What piston rings?

[BoostedSUV]

Ok I've done some research and I'm getting mixed opinions. My engine is all apart (after less than 500 miles) and I wasn't going to replace the rings during reassembly. Looking at the cost of rings I figure I'll just change them. Dropping the block off Saturday for machine work and I'm planning out the parts for me to assemble it.

SRP pistons, 4.030 bore... Now the questions are: which brand should I go with? What material? File fit or no? (I'm thinking file fit is the answer) what is the recommended ring gap? .020-.022 maybe? Anything else I need to think about?


Decided to go with clevitte main/rod/cam bearings. Just need to figure out rings or maybe everyone will say just use the perfectly good ones I just took out. Lol

 

[Don W.]

Re: What piston rings?

FWIW I'm running Total Seal gapless top with the napier second ring. File fit is great if you have the tool and patience. I would definitely recommend a tapered ring compressor. makes assembly a piece of cake with virtually no chance of breaking a ring on install.

My machinist did the file fit so I don't know the gap.

 

[Aeroking]

Re: What piston rings?

i did Seal Power rings on the last motor, and Total Seal on this motor. Both file fit gapped at 25 on the top ring. They never broke, so i have no results lol.

edited: i believe total Seal says 0.007 x bore for top ring gap for boost

 

[Z SKI]

Re: What piston rings?

If you end up running total seal rings they have changed their boosted application end gap.. I was going to file them to the boosted specs that were on their instruction card and when I called them they told me that was for low boost.. If I remember correctly they had something to the effect of; low boost <10, medium boost 10-25, and high boost >30... Don't quote me on the exact boost numbers... Give them a call and they will lead you in the correct direction..

See ya,

 

[BoostedSUV]

Re: What piston rings?

FWIW I'm running Total Seal gapless top with the napier second ring. File fit is great if you have the tool and patience. I would definitely recommend a tapered ring compressor. makes assembly a piece of cake with virtually no chance of breaking a ring on install.

My machinist did the file fit so I don't know the gap.

it's about $50 for a ring filer so considering what I'm going to save by assembling the motor myself thats no biggie... also it's about $12 for an adjustable ring compressor. I have a couple different varieties of engines I can potentionally be working on so I have to go adjustable.

I've heard mixed results about the gapless rings with boost :dunno:

i did Seal Power rings on the last motor, and Total Seal on this motor. Both file fit gapped at 25 on the top ring. They never broke, so i have no results lol.

edited: i believe total Seal says 0.007 x bore for top ring gap for boost

Those were the 2 brands I have been looking at lol

If you end up running total seal rings they have changed their boosted application end gap.. I was going to file them to the boosted specs that were on their instruction card and when I called them they told me that was for low boost.. If I remember correctly they had something to the effect of; low boost <10, medium boost 10-25, and high boost >30... Don't quote me on the exact boost numbers... Give them a call and they will lead you in the correct direction..

See ya,

thank you, I guess my best bet it is to call when I decide on manufacture

 

[berzerker]

Re: What piston rings?

I run the file to fit je rings . end gaps @ .28 upper and lower rings.

 

[Don W.]

Re: What piston rings?

My machinist makes blown motors but not turbo motors. He uses Total Seal so I went with him and had him gap them.

Here's something I found very interesting: I was baring the motor over today and on every cylinder as I came up on compression and stopped it held compression. IOW if I relaxed a bit it would literally push the bar back to almost where it started. I have NEVER had happen before. In the past as I bared against compression and then stopped you could hear the rings leak down and there was no push back. I am now sold on Total Seal.

 

[Osmosis]

Re: What piston rings?

The shop I take my parts to has a machinist who swears by the Total Seal Rings. Next engine build I do, I will use them :tup:

 

[BoostedSUV]

Re: What piston rings?

Aren't total seal rings gapless? I would think for a street motor you wouldn't want a gapless ring. Interesting. My current rings leaked less than 5% so I can't imagine 0% being good on parts.

 

[Don W.]

Re: What piston rings?

Yes they are gapless. Look at their web site or an ad. You'll see how they do it. Clever.

 

[TYRODD]

Re: What piston rings?

Interesting: http://www.totalseal.com/TechPage.aspx#trGaplessPistRings

 

[Don W.]

Re: What piston rings?

Thanks for the suggestion. I did, and learned some stuff. (Particularly regarding sealing on the intake stroke in NA engines). I have one observation / question:

When the cyl fires, the ring is blown downwards, sealing against the bottom of the groove. Gasses then flow behind the ring, and force it outwards against the cyl walls. A ring requires pressure behind it to establish an adequate seal.

With a gap-less, low blow-by top ring, how does the second ring seal, or does it just go along for the ride until needed as a back-up to a worn and now leaking top ring?

The way I see it the ring and the rail run as a pair with ring forcing the rail out with it because if the way the ring is interlocked with the rail. The sole job of the rail is to seal the gap in the ring regardless of its size. By way of clarification both the ring and the rail have a gap, they're just not aligned.

HTH