I'm installing a gm performance parts intake manifold as well as the gm performance parts front cover plug that plugs the optispark hole in the timing cover. The gm front cover plug has a timing pointer on it but it only allows the use of 6.75" diameter or smaller vibration dampers. I bought a Summit SFI damper p/n SUM-C4265 which has the correct outer diameter, but I can only install it about 0.25" onto the crank snout before the back of the damper hits one of the front cover plug bolts.

Are the ATI or Jegs SFI dampers that are specifically made for LT1's 6.75" diameter or smaller? I figured they are the same diameter as stock which is too big.

Does anyone know of another SFI damper part number that works?

There's got to be someone somewhere that has successfully installed a carburetor and SFI damper on an LT1. Let me know. Thanks.

 

Well I'll answer my own question:

Looks like I'll have to use the ATI part number 917327.
A lot more expensive than the stock small block chevy sfi dampers but it looks like it's the only one on the planet that will fit.