will be ordering pistons and rings in the next week or two. ordering wiseco nitrous domes for the 410sb. will be 4" stroke 13.5:1 and spin between 7000-7500 shift points. n/a application and will see some street time. looking at total seal for rings. the pistons use the .043/.043/3mm ring. what should I get, file fit or gapless? why? thanks

I'm almost sure that Total Seal doesn't make, use or recommend a gapless ring in .043, if they do I wouldn't use them Get a really good set of rings for the dual purpose appilcation with that much compression I'm not sure if the top should be moly and a second Napier iron ring or which package is the best for your deal, sorry

No gapless....

ok, thanks to both of you. i will stay away from gapless. just curious to why?

I just spoke to Total Seal about rings for my 434 build, pump gas street/strip deal, probably 11.3-5 to 1 compression, solid roller 260-270 @ .050, low .700 lift with Indy 360-1s. For this combination they recommended a gapless top, napier second and standard tension oil ring, 1.5mm, 1.5mm, 3.0mm.

IMO it is a "gimmick" 99.9% of the time Total Seal will recommend something other than gapless. Total seal I think might agree if cornerd and also likely why they went to a gapless top ring. IMO it is just old antiquated thinking.

To oversimplify it. The issue is with a gapless second you will loose ring seal on the top ring due to increased pressure that gets trapped by the second gapless ring. Nowadays most top engine builders actually OPEN up the gap on the second ring to allow any excess pressure to be forced down, also helping to scavenge oil off the cylinders.

Use a gapless top. Open the second a bit.

The reason I use them more than most is that most guys don't want to experiment with end gaps. I have a BLOW BY METER that I use on the dyno and under load the gapless are ALWAYS better than gapped rings that are nottested. Most times, you can run the minimum gap called out, or a little less, as long as you torque plated the block and use the torque plate to gap rings.

i just called total seal myself to get a part number for rings i will need. they recommend gapless top for my combo as well. $347/set, ouch!
what do you like to see for ring gap on second ring?

Gapless top rind is a diferent deal. Still while I do not hundreds of engines under my belt I try to surround myself with smart people who do and most will say they don't like them. They do give the end user a false sense of calm with leak down numbers for sure but most top tier guys do not put a lot into leak down numbers either. Compression numbers yes, leakdown not so much. I could see why some engine guys use them for that very reason alone. They will show excellent "seal" with a leakdown test so makes them look good.

FWIW $347 for a set of rings is not bad at all. My predator stuff was about $1500 more than that, just saying. As for the second gap depends on intended use, block material and ring selected IMO.

They definitely do make a gapless .043 Top..........would I run them......NO. Am not a fan of gapless top rings. The reason is they never SHOWED me anything in regards to POWER. Great leakdown numbers and less on the blowby meter is fine, but does that equal more POWER and the car running faster. In our own Super Stock motors, that was not the case and we tried every ring combination there is

That's basically what I was saying. Without a blowby meter (or something similar) you only have leak down and compression testing and the gapless top always looks good in those.

The only issue with using the blow by meter is using vaccuum pumps and dry sumps. You can't use the blow by meter with them (at least I have not found a way to do it yet) so it will skew readings and make a good ring package look bad. As with all testing you need to be very careful otherwise the numbers mean nothing.

I usually start with the second ring gap in the middle of what is called for in your application.

I'll chime in.
Don't like gapless rings tried it both ways with and without. Engine vacuum the same engine performance the same when the rings a worn out the leak down will still say it's good.

It's a waste of money and all the time it takes to file fit so why run them no performance bump no benefits.

Did you say NOS pistons? So..you are going to spray?
I would think that a 1/16th NOS ring package would be in order
Skinny rings are hot right now and make more HP but in a Spray Motor?? Not me..
Gapless has never shown me more HP on the dyno--they make great leak down test--I would maybe use them in dirt track engines that eat lots of dirt , hoping it might delay fresh up a little but even that is big maybe
I think from all I have seen and built it is a gimmick and and expensive one!

A few years ago I tried gapless rings when I freshened up the motor in my Demon. It was a wast of money. I saw zero difference in performance or anything else except less money in my pocket. I also ran a small shot of nitrous sometimes.

No. That's just what wiseco named them (nitrous dome). This is a n/a engine. The total seal file fit .043 is still pricey at $189.

Price a set of 1.5, 1.5, 3.0 mm, $297 for traditional ring and $387 for a gapless top ring.

do you think that the total seal rings are the best performance rings to buy?

We run .043 top and second rings in 900" nitrous motors that spray 1200+HP of nitrous, in addition to the 1600 they make on nuts

IMO, no. They offer rings in a whole bunch of sizes and styles, but I don't think that means they're the best. Not that they make bad rings (I've used them before and will again), but Mahle, Hastings and Speed Pro make a good ring, too.