Piston Rings

[bsbn]

Combustion chamber sealing is very important for performance, what kind of rings do you use? are brands like speed pro worth the extra money?

[DartGT66]

I use Childs & Albert ZGS rings in my 'better' engines, and just any rings in others. I have been very happy with the ZGS's, there is no measurable blow by with them after one years use.

[340king]

From what I have gathered in recent conversations with my engine builder, there are two schools of thought.

1. Keep all the combustion gases in the chamber using gapless ring technology.

2. Use a sizable gap in the top ring (.016"+) and let the second ring do some of the sealing.

Which theory is right I don't know. There are good arguments for both sides.

The only thing that I have heard and seen on gapless rings is that in all out racing applications the top ring can flutter due to a lack of pressure difference across the ring face. My engine builder believes in the second theory. I have used Total Seal gapless rings before and had very good results with them. I did however notice quite a bit of top ring wear(.004") after 50,000 mi of street use and 20+ nights of circle track racing, but that is what I would expect out of any ring.

[sanborn]

We have used Total Seal for several years with very good results. We replace the rings after 1600 laps but probably go further with little increase in leakdown. One problem I have seen in other engines however, if you get water temp over 250 F the 2d ring set loses tension and leakage begins. We just use the instructions for ring gap. One real plus for us, they sure help to pull a crankcase vacuum and that helps oil control.

[PRO]

One important note on hypereutctic piston rings,these pistons are denser than cast and therefore retain more heat,remember heat is power so lost heat is lost power,but they require more ring end gap because of the extra heat which causes the ring to expand more,KB reccomends .028 for a .030 over 440 whereas a stock piston ring combo would run .017,overlook this and youve just added a ton of heat and friction to your cyl. wall.I like to buy my rings from my piston supplier for street/stock combo's.also Hypereutectic pistons dont expand as much so you run a tighter wall clearance.The bottom line is to follow manufacterers recommendations...PRO..

[This message has been edited by PRO (edited December 02, 1999).]