I installed Buddy Club Spec4 cams in my B18C ( stock block and head). with P30 pistons .....

prior to installing these cams i did a compression test and i got almost 260 (unless the compression tester is broken) but i tested it again today and i got 190, 200, 190 and 200.

The guy i was by told me that Cams affect the compression ratio due to the higher lift. Is this True?

what is the general figure for P30 pistons in a B18C .

Also what can i do to increase my low end power, the car feels some what slower ib4 VTEC.

 

jesus...we need a little more information to even come close to giving a rational opinion or helpful insight.

you just said the block is stock but then you say that it has p30 pistons. were the valve stems, seals, rings, etc. replaced....is the car tuned...how long have you been driving with these cams....how hard have you been driving it.

was it hot when you did your first compression test? was the test done at wide open throttle?

 

the first test was done on the car fairly warm. stok block meaning it hasnt be milled or anything .

yes they were both done att Wide open throttle.

onlything replaced in the head was the Cams and Valve springs .

 

Aggressive cams can/will lower the dynamic compression ratio.

As for your power issue, what sort of tuning has been done on the setup?

 

like padawan stated give us some more info, they will lower the dynamic compression which is why really aggressive cams need to be supported be high compression to really "benefit" from them.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Padawan &raquo;</TD></TR><TR><TD CLASS="quote">Aggressive cams can/will lower the dynamic compression ratio.

As for your power issue, what sort of tuning has been done on the setup? </TD></TR></TABLE>

We did a Road tune with the PLX wideband and Hondata S300.

The block is a B18C block with P30 pistons, GSR head with Buddy Club P1 dual valve springs. Spec 4 cams and 0.5 mm head gasket.

B4 the tune the car was running almos 16+ AFR in some areas or the RPM range and 9.9-10.2 in other areads, on the wideband. After tuning we got it around 13.8-14.7 straight across.
Tues night my timing belt tensioner gave up on me and cause me to bend some valves. i got on the the phone today and ordered in some OMNI power high comp valves.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Padawan &raquo;</TD></TR><TR><TD CLASS="quote">Aggressive cams can/will lower the dynamic compression ratio.

As for your power issue, what sort of tuning has been done on the setup? </TD></TR></TABLE>

This is true. They typically keep the intake valve open longer after BCD. So for a longer part of the compression stroke, air/fuel mix is actually bled back into the intake manifold.

 

cams don't affect compression ratio but cams may affect compression pressure....you have less compression pressure because you have more overlap