Hi guys
I have done a few searches on this but to know avail!!
My question is how come most rx7\'s have lower. Compression on the rear rotor, compared to the front? Even after rebuilds?
Does Anyone have a solid answer to this?
Thanks
Rob
Because the back of the engine is hotter allowing more expansion.
It is not allway\'s the case though only most of the time.
Regards
Carl
Ah
that makes sense, thanks! Had been bugging me, I new there had to be a logical explanation!
Thanks Carl
Carl, Is it true that a street ported engine will have lower compression readings than a stock port?
If so what compression readings should a large street port rebuilt with new housings, plates and seals have ? roughly.
Chris
In my experience, the porting doesnt make that big a difference to starting compression. I test Eds engine old engine last year that had a large street port on it and it came out with mid 8s. My bridgeported engine in the orange RE-A car had mid 7s. Id say static compression is more a function of apex seal used, seal springs and sideseal clearances. Also compression is measured on the spark plug side of the engine (opposite side to exhaust or inlet port)