crank pulley bolt pattern... diff between SBC and LT1??? - Third Generation F-Body Message Boards

MrDude_1 · 01-21-2004, 04:38 PM

is the bolt pattern for the crank pulley the same between a LT1 and a SBC?

im considering using a blower pulley ment for a LT1 to run my blower on my SBC.... i need to know if they will bolt together though...

biggtime · 01-21-2004, 05:30 PM

My procharger bottom pulley came with a big block center hole and the spacer adapted it. It was from a LT1 when I put it on my third gen. the new adapter did the same thing. the 3 bolts are on the same circle on all three of those engines. although they use different threads.

92Z · 01-21-2004, 10:33 PM

A non LT1 crank pulley (or harmonic balancer) is on a 3.2 dia. 3 bolt hole circle (120 degrees between the holes). The LT1 pattern has one hole offset 5 degrees. ATI slots one hole on their crank pullies to fit both the L98 and LT1. Don't know about Vortech or any other blower pulley manufactures.

MrDude_1 · 01-22-2004, 09:29 AM

Quote:

Originally posted by 92Z
A non LT1 crank pulley (or harmonic balancer) is on a 3.2 dia. 3 bolt hole circle (120 degrees between the holes). The LT1 pattern has one hole offset 5 degrees. ATI slots one hole on their crank pullies to fit both the L98 and LT1. Don't know about Vortech or any other blower pulley manufactures.

AAAAAhhhhhhhh! thats it!

thanks.

so now all i have to do is get one ment for a LT1, and possibly slot one hole a lil bit.... i can do that with a hand drill....

i dont have a lathe, otherwise, i wouldnt have this problem at all.

biggtime · 01-22-2004, 03:11 PM

I have a eight rib laying around, let me know