I decided to get a compression test done on the motor before i put it in the shop in 2 weeks for some head work and this is what i found.



Its leaking oil bad so right now im hoping its just the head gasket, but tomorrow i should be taking it back to get some more test done so I can know for sure. Either way I guess im just gonna use this opportunity to raise my compression while I get the head work done, just more money to come out my pocket.

 

ouch, number 3 is hurt'n.

 

I could never figure out why the engine runs so damn hot theses days but now i see.

 

any feed back?

 

mileage?
how hard u drive it?
cooling system problems?

looks to be a head gasket since u got low compression next to each other that usually means head gasket

if like 1 and 4 were low and 2 and 3 were good then it wouldnt really look like a HG

 

i have never seen a gsr or for that matter even a itr motor have 260psi before. do you have up compression or is this a stock motor?

 

260 is pretty standard on a higher mileage car.

 

yea its a bone stock JDM GSR. so im gonna replace it wit a 2 layer

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by C-speed Ricer &raquo;</TD></TR><TR><TD CLASS="quote">260 is pretty standard on a higher mileage car. </TD></TR></TABLE>

thats interesting..do you have an explaination for that?

 

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

thats interesting..do you have an explaination for that?</TD></TR></TABLE>

seriously

 

maybe those are zeros that didnt get connected lol

 

So the older your motor, the more power?

 

Sorry to hi-jack, but what would be good compression numbers for a 92LS with 200,000 on it? What should it be at if it was brand new?

Thanks :D

 

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

thats interesting..do you have an explaination for that?</TD></TR></TABLE>

Please dont quote me on this, this is just something i read somewhere, but i forgot where...anyways, i think he means higher mileage cars have higher compression because over time, there is carbon deposit build up inside, which would mean compression would go up. But again, this is something i read so please dont quote me on this

 

like around 180 all around for brand new

 

took the car back to the shop today and found out that its leaking oil from cylender #3 and 4 which explains the low compression in them. So now i have to wait till i put in the shop and they take it apart before i know what i got to do besides replace the head gasket, but it looks like at worst im going to rebuild the block wit over sized pistons

 

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

Please dont quote me on this, this is just something i read somewhere, but i forgot where...anyways, i think he means higher mileage cars have higher compression because over time, there is carbon deposit build up inside, which would mean compression would go up. But again, this is something i read so please dont quote me on this</TD></TR></TABLE>


true carbon build up does raise compression, im a smog tech and when cars fail for nox one of the things that they will end up having to do is flush the engine out seafoam etc.

carbon artificaly raise's compression when u raise compression theres more heat

when u get more heat u get more nox, (nox is created by combustion temps 2500degrees and higher)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Ba4 &raquo;</TD></TR><TR><TD CLASS="quote">true carbon build up does raise compression, im a smog tech and when cars fail for nox one of the things that they will end up having to do is flush the engine out seafoam etc.

carbon artificaly raise's compression when u raise compression theres more heat

when u get more heat u get more nox, (nox is created by combustion temps 2500degrees and higher)</TD></TR></TABLE>

so will the car be faster with this higher compression from the build up?

 

with bad compression like that, do u always notice a performance loss?

 

my car is in the shop now, it turned out that i have 4 bent exhaust vales in the low compression cylenders

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BLK99VTECR &raquo;</TD></TR><TR><TD CLASS="quote">my car is in the shop now, it turned out that i have 4 bent exhaust vales in the low compression cylenders</TD></TR></TABLE>

have you found the reason for the oil leak though? just curious

 

they said probally the cam seals. I bought a whole gasket kit so they gonna replace all the gaskets and it should take care of that.

 

the swap i bought came with compression like like

#1-215 #2-100 #3-150 #4- 215

bone stock usdm gsr with 60k

sent that **** back and got a refund!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99exd16y8 &raquo;</TD></TR><TR><TD CLASS="quote">the swap i bought came with compression like like

#1-215 #2-100 #3-150 #4- 215

bone stock usdm gsr with 60k

sent that **** back and got a refund!</TD></TR></TABLE>

I wonder what the issue was with that motor

 

260 is average......hahahhahahahahahhahahahaha. Carbon will naturally flake off when it gets to a certain thickness. Basically anywhere from 1000 miles on the motor will have pretty much the same amount of carbon build up. Yes, I have taken my head back off after 500 miles and the **** was covered in carbon buildup. On top of that, carbon buildup isnt effecting anybodys motor by that much.