Compression test figures
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
Not too bad, if you've got a high mileage, stock 350 engine in your car. There's some ring wear, but no broken rings. It probably blows a little oil smoke when you start it up....OK after it gets warm. {P.S. I really don't know much about cars....but I did sleep at a Holiday Inn Express last night.}
Thread Starter
Instructor
Joined: May 2005
Posts: 222
Likes: 0
Thanks. Yes, some smoke. Wondering where it is coming from. Some oil fouling on plugs (all). PCV is set up correctly, not seeing any smoke out breather. Heads are rebuilt Dart ss which I put on not long ago.
Instructor
Joined: Jun 2006
Posts: 123
Likes: 0
From: Westminster MD
Cyl#1 195, Cyl#3=190, Cyl#5=180, Cyl#7=190,
Cyl#2=180, Cyl#4=185, Cyl#6=175, Cyl#8=190
A bit higher, I have a LT-1 engine from a 1970 Z28 Camaro. I'm going to re-adjust the valve lash on cylinder 6 and see if it gets any better.
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
Well within high, low limits. The tune up section of my Chilton's says if the high pressure is 170 the low can be as low as 127.
I like them within 10%. My stock GM block was so far off from square and uniform from the factory I could see where the rings and valves could be perfectly sealed and you could easily be as far off as yours are.
I like them within 10%. My stock GM block was so far off from square and uniform from the factory I could see where the rings and valves could be perfectly sealed and you could easily be as far off as yours are.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
In addition to what the others said ... leaking intake gasket(s) / valve stem seal(s) nicked by burr on lock groove when valve pushed through seal during assembly / valve stem-guide wear / stem-to-guide clearance too much when assembled. FYI: Posi-type vss easily nicked by burr; others much more robust.
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