jkonkle

Hi everyone

Last year there was a big thread in this forum about timing chains being broken at Tracks throughout Texas. Here is an update.

The primary culprit is balance issues related directly to the crank pulleys/dampners.

In the stroker engines it seems like the underdrive's are too small to keep balence at HIGH RPMs

In a normalized engine with heads, cam, bore (no stroke) etc it would be related to the pulley's total balance regarding "in round." Think of the process of balencing your tires so they spin correctly and what happens when you don't; except this is on the crankshaft.

Basically, if you've got a stocker Corvette you should be fine, if you've modded and put on an underdrive, make sure the shop checked the balance. I'm running an ASP Underdrive and have had no issues!!

Later

JK

davidfarmer

GM worked with ATI to develop a propper underdrive pulley, and that is all I will run. They actually tested every rubber they make to find the one that worked best.

I run a 10% underdrive Aluminum ATI on all of my race engines.

I am also installing a JWIS timing chain.

jkonkle

Good suggestion; ultimately, even if you have ATI/ASP it might be worth checking the pulley's balance.

I'm not pointing fingers, just pointing to the pulley as an issue. At least two car's went through at least three timing chains (plus parts) before the pulley balance was identified.

JK