drdave88

iTrader: (3)

I have a set of summit racing (silvolite) hyper pistons for my 350 and sealed power standard ring set. I have read a bunch of different suggestions, what ring gap should i go with? It seems to be:

Top Ring: .020 - .022
2nd Ring: .012 - .016

Does this seem right? I haven't heard anything about gapping the bottom ring either. This isnt going to be a huge HP application, lil over 300 to start and down the road, probably still under 400.

Damon

Do what the PISTON manufacturer says for gaps, not what the RING manufacturer says. Piston material and location of the rings on the piston makes a BIG difference in the required ring gaps.

I typically buy a "standard" ring set for whatever overbore the engine has and then gap them bigger from there if necessary. Starting with a "file to fit" set isn't necessary.

If in doubt, go a little bigger rather than a little smaller. Believe me, a few thou extra ring gap is NOTHING. Good ring seal has more to do with the bore (as perfectly round as possible) and the surface finish (proper hone) than it will EVER have to do with a few thou of extra ring gap.

sofakingdom

iTrader: (1)

^^^ What he said, on all counts.

There is no "perfect" ring gap; only, real close, one way or the other. (like many things)

What you have to decide then, is which side of "perfect" you'd rather have the error be towards. Err as little as possible of course; but keep it in the 50% range that's harmless, instead of the 50% range that's DEATH.

In the case of rings, what are the consequences of slightly too little ring gap (say, .001"), vs the consequences of slightly too much (say, even as much as .005")?

Once you shine that light on it, it's pretty obvious what to do.

drdave88

iTrader: (3)

Thanks for the input guys. It just says go 20-40% over what factory ring specs are for the top ring due to being hyper pistons. I still haven't found exactly what the top and second ring should be. Do the numbers I showed above sound accurate for factory standard rings?

sofakingdom

iTrader: (1)

Last motor I built with hypers, I used .024" on the 1st and .020" on the 2nd.

Nothing has tore up yet. Of course it only has 40 or 50,000 miles, so who knows, whenever it gets broken in, most anything could happen; but for a fresh build still under warranty, still OK.