[The Vandal]

492 heads, 1.55 pocket cut when I got them. It looks like a 1.55 pocket was cut first and then a smaller (1.28?) was cut and it is cut deeper (.04?). The pockets on the ends don't have much for the spring to sit on, maybe 50% diameter. Is this enough? Do I HAVE to run a cup under the springs? I've already bought my valves standard length and I may need all the valve height I can get - the cam is around .600 on the intake side. Will the difference in inner/outer spring installed height matter much?

Retainers/keepers/springs have NOT been purchased - please advise. I only want to buy them one time. Thanks,

The Vandal

[KULTULZ]

I would imagine they were cut that way for cups to keep hi-pressure springs from walking and possibly wearing into the head surface.

The springs are going to have to be shimmed regardless for proper tension/height...you just figure the thickness of the cups along with the shimming. Of course you will need to check for proper pushrod length.

If it turns out the valve stems are not tall enough, you just use lash caps to get you by it.

I would call COMP CAMS techline and speak to them before buying anything.

[BOBCRMAN@aol.com]

you will probably find that the 1.28 depth seat is factory it is common practice to use a .060 shim on the seat while cutting for big springs, this keeps the machinist out of hot water, literally, many of these castings can't take a full cut without weakening or breaking thru, many people just run the spring on what seat is available, you probably don't have room for spring seats , you made a mistake ordering the stock lenght valves, you may be able to use +.050 retainers and maybe +.050 locks to get the spring height you need but the longer valves would make things easier, don't forget you are going to have to use custom length pushrods and probably releived roller rockers to clear the taller retainers and locks.
>600 lift is way beyond the flow stock heads can handle.

[ March 26, 2003: Message edited by: BOBCRMAN@aol.com ]</p>

[The Vandal]

Thanks for the replys. The heads are FULLY ported but the .600 lift is on the exhaust - which is really the intake: I'm building a reverse-port. With a 1.60 intake valve I need a fair amount of lift (and whole lot of duration). Thanks again,

The Vandal