Valvetrain Geometry Q's
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Valvetrain Geometry Q's Ok,
Search is down, we all know. So I couldn't find out what I am looking for....
My setup is stock rockers, Trex cam. stock AFR225s, .043 gasket, 7.37 pushrods....
Ok I get 3/4 turn from 0 lash to 22ft/lbs (good) But my wipe is towards the headers.... What do I need to do? shim the rockers?
Search is down, we all know. So I couldn't find out what I am looking for....
My setup is stock rockers, Trex cam. stock AFR225s, .043 gasket, 7.37 pushrods....
Ok I get 3/4 turn from 0 lash to 22ft/lbs (good) But my wipe is towards the headers.... What do I need to do? shim the rockers?
Last edited by mr2guru; Jan 23, 2006 at 08:32 PM.
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Ok did a little test... had some 7.4s laying around and tried them. It moved my wipe closer to the center of the valve but increase my preload to 1 full turn.
I am assuming I would need to shim my rockers .030 and run 7.4s?
I am assuming I would need to shim my rockers .030 and run 7.4s?
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Ok.... This is obviously MY thread haha... but here's what I tried....
Looking for measured shims... most places look at me like I've got three eyes. Found some stainless washers that fit the 8mm rocker arm bolt perfectly and are about as wide as the pedestal. They are all exactly .035 (had to root through about 40 to get 16 all exactly the same with my dial caliper. So anyway...put one under the pedestal and bolted one rocker arm on. With 7.4s and that .035 shim I got 1/2 turn on the preload and my wipe is just outside biased by a hair.
I would think this is about as good as it gets??? Or can I even shim the stock pedestal?
Looking for measured shims... most places look at me like I've got three eyes. Found some stainless washers that fit the 8mm rocker arm bolt perfectly and are about as wide as the pedestal. They are all exactly .035 (had to root through about 40 to get 16 all exactly the same with my dial caliper. So anyway...put one under the pedestal and bolted one rocker arm on. With 7.4s and that .035 shim I got 1/2 turn on the preload and my wipe is just outside biased by a hair.
I would think this is about as good as it gets??? Or can I even shim the stock pedestal?
Launching!
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From: longview, tx
Are you using check springs to check the wipe? I'm not too sure you'll get an accurate wipe with the normal valve spring in place. Like I said, I not positive about that but I seem to recall that most lifters won't stay fully pumped up to give accurate readings. I've yet to remove the valve covers off one of these engines but I've heard of people shimming the pedestals. Sounds feasible as long as the shim covers all of the area the pedestal comes into contact on the head. You don't want your rockers flexing around on something too small in area. I'm a millwright so I make lots of custom shims from stock all the time.
