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Discussion Starter #1
So I've decided to switch to a european carb setup and ditch the SPICA system as there's so much that can and has already gone wrong with it. It's been dumping gas into the pan for a while now, so that's an $80 oil change out the window (I paid for the good stuff). I decided to to a compression test to see what kind of health the engine was in and got a solid 160-165psi across the board dry. Didn't do a wet test as I ran out of time because I'm working on it at school and had to leave. I was told this was good in general for any engine, but is this good specifically for this engine? The car has a little over 38,000 miles on it and still appears to run absolutely superb.
 

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Standard pistons or high compression, cams stock or otherwise, cams timed with lots of overlap or not. Throttle open or closed, engine warm or cold. All plugs out or just individually as you went.
 

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Discussion Starter #5
All completely original internals and settings, run with 5W/30 for a break in after sitting for 42 years then 20W/50 Valvoline racing oil. It was a 100% cold test (the car has been sitting for a few weeks while I work on it) with throttle 100% open and all plugs out. With the throttle closed it made about 120-125psi. It was also cranked 5 times to get the reading.
 

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I agree with VintageMilano that those are good numbers for a dry compression test on a motor with stock pistons. I would expect to see about 180 on a warm motor with 10 to 1 pistons and stock or moderate cams. Advancing the intake cam - closing it earlier, will lengthen the compression stroke and produce higher numbers.
 
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Discussion Starter #7
I agree with VintageMilano that those are good numbers for a dry compression test on a motor with stock pistons. I would expect to see about 180 on a warm motor with 10 to 1 pistons and stock or moderate cams. Advancing the intake cam - closing it earlier, will lengthen the compression stroke and produce higher numbers.
Thanks for the tip. So I should have no worries about my engine being roasted from the gas in the oil then, correct?
 

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You should be OK if your oil pressure is normal with undiluted oil.
 
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