150 140 139 150 150 158 140 162 -------- FRONT I know the 10% rule, so I'm just barely out of that, any thoughts?
What sorts of problems are you having that prompted a compression check? Maybe you need a valve job...
This was preemptive, since I replaced the cap, rotor, plugs, and wires, it has been running a lot better, but it's still not running smooth.
Points? Condensor? Does it have the original plastic cam gear on the timing set? Carb? Just some thoughts. I hate trying to diagnose via keyboard...
306ci KB flat top pistons (with 6cc valve reliefs) eagle i-beam rods stock crank tfs stage 1 cam (.499/.510 w/1.6's) ASF 32 heat range plugs gapped 40 1.7 roller rockers (changes the cam specs I know) hooker 6901 headers e7te heads, shaved ~9.5:1-10:1 comp weiand 4011 intake holley 600 carb vac 2ndary. #70 jets mechanical fuel pump pertronix in-dizzy ignition running ahead of a c4 and 3.00 open rear doubler roller timing chain.
Oh, nevermind. I thought we might be talking about a stock engine. Actually I don't know why I thought that... I have seen your specs listed before. :doh:
I don't think it's that bad, you are planning on changing heads aren't you? You can do more investigating then. I would worry more if you went under 120. Did you try the oil trick in the low cylinders? Leak down test would be better too.
in my experience with compression tests. the temp of the motor staying consitant is very important. if you lower pressures come in towards the end of the test then i would dismiss them as the cylinders have cooled off a bit and if the bat. charge has droped a bit cauisng a lower cranking speed. i dont see any real problem with those results. a perfomance cam can cause lower comprssion test results due to the valve over lap.
Last 2 posts were excellent points. The numbers didn't concern me much because they were high numbers for a dry compression test, even if they are spread a bit. I like the idea of combining the last two posts... Keep a battery charger on the car to keep starter speed as consistent as possible. Do a dry test first. Then do a wet test. Then do a leak down. Keep a running tab of all the numbers, but don't analyze anything till all results are in.
3 x agree+(plus) check push rods, geometry and rocker arm contact patch on the valve...since the e-7's where milled...possibility that a valve might,or be carbonized a little and flow a little less on that cylinder... last rebuild I did(72 302) with new cast pistons netted between 90>110 psi dry...with a CC 268H,8to1 mechanical compression and no issues...I aways go for 5 hits on the compression gauge...
