Valve stem height??
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From: Grayson, KY 41143
Valve stem height?? Okay picked up my heads yesterday from the local shop had some 2.02 intakes installed in an already ported set of 862 5.3 castings. They have a brand new machine that is a one swipe 3 angle valve job. None the less I get them home lastnight set them on the bench and notice that the tops of the valves are no longer uniform. Took a straight edge to the stems and all of the intakes read .032 lower. Called the shop this morning and they said their machine is setup to stock lengths for each individual set of heads they mill so they had to have been that way when I had brought them in. I guess my actual question is will this affect my pushrod length or rocker geometry? These heads were on another engine that I had with no problems just had stock valves in them at the time. I am planning on installing with comp 7.4 pushrods the heads have not been milled down at all still stock 61cc chambers. I just wish I would have noticed if there was a difference before I had the work done. Any suggestions..
Yes, it will. I would have this corrected otherwise you would probably have to run 2 different length pushrods at a minimum. I'm sure there are some out there who would run it like this, but I wouldn't. Just my $.02...
Shane
Shane
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From: Grayson, KY 41143
So in order to do that I would have to get .032 longer pushrods to run on the intake side? That should put my rocker wipe pattern right back where it should be. I just can't really imagine the stem heights being different when they came off the other engine never made a sound. Wouldn't that cause a tick or at least some noise in the valve terrain?
From the factory the tip heights are always within a couple thousanths. Anytime you alter valve diameter and/or the valve job, the seat height will be altered and therefore the valve tip will move up or down.
Shane
Shane
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From: Grayson, KY 41143
Well if that is the case then I have now made the exhaust stems .022 taller on top of the factory difference. Seems this is gonna make for a real odd ball length pushrod. Should 7.425 make up the difference? or 7.430-7.435 I am going to check my coil bind and what not tomorow evening this could be more problems than just stem height and pushrods
It's common for one of the valves to sink into the head more than the other. Normally you cut the tips of the valves to make them the same. Perhaps someone with more direct head porting experience will step in. I am only commenting on the heads that I personally have setup over the years.
Thanks,
Shane
Thanks,
Shane
