hey guys, i did a compression test on the rebuilt motor and it shows 180 across the board on either 8.8 or 8.6:1 pistons, i can't remember which off the top of my head. Now, i know that if timing is off, compression is going to drop heavily, so someone explain to me what the fuck is going on here?!?!?!?! Thanks...
#69535, "RE: compression fine but timing off?" In response to Reply # 0
Are you saying you think your timing may be off because the numbers are as high as they are? Have you checked the markings on the crank and gears? If the timing is good by the marks and you get 9.6:1 CR numbers, then that would be weird imo.
#69541, "RE: compression fine but timing off?" In response to Reply # 1
180 psi compression on 8.8:1 or 8.6:1 are good numbers for that setup. With 9.6:1 compression you should be seeing 210ish across the board with a fresh motor.
Anyway your compression numbers are perfect. Nothing is wrong. They are right where they are supposed to be.
#69553, "RE: compression fine but timing off?" In response to Reply # 2
Timing, as in ignition timing, affects compression results?
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#69556, "RE: compression fine but timing off?" In response to Reply # 3
180 pretty much seems to be the norm. I did a test this weekend expecting to see low numbers and came up with 190-190-192-190. i was elated to say the least. why do you think your timing is off, what gives you this impression?
#69565, "RE: compression fine but timing off?" In response to Reply # 4
hey guys.....well, i figured it out, my timing was off by a tooth, got it fixed and now the car lives again! As for the compression question, i don't mean ignition timing, i mean valve timing. If your valve timing is off, your compression will be low depending on how advanced/retarded you are. That's what i meant, but anyway, found the problem and fixed it and now the car runs great! Thanks for all your help fellas, and by the way, does anyone know the limit of this setup? What is the psi limit that i want to watch out for? I just bought the howell performance bottom end rebuild kit, and i have the star stage 2 (t3/t4 with e trim)...Am i looking at anywhere up to 20 psi, or am i off? Thanks again guys!!!
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