe .025mm wear on a forged crank can possibly compromise it when using properly sized bearings. I've done some reasearch in general applications and found it was not something to worry about.

I'm hoping to get some knowledgeable feedback since, while I'm willing to make the purchase of a standard crank, I rather not spend money on parts that I don't really need especially when I already bought the bearings.

Thanks!

https://www.miataturbo.net/attachmen...ine=1448771257

Build details: 99 miata, 84mm CP PIstons, Eagle Rods, Cosmetic .060 Gasket, SS I/E valves, supertech light double springs, SUB lifters, ATI Damper, Billet gear oil pump and ARP hardware, MS2PnP. EFR planned for the summer.

I would seek out a standard crank.

Why are you using an .060" Cometic gasket?

So I landed my self a fair deal. Picked up a standard crank and engine block in exchange for my 1.8 flywheel and clutch, arp bolts and eagle rods. I'll only need to pickup a new set of rods. In the end I'm paying $350 for Crank and Block. Locally, that's a pretty good deal.

For what it's worth. I did get plenty of feedback from various Miata Groups that I was not a high risk to go with the worn crank. However, the safer the better.

https://www.miataturbo.net/attachmen...ine=1450291406