70DusterDev

Has anyone here blown an engine because of a wristpin failure?

I just found out that my 750whp setup (shooting for over 800 this summer) only has the 8620 (.150 thick I think from what I could find) wrist pins. Now I'm a little worried about that. When I built the car I wasn't expecting to make this kind of power being my first turbo build and I got my rotating assembly used (new in the box from a friend) so here I am haha.

What have you made on stock wristpins?

G Atsma

Usually the piston fails way before the wristpin.

70DusterDev

That's whats always happened to me haha and that's what the shop told me, but I wanted to see if anyone had ever actually had a failure or if I dont need to worry.

70DusterDev

Guess that isn't too common

Dian

how exactly is your wrist pin oiled? this might be more important than wall thickness. actually i find it remarkable they survive so well without direct oil feed.

KCS

iTrader: (20)

I’ve seen it happen. I think the pins were .110” thick and not meant for a power adder application. I think a lot of “piston failures” can be attributed to the pin flexing or just not having enough clearance and getting stuck in the pin bore.

I think Wiseco recommends heavy wall pins on combos that are going to make over 700hp or so. I have seen engines do just fine with more than that and standard pins, so I know it’s not necessary, but still a good recommendation.

70DusterDev

Yeah, if I ever have the motor apart, it'll get upgraded pins for sure. For now, go till she blows I suppose. Its mostly a street car with a few trips to the strip here and there so it doesn't see quite the same hammering a dedicated drag car or drift car will.