feeback on compression test results

[falcon fanatic]

Hi,
Just looking for opinions on these compression test numbers. Want to swap in a cam, just making sure engine is otherwise healthy.

155, 175, 170, 165, 175, 160.

These are "wet", that is with a bit of oil in the cylinders. did a dry test, too. Numbers where about 5 to 10 PSI lower on the dry, but no one cylinder stood out as being grossly lower on the dry than the wet tests. That #1 strikes me as oddly low.

 

[powerband]

Hi,
Just looking for opinions on these compression test numbers. Want to swap in a cam, just making sure engine is otherwise healthy.

155, 175, 170, 165, 175, 160.

These are "wet", that is with a bit of oil in the cylinders. did a dry test, too. Numbers where about 5 to 10 PSI lower on the dry, but no one cylinder stood out as being grossly lower on the dry than the wet tests. That #1 strikes me as oddly low.

Take this as opinion - The spread is long end of "healthy" and as long as no smoke on decel is evident, is likely to live a long happy life. #1 and front cyl's tend to have valve guide problems . ( longer oil delivery when cold? - ) . To really determine health, the Oil Pressure difference between Cold and Hot on a mechanical guage is reliable.

You'll need to pull the head for Cam swap and long as it's off ... Carb(s)?, Headers?, Head need work? ...

( Is it possible to swap cam W/O removing head?, maybe if you turn it upside down the lifters wouldn't fall out? )

Have Fun...

Performance built Ford 250 Six Engine - 10:1 Pistons, Clifford Balanced Rods, Clifford 272H Cam, Line Bored & Balanced Bottom End, Torque Plate Machined - .070 Overbore, Cloyes Timing Set, Melling Oil Pump, Fisher Balancer, 1.88 int. Valves, Ported and Relieved, Offy 3X1 w/3 Holleys, Hooker Dual Out Longtube Headers, Re-Curved Distrib., Lightened FW, Centerforce Clutch, the works, a few mysteries...

 

[falcon fanatic]

Thanks. that's what i figured. Head was totally done a year ago, including porting, big valves and log modification. Still not happy with the power, tearing in again to get that little extra bit.

 

[falcon fanatic]

Just ordered 264/274 - 12* cam, lifters, roller timing chain & cam degree kit. Woo hoo! 8) 8) 8) there's no turning bck now. Hope those cam bearings hold up :roll: