Crazy High Compression - 260 PSI... Even possible?

[Rickster]

No, it is all in the base gasket in this situation for sure, hands down.

Last year when I ran the motor, compression was around 185ish running this thicker base gasket.

This year when I reassembled the motor, I replaced the gasket with good intention, but in all honesty did not think twice about the thickness of the old compared to the new (high-on moment).

If you saw the two side by side, you would understand and is definitely the problem. The only thing changed from last year is a 1MM bore up and a rebuilt crank.

-Andrew

Ok, not sure how thick the base gasket is that you replaced, but if it is significant, then definitely would be the cause.

Good luck..

 

[NJJer]

If that was really 260psi, that engine would have gone POP a long time ago on 94 octane.

Throw that gauge away and get a good one.

Test both plugs out, fully charged battery, throttle wfo so it can ingest air.

 

[Grant]

of course its possible...

you could have some extra oil in the cyl..that'll make it read high...

t

what I was thinking also. Your oil ratio is high any extra oil will cause high reading. But heck that is really high

 

[K&S Kuwait]

it is possible because your raves are closed

Check the compression with raves open
that would be your wot compression
raves =power valves
what os your bore And strock and what
domes are you using

 

[nightrider05]

I would say its the gauge...if you get a bit of water or oil in those gauges from a previous test then they will do that.