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.

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.

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

Post by induction apprentice » Fri Oct 19, 2018 6:10 pm

Top .027"

Second .030"

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

Post by af2 » Fri Oct 19, 2018 7:06 pm

rewguy wrote:
Fri Oct 12, 2018 10:01 pm
no reason. I just put back exactly what was in there.
Then run it the way you did.
Why people set them at the closest they will ring butt is beyond me!
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Re: Your opinion.....ring gap for n/a 434 sbc

Post by In-Tech » Sun Oct 21, 2018 4:00 am

I'm with ya Adam, there isn't enough TIME, at any kind of reasonable racing rpm,for a couple thou extra to make a difference, gap within reason and put extra safety to it if you are worried about having to chase your tune.

Then put a vacuum pump on it and fuggit 'bout it. :lol:
Heat is energy, energy is horsepower...but you gotta control the heat.
-Carl

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