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

General engine tech -- Drag Racing to Circle Track

Moderator: Team

Post Reply
rewguy
Expert
Expert
Posts: 785
Joined: Mon Jun 12, 2006 2:45 am

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
Guru
Guru
Posts: 1317
Joined: Tue Mar 06, 2007 7:23 pm
Location: Torrance, CA
Contact:

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
Guru
Guru
Posts: 3117
Joined: Tue Aug 19, 2008 7:20 am
Location: South Australia

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.

Frankshaft
Guru
Guru
Posts: 1034
Joined: Sun Jul 05, 2015 6:01 pm

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.

rewguy
Expert
Expert
Posts: 785
Joined: Mon Jun 12, 2006 2:45 am

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.

engineguyBill
Expert
Expert
Posts: 930
Joined: Fri Feb 26, 2010 11:15 am
Location: Gold Canyon, AZ

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.
Bill

SAE Member (28+ years)
ASE Master Certified Engine Machinist (+ two otherASE Master Certifications)
AERA Certified Professional Engine Machinist

"Do what you can, with what you have, where you are."
- Theodore Roosevelt

steve316
Pro
Pro
Posts: 465
Joined: Fri Apr 13, 2007 10:06 pm
Location: St.Joseph,mo.

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

steve316
Pro
Pro
Posts: 465
Joined: Fri Apr 13, 2007 10:06 pm
Location: St.Joseph,mo.

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?

ProPower engines
Guru
Guru
Posts: 7300
Joined: Sun Jan 21, 2007 1:16 pm
Location: VICTORIA BC CANADA

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

rewguy
Expert
Expert
Posts: 785
Joined: Mon Jun 12, 2006 2:45 am

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.

Post Reply