I thought that was what you were eluding to, some sort of modified/altered PCV circut that had the ability to maintain crankcase vacuum at WOT. PCV is effective for part throttle cruising, but not WOT which is what most of us are interested in

-brent

 

Nope, as far as I know it's low tension rings that still maintain a seal well enough to use the existing technology. I didn't mean to mislead.

Realistically, on a street car, or even a dual purpose street/strip car, how often is WOT a concern, from an OEM or personal standpoint.

Maybe if the CARB starts checking emissions at WOT OEMs will devise a system.

 

Im pretty sure Ive heard people talk about this, but couldnt you hook up a factory AIR pump to turn on with a "window" type switch at say 50% throttle to suck crankcase pressure and evacuate into either the intake or, for non-tree huggers, to the atmosphere. AIR pumps are able to make about 5-8psi into the exhaust stream so wouldnt that be enough vacuum to suck WOT crankcase vapors?

 

The stock LT1 air pump is good for this use. Old schoolers use them as crankcase pumps as you say (cheap pump-advantage). Vent to the atmosphere only. At 100% duty cycle the pumps don't last long (drawback). A trigger is a good idea.

 

Gas ported pistons are an "optomization" of the standard piston. During operation compression and combustion pressure pushes on the backside of the top ring forcing it ******ds. Gas ports increase the area available and offer a more direct path for the pressure to accomplish this. When building an engine to this consideration the ring is usually backcut to reduce its radial tension lowering the friction during the intake and exhaust stroke. Combined with a thin ring package gas porting can provide an optimal seal and reduced motoring friction. The loading on the rings and cylinder walls increases though during compression and power strokes greatly increasing the wear of those components, thus providing a short life. Side porting is generally used as a "cheat" when the rules specifically disallow gas ports. During a head off inspection the side ports cannot be seen. ie: Stock and SuperStock. Carbon buildup is not a problem for wot only applications, but deffinitely is unsuitable for street use. Dykes and headland rings are varations on the gas porting thinking. The dykes ring is stepped like an L and allows combustion pressure to get behind the vertical part of the L pushing the ring ******d.

TotalSeal offers a gapless top ring that will really seal up a engine and testing during prostock truck times showed a need for less jet on the carburetors, the signal improved substantially. Plus a 5-8 hp increase on a highly optimized combination.
Tight ring seal improves the response and power of any engine, but good seal during the intake stroke will improve it further.

Why is o-u-t-w-a-r-d a dirty word on this forum?

 

Try out-ward.

 

Thanks.

 

Well with the Total Seal Gapless Top ring quote you are going to find some friction from some of the members here..... I'm not one of them.

Good seeing you here Mark.

Bret

 

I thought that most of the problems were with gapless second rings.

 

Yeah but that poison is still in the water for most guys....

 

Yea, well, I’m not sure that I’m really over it, but OTOH, I’m not really in the mood to build anything NA lately so I’m willing to give up a little in overall efficiency in the interest of overall durability… I can always turn up the boost ½psi to make up the difference.

If I had a serious belief (hell, convince me) that it would be as durable a setup I would probably use them in my next build… Maybe I should anyway just to get some empirical data on my own.