Valve to piston interference

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09-08-2009, 04:49 PM
motorcitymellowyellow

Valve to piston interference

First I really enjoy reading all of the post here :t:
Second I have a low compression stock 360 that I am considering changing the cam and heads.

Is there a certain point that I need to clay the piston and mock up the combination that I want to use. And then measure the clay. The cam is an Elgin # e9819 The valve lift is .520 and the exhaust is .544 the lobe centers are int. 107 and the exh.117 so it looks like the cam has 10 degrees of advance ground in it. So I would install it straight up and down.

Any advice you could give me would be greatly appreciated. =D>
09-08-2009, 06:14 PM
tufcj

Welcome to Bulltear!

At stock compression, you probably won't have any valve/piston interference unless you mill the heads quite a bit. With AMC heads, once you're over .500" lift, you need to look at coil bind on the valve spring, if the slot is long enough to give the rocker enough travel, and if there is interference between the valve guide, valve seal, and valve retainer. You will need some sort of a positive valve seal, as the factory umbrella style seals will get smashed.

That's a lot of cam for a low compression engine. Those specs would probably work better with something in the 10:1 area.

Bob
tufcj
09-08-2009, 06:16 PM
fifesjeep

Quote:

Originally Posted by tufcj

That's a lot of cam for a low compression engine. Those specs would probably work better with something in the 10:1 area.

Bob
tufcj

X2
09-08-2009, 06:41 PM
motorcitymellowyellow

Thank you for you input. The plan is to use this cam and heads on a 10 to 1 compression 401 for my Javelin. When I can afford to put the short block together. I will post some pictures when I can figure out how to upload them..

Thanks again