Head purchase dilemma...

[dougcw]

I have the Comp Cams 921 Spring Kit and am looking at buying heads now. The 921 kit is unused and still in the box. The problem is that most heads come already assembled with springs and retainers. From all of the specs it looks like you can't beat the 921s, so I was wondering if it is better to buy the heads already setup and essencially "throw away" the parts that come with the heads, or buy the CNC P/P Heads bare and get some valves and install them myself. I think the groove for the spring has to be cut slightly for the 921 too?

[Azrael]

IIRC 921s are Comps drop in dual springs for the LS1 heads, the 978's require some machining to the head to get the sping seats to sit properly. You could buy the parts seperately and depending on where you go you may actually save a buck. The other option is get some finished heads and replace the springs and sell the kit that came with the heads on here or on Ebay. There are people that are looking for springs for Cam swaps that would pick up a set of springs reasonably priced in a heartbeat. Or if they are good springs hold onto them until it is time to replace the 921's...

Shoot I rebuilt some AS Stage II heads with Patriot hardware (Gold spring kit, and bronze valve guides) and brand new Rev valves (2.02 in/ 1.575 ex) pretty cheaply. I found great deals on all brand new parts and put the heads together for around $300... Now I have a set of PRC Platinum duals with about 6k miles, a set of Comp 978's with 4k, and the brand new Patriots.

The 921s are great springs though, just overpriced IMHO. Good luck bro!