Reckless

iTrader: (9)

Gonna be building my new motor soon. What is the best ring gaps to use for NA and occasional N2O use? They are Wiseco thermal coated pistons (4-inch bore) with the usual ls1 hipo rings (forget the brand).

LOnSLO

iTrader: (15)

.024, .024, .015. Top, middle, oil rings.

Reckless

iTrader: (9)

Thanks LO...anyone else have a differing opinion?

LOnSLO

iTrader: (15)

Todd, those are obviously just ball park numbers. Little on the loose side on the top 2 rings for nitrous use.

Country Boy

iTrader: (24)

From Chris @ Diamond...

Reckless

iTrader: (9)

That is quite different. And what about the oil rings?

Country Boy

iTrader: (24)

Hummm.. didnt know you had to file fit oil rings since they are just scrapers.. Hafta check on that one

1dirtyZ

iTrader: (1)

i thought the rule was .04 inch for every inch of bore??

Jimmybob

for an LS1 or Ls6 top ring .16 middle ring .12 oil .08

Reckless

iTrader: (9)

So the concensus is that no one can agree on this

Any full-time builders want to chime in? ARE? MTI? FMS?

1999_SS_M6

I may as well chime in too.. This is how I would set the engine up for Street use with light NO2.

TOP RING: .006 per inch of bore dia.

MIDDLE RING: .005 per inch of bore dia.

so in your case, .024 on top, .020 in the middle.

98 Silver Bullet

iTrader: (28)

OK.....which is it? One person says .16 and another says .016. One person says .04 per inch of bore and another says .004. WTF

Country Boy

iTrader: (24)

Hey Reckless.. I got the email back about the ring gaps from Chris. I asked him if he agreed with what he told me before and here it is:

Reckless

iTrader: (9)

I thought the oil scraper was the bottom ring? Last time I did rings, I had to file the top two I believe, and did not alter the oil ring (scraper on bottom). This is getting more and more confusing

1999_SS_M6

Well, I will stake reputation and ASSURE you that it isn't .040 per inch of bore. I just think that .004 is too tight for a nitrous motor. That's fine if you want to go NA, but with the extra heat and pressure, if you go too tight on your top ring, you're going to pop your top ring land and grenade the motor.

Look at it this way, if you give it a few extra thousandths on top, you may sacrifice 10-15 PEAK NITROUS horsepower, but wouldn't that be worth it as insurance if you ever overheated the engine?

There are lots of tricks to running nitrous safely.. You can get a piston that puts the ring lands further down from the top, you can increase gap, yada yada.. There is no "RIGHT" way. Just several different preferences that engine builders use. Don't believe me?? Call 4 REPUTABLE engine builders and if you get the same answer from all 4, you can use my lift to do your motor swap!

Country Boy

iTrader: (24)

LOL

You have:
ring land 1 (top) compression ring #1
ring land 2 (second) compression ring #2
ring land 3 (bottom) Oil scraper ring (has top scraper, senter expander, and bottom scraper)

You dont touch the middle one (the funny lookin' up and down one ) You just file the top and bottom scrapers. You can have a big margin of gap because they arent under any pressure, they are just oil scrapers. Hence why most are low tension

Better?

1999_SS_M6

Bottom line, I'd call your piston manufacturer and ask them... Then call your Ring manufacturer and ask them.. That's the only way to be safe. I don't want to tell you the wrong info, the only motors I've set up for NO2 from the ground up were SBC Iron motors.

GOOD LUCK!

Reckless

iTrader: (9)

OK guys, I have done this before for my turbo motor, and Nick Agostino didn't make things nearly as complicated as you guys are

So,
Top ring - ???
2nd ring - ???
oil scrapers - ???

You guys are making this way too hard

Country Boy

iTrader: (24)

.016
.018
.015 - .060

Reckless

iTrader: (9)

ttt