Originally Posted by WAGS382

Bill
Thanks for the advise.
I agree with you that I need to find the problem. I think it is a mild case of water reversion. If I pull the O2 plug when idleing I get water vapor. The back cylinders (7and 8) were not affected, the others have a straighter shot at the exhaust valves.

Kamma
I was told not to use the copper berillium seats because they are too soft and won't transfer heat properly.
I was also told not to use the propane seats because they are too hard. I am not sure who to believe.

Originally Posted by RunninHotRacing158

I was told not to use the copper berillium seats because they are too soft and won't transfer heat properly??????????
Learn sumtin new every day

Originally Posted by KAAMA

Yes, I have AFR heads w/230hrs or so, but I am not currently experiencing any seat problems---at least none that I know of at this point. I run Stellings full length tubular dry headers. The cams I am running (hyd roller) are easy on the valve train and have very little overlap....so, pretty slim chance of any reversion. The cams came from RMBuilder.

A few weeks ago there was a thread regarding "Copper Beryllium" seats and it sounded like they are supposed be the chit as far as durability (rust), valve bounce dampening effect, but I truely do not know either. I think I may have asked my engine builder at one time a few years back and I forgot what he said. I wouldn't mind using copper beryllium seats the next time I rebuild.

Laz, what is your take on copper beryllium seats in either a steel or aluminum head?

Originally Posted by RunninHotRacing158

I was told not to use the copper berillium seats because they are too soft and won't transfer heat properly??????????
Learn sumtin new every day