Visit The Dirt Forum for More Information

Author Topic:   no compression on a fresh sbc350
dragonfly
Member
posted July 26, 2003 12:54 PM
ok i tech ? i just rebuild a sbc 350 with double hump heads, i put 11:5:1 pistons. well with the 64cc heads its 11:5:1 i checked the compression before actually fire the engine. it was around 180 psi, and now i finally got all my stuff installed and ready to start it. did another compression test and all the cylinders are below 100 psi ., is this at all common ? any help appreciated thnx


jhon hollomon
Member
posted July 26, 2003 01:42 PM
The rings probably haven't seated good yet.


rico 08
Member
posted July 26, 2003 08:42 PM
If you put oil in the cylinders when installing the pistons this will bring up the compression,then after turning over the motor a few times it will go down.Also make sure the carb is wide open,this will lower the readings also.


norightturn
Member
posted July 26, 2003 08:49 PM
that does not sound right. similair motor this year with 10.5:1 , was 170 in dry dock, after break in 175, and after seating pistions with a few laps around the track, 180.

maybe compression tester gone bad?

[This message has been edited by avila (edited July 28, 2003).]

dragonfly
Member
posted July 29, 2003 02:01 PM
Well finally fired engine, ran it about 2 hours, runs great and now carring a steady 189 psi compression on all 8. fires the 112 octane good. sounds great ., gonna finish scaling the car out and see how it does this sat.. thnx


Back to the Archives