ok, i am in the process of building my engine and i had the Procharger 8 rib setup on the stock engine. I have a ATI hub/damper on my new engine and want to upgrade to a 12 rib system...I have the crank, blower and tensioner pulleys but am missing a think spacer that goes b/w the ATI damper and the 12 rib pulley....I know with the 8 rib setup, i have a thick aluminum spacer and 3 washer like spacers which gave me the correct offset...does anyone know how thick of a spacer i need to run the 12 rib without issues? Thank you in advance..

 

I had an 8 rib setup on a p600b. Went with the D1 head unit and bracket for 97SS Lt1, and, 12 rib pulley (7.6 - 3.4). I machined the huge alum spacer from my p600b set-up to fit between the neutral balance damper (from Jegs) and March Alt pulley. It was critical to machine a center pilot. Also, depth of spacer was measured relative to driven pulley on the head (measured with a straight edge). Hope this helps and good luck. (97SS 383 - D1)

 

I guess i could machine the one i have but i'd like to just buy one...

 

My experience... spacer is usually a custom piece. When you have your ATI mounted to the block, rotate the crank with 7.6 dia pulley hub and measure angular run-out relative to the straight-edge. Shim blower mounts to align/ square the drive and driven pulley face. I went to about 1/32 or less inches alignment. Also, I did alot of work on the ATI tensioner pulley (another story). Did not like how it worked. I'm always rippin into the car somewhere.

 

Think i'm gonna try the 8 rib setup with a smaller blower pulley, also it should be easier to shim the head unit out with washers to get the alignment on par. There aren't many machine shops in my area and i don't really know where to go and if the f up my 8 rib spacer than im screwed...lol

 

Call SDCE and they will make you a setup, stay with the 8rib and just upgrade to there tensioner and call it day. Thats what I did. Guys running 20+psi with the F1 and D1SC models.