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Update: Valvetrain and Lash Caps

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Old Dec 21, 2009 | 05:01 PM
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Default Update: Valvetrain and Lash Caps

As an update to my post a few days ago.
http://forums.corvetteforum.com/c3-t...n-experts.html

I got the lash caps and mocked up the valvetrain again to check the pushrod length and conatct pattern on the valve. Now the caps are .080 thick so I figured I would need at least .050 longer pushrods. Mocked it up and the checker told me I needed a pushrod .060 longer. Before the caps it told me I needed about .045 longer. It looks like it does not go hand it hand as the valve gets longer the pushrod needs to go longer at the same rate. Anyway here is my latest contact pattern with the same pushrods as before. Looks pretty good. The picture is not as good due the the caps being a darker color than the valve tips. Also a picture of the cap on the valve tip. Some suggested be careful the cap does not rest on the valve keeper. As you can see it is not close at all. The caps are right from AFR. I now need to shim the springs to the correct height for the correct spring pressure. I just need to order them. Not a good local speed shop around here. It looks good here. I'll run it like this.



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Old Dec 21, 2009 | 05:11 PM
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Looks good, I run lash caps with solid roller cams until AFR came out with odd sized valve stem diameters that didn't fit the lash caps I bought from Comp so I don't have the lash caps on my 427ci
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Old Dec 21, 2009 | 05:15 PM
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These are the 8mm valve stems. AFR had the correct lash caps in stock. Sent them right out to me.
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Old Dec 21, 2009 | 05:19 PM
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It looks like your contact pattern on the intake valve is off center to the left - you might want to recheck your guide plate alignment.
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Old Dec 21, 2009 | 05:23 PM
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That looks good to me! I had an engine that the underside of the roller tip CC 1.6 RR's were touching the edge of the spring retainers. Lash caps were the answer to extending the valve stem tip for additional clearance.
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Old Dec 21, 2009 | 07:39 PM
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Originally Posted by larrywalk
It looks like your contact pattern on the intake valve is off center to the left - you might want to recheck your guide plate alignment.
Yes you are right. I have not touched the guide plates yet. Once I get the springs all set up I will adjust the guide plates.
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