furiousman
Member
well today my son and wife check the compression and this what we found / cyl's 1,3,5,7 are 154 to 155/ cyl's 2,4,6,8 are as follows cyl 2=180/cyl 4=150/ cyl 6=140/ cyl 8=170 are numbers within range or not please help
furiousman puzzled
- Thread starter furiousman
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bremereric
FMJ Body Moderator
Probably the heads then since they are all on one side.
ramenth
Well-Known Member
Optimum would be only a five pound variance from cylinder to cylinder. (That's optimum... on a fresh engine). But from what you're showing even the weakest on your engine has plenty of pressure to fire. How many miles, what's the ignition set up (lean burn or not), what's the carb's tune? Too me, this all reads pretty normal on a high mileage engine.
furiousman
Member
87 plymouth gran fury 318-p egine approx 75000 original miles an old police car w/electronic fuel control box on air cleaner im asuming lean burning
ramenth
Well-Known Member
Yup, that's the Lean Burn.
Being an AHB, though, I'd almost guarantee that the 75,000 showing on the clock has been turned at least once. Which would explain the variance in cylinder pressure. If you're still chasing your driveability issue, these numbers won't be causing the problem. As a matter of fact, since someone threw out the idea of potential plugged cats, these numbers pretty much shows they aren't.
furiousman
Member
hey this is his son. This is what im finding. as i go to turn the key its getting fuel i can smell it undeniably when i do get it to crank it sounds strong when i floor it but as soon as she warms up i get nothing but a real loud air sucking when i go to floor it im thinking its idle air mixture would i be correct in my thinking
alf44
Well-Known Member
vacuum leak? check the carb to intake gasket. as she warms up you can get a very bad leak
