[78w72]

Originally Posted by srmmmm

I used the Comp 1.5 roller rockers with their polylocks on 6X-4 heads with the factory rocker studs and a Comp XE276HR cam. My cast aluminum M/T valve covers were about 1/8" taller than the factory stamped metal covers and would not clear the polylocks, even with the 1/4" thick Butler gasket. I had to add Butler's spacer and another gasket for enough clearance.

Then the A/C compressor didn't clear the valve cover and I had to convert to a CVF serpentine belt drive. I wish I had known about the short polylocks. Those rockers wound up costing over $2000.

Wow, thats a lot of spacers! If youre running that big of a cam with poly locks you should consider changing to 7/16 studs... I had 1 factory bottleneck stud break with the xe268 FT cam, luckily the rocker arm & nut with the piece of stud in it just fell off to the side, I was close to home and limped it back with 1 valve being stuck closed.

I got these ARP studs for almost free so I will try to use them but for this engine stock SBC/BBC studs would be fine.