Do I need to replace them when I change to a lighter flywheel? Or just use lock tight and torque to spec?
^^ yup. the flywheel bolts are what is called "torque to yield" which basically means only should be used once because when you torque them the first time they stretch out.
a popular upgrade is doing arp bolts. really, they are about the same price as the new GM one's. hit up the transmission forum for more details and these.
M45/OS crank/2.4 snout. It's nice to be injected but I love being blown!
Yup, wish I had gone ARP when I swapped motors this past fall, but I was in a rush gathering parts to get it running and overlooked it. Like Brad said, not much more money than oem bolts. I'll definitely be going ARP when it comes time to upgrade clutch and flywheel
New bolts with thread locker.
If you go ARP be mindful that their torque specs are different than stock.
Slowly but surely may some day win this race...
Would the new flywheel being aluminum require a different torque spec the stock?
yes it would
JBO since July 30, 2001
and what would that torque be?
My flywheel instructions specifically said- follow factory torque specs. And I've never replaced flywheel bolts after three different flywheels. Technically, I should have, since yes, they are torque to yield, but the car god has granted me long life and plentiful bounty.