Your opinion.....ring gap for n/a 434 sbc

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rewguy
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Your opinion.....ring gap for n/a 434 sbc

Post by rewguy » Thu Oct 11, 2018 11:05 pm

13 deg. 15-1, race gas, drag race, total seal ap top rings, Napier second. Std. Tension oil ring, vac pump.
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Mark O'Neal
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Re: Your opinion.....ring gap for n/a 434 sbc

Post by Mark O'Neal » Thu Oct 11, 2018 11:40 pm

.018 - .021

Or more.
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cjperformance
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Re: Your opinion.....ring gap for n/a 434 sbc

Post by cjperformance » Fri Oct 12, 2018 5:53 am

Piston material?
Block filler?
Target run temp?
More info.
Craig.
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Frankshaft
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Re: Your opinion.....ring gap for n/a 434 sbc

Post by Frankshaft » Fri Oct 12, 2018 8:00 am

I would set them at .024 and .030 2nd.
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rewguy
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Re: Your opinion.....ring gap for n/a 434 sbc

Post by rewguy » Fri Oct 12, 2018 9:07 am

2618 forged. Probably 175 degrees race temp. No block fill. Darr lil m block.
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engineguyBill
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Re: Your opinion.....ring gap for n/a 434 sbc

Post by engineguyBill » Fri Oct 12, 2018 10:16 am

.0045" to .0055" per inch of cylinder bore for the top ring; .0060" to .0070" for the second ring.
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steve316
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Re: Your opinion.....ring gap for n/a 434 sbc

Post by steve316 » Fri Oct 12, 2018 7:12 pm

I would go with mark's recommendations for the top ring and open up the second ring to .025
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steve316
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Re: Your opinion.....ring gap for n/a 434 sbc

Post by steve316 » Fri Oct 12, 2018 7:15 pm

Why are you running a standard tension expander with a vacuum pump?
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ProPower engines
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Re: Your opinion.....ring gap for n/a 434 sbc

Post by ProPower engines » Fri Oct 12, 2018 7:21 pm

rewguy wrote: ↑
Thu Oct 11, 2018 11:05 pm
 13 deg. 15-1, race gas, drag race, total seal ap top rings, Napier second. Std. Tension oil ring, vac pump.
Are the pistons gas ported in any way ???
And why a std. oil ring with a vac. pump?? Why no go with a low tension oil ring?? Issues with the combo before??
Real Race Cars Don't Have Doors
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rewguy
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Re: Your opinion.....ring gap for n/a 434 sbc

Post by rewguy » Fri Oct 12, 2018 10:01 pm

no reason. I just put back exactly what was in there.
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