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Old 03-10-2011, 08:59 AM
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Default valve float

i just got dynoed and at around 6500 i had some valve float. i am running harland sharp rockers which im thinking is my problem. would i be better off putting in some stock rockers or trying to shim up the springs in order to fix this? my cam in .623/.623 lift and i have patriot .650 lift springs
thanks

Last edited by ls1curt; 03-10-2011 at 04:21 PM.
Old 03-10-2011, 09:18 AM
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I think you would be better off putting some stock rockers on the car. We prefer to use stock rockers unless absolutely forced to go aftermarket because of a set of heads. The stock ones seem to be the best out that can keep up with the aggressive heads/cam setups people are using these days.
Old 03-10-2011, 09:32 AM
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Dont shim the springs with out checking for coil bind, Shimming will raise the pressure on the spring but will also tighten up the coils and cause the spring to crush
Old 03-10-2011, 09:42 AM
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ill try switching back to stock rockers then. thanks
Old 03-10-2011, 10:47 AM
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Originally Posted by ls1curt
ill try switching back to stock rockers then. thanks
Hmmm...are your HS rockers 1.7:1? If so, I'd leave 'em alone & look into pushrods. Further, even if you were to go w/ a heavier spring, if the pushrods are pole vaulting, the issue may not go away. There are a few write ups in here that expalin the effect of pushrod flex. A thicker walled pushrod may be the answer if pole vaulting push rods are the source of the valve float (idea being that a vaulting push rod applies a higher inertial load to the spring than a push rod that does not flex & then spring into the rocker).
Old 03-10-2011, 11:15 AM
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Swap back to stock and use a trunion kit...
Old 03-10-2011, 11:23 AM
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We have consistantly seen aftermarket rocker sets like these have valve float because they are heavy. If you want to do anything to the rockers put a set of stock ones on with the comp trunion kit like vengeance said, best way to go for a problem free valvetrain on a setup like this.
Old 03-10-2011, 12:52 PM
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the h.s. are 1.7 but i think that im going to try going back to stockers with the trunion upgrade on them and see if that solves the float
Old 03-10-2011, 02:47 PM
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Test your springs while you're at it
Old 03-10-2011, 04:22 PM
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my springs were all tested about 1k miles ago and were good. just ordered up the trunion upgrade too
Old 03-11-2011, 12:00 AM
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I am running H/S Rockers and have always been! I now have a smaller cam as in my sig, i had been running Patriot Gold due to originally running a TSP 231/237 cam which revved freely to 7k.

On changing to the smaller cam which was meant to rev to 6700, but it wouldn't go past 6200. I replaced springs with a new set of Patriots, still wouldn't go past 6200,

A year later after a broken timing chain & adding a 102 Fast intake & 102 TB it wouldn't rev past 5500!!!!!!

We tried a set of standed LS2 springs & what do you know, the valve float kinda issue was solved.

I fitted a set of PAC 1518s and now the engine revs to 6700 no worries.

I personally don't believe it's the H/S Rockers
Old 03-12-2011, 12:07 AM
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Aluminum rockers are "heavy @ the valve" compared to stock w/upgrade




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