Main bolts

[series8217]

What does the factory service manual say about reusing main bolts? I have never heard for sure whether or not they are torque-to-yield.
For other bolts (head bolts, flywheel bolts) the Chilton's manual says they must be replaced. It doesn't say about main bolts, but the torque spec is pretty intense (37 ft lbs + 75 degrees if I remember correctly).
What's the deal on these? What does the GM manual say?

[SappySE107]

I don't reuse them. I am not 100%, but I thought that any bolt that has an angle after a torque spec makes it torque to yield.

[series8217]

I had been following that rule as well but I heard otherwise (i.e. that not all angle-torqued bolts are TTY) so I wasn't sure.
Do you have a factory service manual so you can see what GM says about the bolts?

[SappySE107]

There is no mention of them other than to follow the procedure for torque.

[series8217]

Apparently torque specs for the pushrod 60*s are like 70 ft lbs for main bolts but they're the same part number! Seems odd that GM would use regular bolts as TTY in another application.. but I guess thats what they're doing? 37 ft lbs + 75 degrees is certainly more than 70 ft lbs. Guess I'll order new ones.

[OldSkoolGP]

Crank main bolts shouldn't be tourque plus angle. IIRC, when I did mine the service manual said they were 32 ft lbs. The only time on a DOHc you should encounter torque plus angle specs is on the heads. I reused my crank main bolts, I have no problems.

[series8217]

32 ft lbs? No way dude. It's 70 ft-lbs on the pushrod motors, and 37 ft lbs + 75 degrees on the DOHC. Look it up..