~Ring Gap~
 

What does everyone think is a safe ring gap? I have been building race engines for about 26 years and always used settings like 22TOP' 14-16 SECOND' on engines running around 150-200 shot of NOS. A few years back started using whatever the ring brand reccomended... My last 427 stroker ran 28TOP 26SECOND.... Ran good and felt plenty safe...Just got off the phone with BENNETT RACING' and they set all their rings on 28TOP 28SECOND. He said they do this on all their engines from the small strokers up, and street machines also, when running 250shot & up. Cant argue with the guy's that build the motors that run the way Bennett's motors do! So i started doing all mine on 28/28, on motors running that much NOS. I see engines everyday come back where they were running tight gaps' and wind up with burnt pistons and all! Read a long page last night where Federal Mogule done some test and are now telling race-engine builders to run a larger gap on the Second ring than the top! They say test have shown' improved blowby, and picked up a few horsepower....I have also been running the Hellfire Rings that have been out about a year' they r some really tough rings for people running alot of NOS' or other power adders
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In the old days I always ran a smaller gap on the second ring (less temperature, less ring expansion school of thought). Those were N/A applications though. In recent years I have been running the same gap on both compression rings due to my blower application. On my current R-302 331 (4.030" bore) I run .024" top ring and .026" second ring, pushing ~18 psi boost from the NOVI 2000. These are Childs & Albert moly faced rings on forged Probe pistons. Basically what I'm saying is that I buy into the new "top ring flutter" theory, hense the larger second ring gap.

I alway's go with the piston and ring maker's recomindation but i also like the gapless ring's they join high low and i believe break in has alot more to do with blow by than ring gap .

I believe that a engine broken in under load with loading and unloading seats better than babying it for 500 miles just my 2 cents and i also recomend spending a few dollars more for quality rings. and i think every performance engine has used the same ring gap.

I agree with the larger second ring gap and flutter theory as well...we will most likely see this from ring manufacturers in years to come. I've even heard of some guys going extreme and running as much as 50% more gap on the second rings.