For those of you that have vortec heads did you have the valve guides cut down or not? I've heard conflicting opinions on whether I need to do this or not also if I have to can I still use the rubber seals that came with the heads? I'm running a cam with .480 max lift too.

 

I would check the clearence. You may be OK or you may not be depending on production tolerences. You're right on the borderline.

 

I would definately check clearance as was suggested. I believe that the typical limit for the vortec heads is about .480 lift, also remember if you use 1.6 rockers that effects the total lift as well. I am not sure, but if you do have to get the guides cut down you may need to change seals as well, but again I am not sure.

 

Guides?

What kind of Vortec heads? I thought all Vortec heads were self-aligning. Did you get rid of the self-aligning rocker arms so you could use roller rockers?

 

The clearance issue is between the valve spring retainer and the valve guide boss.

I'm running .462/.469 lift on mine (compcams 262) with no mods or problems. And I've seen at least 4 or 5 people running the CompCams 268 with .477/.480 lift with stock Vortecs as well with no problems. But that is supposedly right on the borderline. I'd check it like suggested. I've *heard* some different retainers that are thinner/flater could cure this problem without modding the heads. Call up Compcams and ask them. They supposedly have a set of springs and retainers that will work, but I've only heard that through second hand sources. You need to talk to them. Let us know what they say BTW.

If you haven't purchased the Vortecs yet Scoggin Dickey sells some Vortecs pre-clearanced for higher lift cams along with better springs. They run under $600 last I saw...

------------------
Ray87Z
-Vortec headed 350.
86 IROC w/ a cammed 305 TPI.
Formerly Ray86IROC.
www.inter-scape.com/Ray


[This message has been edited by Ray87Z (edited July 07, 2001).]

 

I got by with the stock TPI cast heads with the ZZ4 cam without getting the guides cut by getting beefier springs (130#) on the seat and using +.050 installed height keepers and surface milling a couple thou's off the retainer bottoms.

There's ways around it, but it's not much fun when your rippin' studs out cause you didn't check (Take my advice as the man who did my heads up didn't check)