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<div dir="ltr" data-setdir="false"><span><span>Steve nailed it, both on the ##s, & the importance of it.</span></span></div><div dir="ltr" data-setdir="false">It depends on what rods & crank, piston to wall clearance & what RPM, but for most applications that's right in the ballpark.<br></div><div dir="ltr" data-setdir="false">I've run as little as oops not enough ie .025 or less, .028 minimum (you won't get any carbon deposit on the squish area), but to play it safe nowadays I use .030-.032</div><div dir="ltr" data-setdir="false"><div><span><div dir="ltr" data-setdir="false">Also on these engines it's not only a CR related issue, the squish is very critical, you want to minimize the clearance between piston top & head to maximize the squish effect, which creates turbulence, which assists in good combustion...<br></div></span><div><span><div dir="ltr" data-setdir="false"><br></div></span><div><span><div dir="ltr" data-setdir="false">Glen Efinger.</div></span></div></div></div><div><br></div></div><div><br></div>
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On Thursday, January 11, 2024 at 01:00:50 PM EST, Steven Belfer via Fot <fot@autox.team.net> wrote:
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<div><div dir="ltr">You want as little as necessary because this is where your high CR comes from. The thickness of the head gasket is the major part of P to H clearance. I ran .026 P to H clearance at Cal Speedway and the piston kissed the head and I spun a bearing. My machine shop guy likes .040 for safety but I’ve been running .032 and it’s working out great<br clear="none">~Steve<br clear="none"><br clear="none"><br clear="none">> On Jan 11, 2024, at 9:13 AM, Lorne Fritz via Fot <<a shape="rect" href="mailto:fot@autox.team.net" rel="nofollow" target="_blank">fot@autox.team.net</a>> wrote:<br clear="none">> <br clear="none">> <br clear="none">> Hi. In the past I have had pistons hit the head and leave a mark(TR3/4). What piston to head clearance are most of you running? Thanks in advance, Lorne<br clear="none">> _______________________________________________<br clear="none">> <a shape="rect" href="mailto:fot@autox.team.net" rel="nofollow" target="_blank">fot@autox.team.net</a><br clear="none">> <br clear="none">> <a shape="rect" href="http://www.fot-racing.com" rel="nofollow" target="_blank">http://www.fot-racing.com</a><br clear="none">> <br clear="none">> Donate: <a shape="rect" href="http://www.team.net/donate.html" rel="nofollow" target="_blank">http://www.team.net/donate.html</a><br clear="none">> Archive: <a shape="rect" href="http://autox.team.net/archive" rel="nofollow" target="_blank">http://autox.team.net/archive</a> <a shape="rect" href="http://www.team.net/pipermail/fot" rel="nofollow" target="_blank">http://www.team.net/pipermail/fot</a><br clear="none">> Unsubscribe/Manage: <a shape="rect" href="http://autox.team.net/mailman/options/fot/steve@artwithcars.com" rel="nofollow" target="_blank">http://autox.team.net/mailman/options/fot/steve@artwithcars.com</a><div class="ydpeb00682yqt6848176626" id="ydpeb00682yqtfd30826"><br clear="none">> <br clear="none">> <br clear="none">_______________________________________________<br clear="none"><a shape="rect" href="mailto:fot@autox.team.net" rel="nofollow" target="_blank">fot@autox.team.net</a><br clear="none"><br clear="none"><a shape="rect" href="http://www.fot-racing.com" rel="nofollow" target="_blank">http://www.fot-racing.com</a><br clear="none"><br clear="none">Donate: <a shape="rect" href="http://www.team.net/donate.html" rel="nofollow" target="_blank">http://www.team.net/donate.html</a><br clear="none">Archive: <a shape="rect" href="http://autox.team.net/archive" rel="nofollow" target="_blank">http://autox.team.net/archive</a> <a shape="rect" href="http://www.team.net/pipermail/fot" rel="nofollow" target="_blank">http://www.team.net/pipermail/fot</a><br clear="none">Unsubscribe/Manage: <a shape="rect" href="http://autox.team.net/mailman/options/fot/fubog1@aol.com" rel="nofollow" target="_blank">http://autox.team.net/mailman/options/fot/fubog1@aol.com</a><br clear="none"><br clear="none"><br clear="none"></div></div></div>
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