JEFF69Z28

WHAT CAUSES HIGH CYLINDER PRESSURE?

wmeabates

Jeff,Did you set your timing pointer to your damper using a piston stop? Bill.

JEFF69Z28

I did not build the engine,thats something else i read about to see if the timing mark is in the correct spot..how can i do that now that the enginge is together,is there a piston stop that can be inserted in a plug hole.

desoto30

Not that I know of But I made one by cutting the guts out of a spark plug & welding a piece of steel in that protruded into the cylinder area thereby not allowing the engine to rotate past the bit sticking in. Obviously you will need to be able to turn the engine over gently so as not to bend it.

wmeabates

Yes someone makes a stop that goes in the plug hole.Remove all the spark plugs and it will be easyer to feel the piston hit the stop.Bill.

desoto30

& if the engine has any sort of big valve springs I would also back them off also

Tod74

Higher compression, Nitrous, turbo, blower, cam timing....whatever. That's the whole point. The more air you can pump through the engine the more power it will make..think of an engine as a big air compressor. An engine with 12 to 1 compression has 12 times the amount of air in the cylinder at BDC as it does at TDC..The more air you get into the cylinder on the intake stroke the more cylinder pressure you will have when it's compressed, therefore more power on the power stroke. Again, maybe poor wording because valve timing effects the cylinder pressure too but that's pretty much how I think of it.

DirkaDirka

Ok what are things you can do to achieve higher compression ratio??

markdunlap

You can use a threaded positive stop in the spark plug hole to find true TDC. BUT BEFORE YOU USE IT, take the rockers off that cylinder or you can bend the valves.
If your balancer is marked in degrees before TDC, screw the positive stop in to stop at 30 degrees. Then measure carefully the distance from zero to 30 degrees and put a mark on the other side of zero at that measurement. Rotate the engine backward slowly till it is against the the positive stop again. If it stops at 30 degrees, your timing pointer is correct. If not, move the pointer until it is equal degrees on both sides of the positive stop.
If you only have a zero mark on your pointer, just pick any measurement around 1 inch and put that on both sides of your zero mark and move your pointer until the measurement is equal on both sides of mark.
Morroso, Manley, MR Gasket, Comp Cams and others make an aluminum threaded positive stop.

JEFF69Z28

WHEN THE #1 PISTON WAS AT TDC THE ROTOR IS POINTING AT THE NUMBER 6 CYLINDER AND THE #1 PLUG WIRE IS IN THAT AREA ON THE CAP SHOULD I PUT MY TIMING LIGHT ON THAT WIRE?OR SHOULD I TAKE THE DIST.OUT AND HAVE THE ROTOR POINTING AT NUMBER ONE.BOY AM I CONFUSED!