Compression #'s on B18B1
 

I just did a compression test on my motor and came up with these #'s: 160, 150, 150, 165
Based on the other numbers I've seen posted on the board, they seem a bit low. Any ideas to why?
The motor has 140k - Time for an overhaul?

Re: Compression #'s on B18B1 (sdinteg)
 

as long as they are all close you'd be fine. I would do a leakdown test though.

Chris

Re: Compression #'s on B18B1 (sdinteg)
 

it could be time for an overhaul. but consider this bro; comp #'s are also affected by engine comp ration. your b18b1 came with 9.2 to 1. this means that your numbers will naturally be a little lower then say a gst or b16. id look at other ls comp checks to see how they came out. this way youll know what a good condition motor puts out. then youll have a base for your own numbers. peace!

Re: Compression #'s on B18B1 (BigHeadKid)
 

Compression tests suck ass.

Its too standard on this website to rely solely on compression readings. Compression is a really horrible test to tell you that your motor is fucked or not. (for the most part)

Do a leakdown test. It tells you loads more than compression. Bent valves, Blown HG, Washed/Damaged rings.

-s

Re: Compression #'s on B18B1 (sander)
 

true. but a comp check is just a start though.

Re: Compression #'s on B18B1 (BigHeadKid)
 

Geez, I gotta paste this somewhere so I don't have to write it 400 more times...

Compression #s depend on lots of things.
1 - Internal volume of the gauge (including extension hose).
2 - Where's the check-valve located inside the gauge.
3 - Oil temperature & viscosity.
4 - Starter RPM.
5 - Throttle (should be WOT).
6 - Engine (CR & cams).

Don't compare actual #s unless all that stuff is the same. You can't just say 'it's a stock LS' & ignore all those other things...

Re: Compression #'s on B18B1 (JimBlake)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JimBlake &raquo;</TD></TR><TR><TD CLASS="quote">Geez, I gotta paste this somewhere so I don't have to write it 400 more times...

Compression #s depend on lots of things.
1 - Internal volume of the gauge (including extension hose).
2 - Where's the check-valve located inside the gauge.
3 - Oil temperature & viscosity.
4 - Starter RPM.
5 - Throttle (should be WOT).
6 - Engine (CR & cams).

Don't compare actual #s unless all that stuff is the same. You can't just say 'it's a stock LS' & ignore all those other things...
</TD></TR></TABLE>

And people ask me why they suck for comparison purposes.

-s