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Compression


NewGuy

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I don't think that's too high - with that CR if you use 98 fuel and get the ignition timing spot on you could take advantage of a bit more power.

When my old Galant blew it a headgasket, it still had 185psi on all cylinders (the leak was only between an oil gallery and a water jacket) - after I took the head off and sent it away to be reconditioned the compression came back varying between 205 and 225psi depending on the cylinder - which would make sense as the engine builder shaved the head a fraction and fitted new valves etc. I think now looking back at it, that increase of compression may have been what caused the bottom end to let go some nearly four years later.

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you said your cam timing wasn't quite right? Get that all sorted then see if you can get it on the dyno for them to adjust timing at optimum point and to check the a/f ratio isn't leaning out when it shouldn't be. I did that not long after I did the head on the Galant. You recently fitted new bearings and rings eh?

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you said your cam timing wasn't quite right? Get that all sorted then see if you can get it on the dyno for them to adjust timing at optimum point and to check the a/f ratio isn't leaning out when it shouldn't be. I did that not long after I did the head on the Galant. You recently fitted new bearings and rings eh?

Brand New bottom end.

The caming timing is right but after the skim it needs to be retared?

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Carbon coking in the cylinder will also contibute to a higher c/r, to the extent that it can even mask the symptoms of bad rings...

Was it you talking about detonation in another thread as well? Because carbon will also cause hot spots in the combustion chamber that are BOUND to cause pre-detonation as they near the flash point of the fuel.

Either way I would definitely be running the highest octane fuel you can buy ie BP Ultimate or Optimax 98 just for piece of mind, as retarding your timing will bring about it's own problems.

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