306 cam, anybody remember valve spring height?
07-11-2010, 10:41 PM
#3
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It seems everywhere I read, like on lunati and comp cams website to install the valve springs at the cam cards recommendation.
From lunati's website:
Check the distance against what is recommended on the camshaft specification card. An installed height of +/- 0.020" is acceptable.
From lunati's website:
Check the distance against what is recommended on the camshaft specification card. An installed height of +/- 0.020" is acceptable.
07-11-2010, 11:00 PM
#4
Installed height is something YOU need to measure on each spring. Like I said in your other thread, those crane springs have enough rate for what you're trying to do with the cc306, I'd set the springs up with a good .040 to coilbind, which crane has listed at 1.080.
1.080 + .040 + .610 = ~1.730
That makes the pressures a little stiff, move it to 1.75 and you get something like 168/406 on a new spring, figure a few percent loss after a few heat cycles and you're at ~160/385 which will be fine. Those numbers are based on a .612 net lift, which really will be less than .600 when you figure in the pushrods and rockers flexing.
1.080 + .040 + .610 = ~1.730
That makes the pressures a little stiff, move it to 1.75 and you get something like 168/406 on a new spring, figure a few percent loss after a few heat cycles and you're at ~160/385 which will be fine. Those numbers are based on a .612 net lift, which really will be less than .600 when you figure in the pushrods and rockers flexing.
07-12-2010, 06:10 AM
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Installed height is something YOU need to measure on each spring. Like I said in your other thread, those crane springs have enough rate for what you're trying to do with the cc306, I'd set the springs up with a good .040 to coilbind, which crane has listed at 1.080.
1.080 + .040 + .610 = ~1.730
That makes the pressures a little stiff, move it to 1.75 and you get something like 168/406 on a new spring, figure a few percent loss after a few heat cycles and you're at ~160/385 which will be fine. Those numbers are based on a .612 net lift, which really will be less than .600 when you figure in the pushrods and rockers flexing.
1.080 + .040 + .610 = ~1.730
That makes the pressures a little stiff, move it to 1.75 and you get something like 168/406 on a new spring, figure a few percent loss after a few heat cycles and you're at ~160/385 which will be fine. Those numbers are based on a .612 net lift, which really will be less than .600 when you figure in the pushrods and rockers flexing.
07-12-2010, 01:59 PM
#6
Hey I don't want you thinking I wasn't listening. I just thought they still needed to be installed within a certain range based on the cam. It least that is what these cam companies are making it look like. So again yes I am going to measure the springs on the head. I was just wanting to see how close they were to the cams recommended install height. I guess that is not a big deal though. Anyhow thanks man.
