Ok my friend did a compression test on his C5 and its way off...
with plugs in he got, 165, 127, 135, 165

the motor runs fine, no problems whatsoever,,, however the motor is boosted, he is runing JRSC at 8PSI and the car pulls hard... dosent smoke or anything!

is this serious? what do you guys think the problem is? valve seal, head gasket?

thanks

 

Sounds like there might be a problem, I would re-check the #s with a different gauge.
Is there any internal work/ mod to the motor?

 

with the plugs in?

was this done with the motor warm and at WOT?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RTW DC2 &raquo;</TD></TR><TR><TD CLASS="quote">with the plugs in?

was this done with the motor warm and at WOT?</TD></TR></TABLE>

What he said plus add 2-3 drops of oil in each cylinder and re-check. if the numbers jump up you have bad rings.
how long has he been using the supercharger? 8 psi is a little much for a r without tuning. does he have stock injectors, ecu, fuel pump?

 

definitely re-check the numbers, as stated above.

a leakdown test probably wouldn't hurt either...

 

car is tuned with hondata and put down 240WHP...

so leak down test would be better right?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ATgrills.com &raquo;</TD></TR><TR><TD CLASS="quote">

so leak down test would be better right?</TD></TR></TABLE>

yes....thats a good place to start right now! Somethings wrong if your #'s were that inconsistent.

 

yea leak down would b better.also try a wet compression test..squirt some oil in each cylinder..