I have a '99 GSR with a JRSC on it and the motor is stock with 73,000 miles on the clock. If I did a compression check on my motor, what kind of #'s should I see for my motor to be considered boost worthy?. I did a compression check on it about 5-6 months ago and saw 195-195-190-195, does this look right to you guys?. The supercharger is tuned with 440cc injectors and a Hondata s200, I plan on taking the charger off in about 3 weeks or so to go the turbo route. I just want to know what kind of comp #'s I should see before I put the turbo on the car.

Thanks.

 

Numbers are nearly identical, looks good

 

I just didn't know if these #'s are unusually low considering when I did a search people are coming up with #'s like 220-230 across the board.

 

the manual says:

250rpm and WOT : nominal 270
minimum : 135
max variation : 28

your numbers are great so dont worry

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rtype11 &raquo;</TD></TR><TR><TD CLASS="quote">the manual says:

250rpm and WOT : nominal 270
minimum : 135
max variation : 28

your numbers are great so dont worry</TD></TR></TABLE>

Are you sure the manual says that? I don't recall the Helms reading that high, and I don't think ANYBODY has ever mentioned 270psi in a cylinder.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by VTC_CiViC &raquo;</TD></TR><TR><TD CLASS="quote">Are you sure the manual says that? I don't recall the Helms reading that high, and I don't think ANYBODY has ever mentioned 270psi in a cylinder.</TD></TR></TABLE>

yes i'M SURE that is also because nobody does the compression test right!

read 250rpm and WOT - wide open throttle! most of you just pull a spark plug and turn the car over on the starter a couple of revs, you will not get 250 rpm

also i used the acura service manual and not helms

 

numbers are good...i have the exact same motor and year...95 usdm gsr...190 across the board!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rtype11 &raquo;</TD></TR><TR><TD CLASS="quote">

yes i'M SURE that is also because nobody does the compression test right!

read 250rpm and WOT - wide open throttle! most of you just pull a spark plug and turn the car over on the starter a couple of revs, you will not get 250 rpm

also i used the acura service manual and not helms</TD></TR></TABLE>

Gee.. that's exactly how I do it, still never seen more than 220-ish psi

 

Thanks for the help people.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by VTC_CiViC &raquo;</TD></TR><TR><TD CLASS="quote">Gee.. that's exactly how I do it, still never seen more than 220-ish psi </TD></TR></TABLE>
thats great dont worry about being at 270, look how large the variation honda allows for compression - 270 to 135, plus there is a difference when car is hot or cold etc.. thousand variables, if you have a daily driven high mileage motor with half an inch of coke on the pistons and dome you might get crazy high numbers also...

 

anything CLOSE to 210 is good IMO. 180 and lower is questionable. 270 and up is well unheard of to me.

 

don't worry about it, if you want to do a leak down test that will give you more info. When I first put my JDM GSR together it made 210-215psi, after 6 months of driving it make 230-235psi. The carbon buildup in the pistons and valves will make the compression higher and valves will seal better, also the # of cranks, type of cams, cam timing, engine temperature, and particular gauge will all make a difference.