225
.060 over
Oregon cam #125
7.8: 1 c/r

I have done 500mi oil change and valve adjust
And I just hit 1180mi decided to do a compression test to see where I'm at. All plugs look good. #1 seemed a little more lean then the rest, which I expect with the longer intake runner, but #6 seemed normal.

#1 134
#2 133
#3 132
#4 130
#5 129
#6 131

This was checked while hot after a 15 mIn drIve. I'm guessing as motor cooled each cylinder dropped a point or 2? Whole process took me a good 30min. Or is that not a significant amount of time to cool and drop #s

Motor runs great little shakey when cold I'm gonna try to change out carb gaskets I think I'm getting a small intake leak from there. Only complaint is I think the damn oil pan leaks only on the very rear half where it bolts to the main seal cap. Or it could be the main seal it self. It's not pouring but definitely gets the rear of the pan/trans/dust cover wet and marks it's spot.

Compression figures always make me scratch my head. I imagine that the raw number is never as important as the consistency, but your numbers are lower than my Slant has, by about 20 psi. Of course it isn't like anyone has a calibration check on a compression gauge. I wonder what thoughts other folks have...

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Slanted D150

I was expecting 150ish numbers. Could it be rings are still seating, or low compression ratio has something to do with it?

Only a 5psi spread? I can't remember working on a slant with such even compression results. Minor cylinder to cylinder comp ratio or ring sealing variations can easily account for 5psi. (it's usually much newer/modern eng with only 2-3% cyl leakdown that have such even comp results)

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63 Valiant Wagon
225 - 4 bbl

I'll take it 5psi spread is good then

150ish numbers are what I would think would be expected. Probably a break-in sort of thing. My 70K miles slant sports 160ish except for one outlier at 110...I consider it a 5 1/2 cylinder motor. It would interesting to plot compression every 500 miles or so on the break in period...

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Slanted D150

Cam centerline and specs will have a big effect on cranking psi numbers. Those look fine to me for that comp ratio, although they could be higher if the cam were in a different spot. 5psi variation is very good.

Lou

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