Has anyone ever tried to RE TAP the crank(hub) bolt hole? I know some of the forged cranks just crumble to peices when you try to tap new threads. My LT1 is in a 96 Fleetwood if it makes any difference.
Also , when engine is idleing down, it sometimes wants to stall out and it seems too surge, sometimes causing it too stall

 

I have only messed up one stock crank before, but yes we managed to tap it and run the threads on the bolt and it went back together. Damage was bad enough the bolt would not start to thread in by hand.

 

Try "chasing" the threads with a retapping tool before putting a sharp tap through them. If there is minor damage you could make things worse by using a sharp tap that cuts a new set of threads into the old ones. A thread chaser will tell you if you have enough left to hold without making things worse.

Good luck.

 

Also use cutting oil when chasing the threads; it does a good job lubricating.