Lifter preload, pushrod sizing questions?
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From: Monroe LA
Lifter preload, pushrod sizing questions? I am getting some JPR stage 2 heads which are milled .030 to go with my MMS 224/224 cam. I am using crane cams stock replacement lifters(#10530). What size pushrod do I need? 7.35? Should I worry about lifter preload, and if so, what is necessary to be done.
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From: Evansville, IN
Re: Lifter preload, pushrod sizing questions? What's the size of the base circle on your cam? Is it stock? If so you will want to go with 7.35, if it is smaller, you might want to stay with stock size pushrods.
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From: SW Florida
Re: Lifter preload, pushrod sizing questions? One of the folks here measured his 224 CompCam with an inside caliper.
Stock LS1 Base Circle: 1.552” across the lobe = 0.776” centerline to heel
Comp Cams Base Circle: 1.492” across the lobe = 0.746” centerline to heel (thats .030” less than stock)
Conclusion: If your cam is anywhere close to this guys, [and] you have had the heads milled .030", your going to have the same lifter preload as it had when it was stock if you use the stock length 7.40" pushrods.
Ron,
Stock LS1 Base Circle: 1.552” across the lobe = 0.776” centerline to heel
Comp Cams Base Circle: 1.492” across the lobe = 0.746” centerline to heel (thats .030” less than stock)
Conclusion: If your cam is anywhere close to this guys, [and] you have had the heads milled .030", your going to have the same lifter preload as it had when it was stock if you use the stock length 7.40" pushrods.
Ron,
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From: Elon, NC
Re: Lifter preload, pushrod sizing questions? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 2000SILVERTA:
<strong>I dont know the BS of my cam. I will email MMS and comp cams asap.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">If you have a custom ground cam, good luck getting Compcams to tell you what the base circle is. I called them for mine and they couldn't tell me <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> <img border="0" alt="[fight]" title="" src="graemlins/gr_punch.gif" /> <img border="0" alt="[guns]" title="" src="graemlins/gr_guns.gif" /> <img border="0" alt="[Banging Head]" title="" src="graemlins/gr_banghead.gif" />
<strong>I dont know the BS of my cam. I will email MMS and comp cams asap.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">If you have a custom ground cam, good luck getting Compcams to tell you what the base circle is. I called them for mine and they couldn't tell me <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> <img border="0" alt="[fight]" title="" src="graemlins/gr_punch.gif" /> <img border="0" alt="[guns]" title="" src="graemlins/gr_guns.gif" /> <img border="0" alt="[Banging Head]" title="" src="graemlins/gr_banghead.gif" />
