90 lbs compression and runs great!

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Midijamm

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Is it possible?
I have a 95 GTX that I have been fixing up. I originally opened the engine partway up and saw the pistons and rings thru the intake ports and they looked like new (not a scratch) so I buttoned it back up and started it and voila it ran perfect out of the water. After a few false starts I got it working in the water and it screams. A fulll 50 something mph, no hesitation, perfect idle, strong hole shot, but.... after fifteen or twenty min fouled plugs. fire jumping from plug wire end to head with plug wire loose on plug (trick to get hot spark) Checked compression ...90 on both cyls. Can it be true or is the tester bad?

I don't have enough experience with these machines to know if they would even run with that compression much less run that strong?

Anyone here can enlighten me? Thanks :O)
 
Your tester is bad.

There is no way it would run good or even start in the water with only 90 psi compression.
 
I agree, definitely a bad compression tester. At 90 psi you MIGHT be able to start it on the trailer, but no way would it run in the water.
Also curious why you are running with loose plug wires? With a good running ski and clean plugs, I don't see what the advantage would be
 
I agree, definitely a bad compression tester. At 90 psi you MIGHT be able to start it on the trailer, but no way would it run in the water.
Also curious why you are running with loose plug wires? With a good running ski and clean plugs, I don't see what the advantage would be

After ten fifteen min the plugs foul and it won't start or run with the plug wires all the way tight. Have to put new ones in every time tto get it to run without them loose (NGK BR7ES)
 
You are already running a hotter plug. Stock plugs should be BR8ES. Check the setting on the injection pump. If that's good, you probably have RV crank seals leaking.

You could also try trimming back your plug wires and see if that helps
 
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You should only be running BR8ES plugs. If your oil pump is set correctly it’s probably your carbs running rich as it isn’t just too much oil that will foul plugs.
 
You should only be running BR8ES plugs. If your oil pump is set correctly it’s probably your carbs running rich as it isn’t just too much oil that will foul plugs.

I keep seeing references to rectifiers causing weird problems and I wonder if something is going on there (electrically) I had a water leak spring from the boss on the extractor pipe and it squirted right on the plug that goes into the Mag. It blew the main fuse... replaced it got it dried out. Had the pipe welded up. That was all at the beginning and I wonder if it has anything to do with this issue. The oil pump timing is right on. Maybe it is a weak spark issue fouling the plugs?? I don't know what the rectifier would have to do with it unless the electrical system wasn't up enough to power the coils enough???
 
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