Timing.
OK that's an indication of high compression or hot spots usually due to deposits. The higher octane resists detonation. I don't remember if we did this already but make sure timing is set to factory specs (10* btdc with the spout disconnected) then do a good seafoam treatment and see if that helps you out. It would also bee a good idea to do a compression test before and after and note any difference.
OK that's an indication of high compression or hot spots usually due to deposits. The higher octane resists detonation. I don't remember if we did this already but make sure timing is set to factory specs (10* btdc with the spout disconnected) then do a good seafoam treatment and see if that helps you out. It would also bee a good idea to do a compression test before and after and note any difference.
BTDC= Before Top Dead Center. You will need a timing light. Mark the 10* btdc mark on the damper with whiteout or chalk so its easy to see. Run the engine up to operating temperature. Disconnect the spout plug. Shine the timing light on your timing marks. Turn the distributor back and forth until the marks line up. Tighten the distributor and recheck timing. Replace the spout. Check the timing and rev the engine up above 2000 rpm. The timing should advance to about 20 btdc then lower when you return to idle. The compression test is pretty simple. All you need is a compression gauge available for under $20. Just screw it into the spark plug hole. Hold the gas pedal all the way to the floor to disable the fuel injectors while cranking the engine. Read the psi and write it down. Repeat for each cylinder. There should be less than 20% differences between cylinders. Doing this before and after a seafoam cleaning will tell you if you removed a lot of carbon (lower psi all around) or if a leak developed. (Low psi in only one cylinder)
Okay. Progress is what's being made here lol. Well I'm not off for a another week. So I'll post an up date when I'm not at school or my 2 jobs. With the timing set back to factory spec, compression tested and I'll let you know how everything goes.

