dirtySOHC's

after doing a compression test today i found out some different results than any other time. usually when i do my compression checks my numbers read as follows (from #1 cylinder to #4) 180 180 180 185. well i been running a 65 shot wet on my y8 for a few weeks now and i decided to do a compression check today and the results read back as 175 179 175 180. now i know these numbers are still within the limit but the sudden change in compression.......wat does this indicate??

wat do you guys think?

SloVXHatch

It means that you should stop using the NAWS because eventually 175 179 175 180 will turn into 100 140 175 130.

dirtySOHC's

wtf???? ok buddy.......put a lil more thought into your replys.

EDT: nevermind i checked you out and your just an uneducated newbie "please please PLEASE dont flame me" y0 hahaha funny ****




[Modified by dirtySOHC's, 7:29 AM 6/10/2002]

Kamin

was the engine fully warm?
throttle all the way down?

dirtySOHC's

throttle was all the way down........took to the car out to the corner store then did it when i got back......i was thinkin maybe it wasnt wamr enough but *shrugs*

ill do one agian tomorrow after i know i ran it for a while.

97hb

Put a couple drops of oil in the cyl. and if the compression test reads higher than before the oil, you have bad rings.

dirtySOHC's

ill give that a try too........

k_spek

How often do you squeeze?

dirtySOHC's

i may go through a 10lb bottle in about 2-3 weeks. i dont really pay attention i just know i dont spray like crazy. i dont spray at every light i see and every person that wants to rev on me.

when i get back to my crib i always pull the plugs to check them after i know i just sprayed..........they look normal.


[Modified by dirtySOHC's, 12:07 PM 6/10/2002]

Mista Bone

after 24-25 bottles I was at 180-175-175-180

after the last bottle I was at 180-175-20-180

ZEX kit?
Make sure to use the 75 hp (#32) fuel jet and never spray when bottle pressure is above 900-925 psi.

dirtySOHC's

its a NOS kit. i heard about your car but you were pushing an 85 shot so you would expect that mishap sooner or later.

i just hope that the lil change in compression is not a result of engine failure bond to happen

M.A.R.C.

damn urs was so low? i did mine the other day and i got like 260 across the board

dirtySOHC's

wat do you mean.....my results are all within the limit to wat it should be reading. wat the hell are you running to have such high comp results?

dirtySOHC's

aight today i did another compression test and i made sure the car was fully at operational temp. resluts read back as 170 170 170 180.....wat is goin on here?


[Modified by dirtySOHC's, 7:01 AM 6/11/2002]

Spike2

probably b/c it burned all the carbon crap off your dirty old *** pistons

dirtySOHC's

also i did some test runs. when i sprayed i started to hear my car detonating at 5500 rpm or whenever vtec engaged. after the first test run i took my car back home pulled the plugs and the metallic flakes were present. so then i made some adjustments. i put my fuel psi to 40 with hose attached, and retarded my timing about another degree (which was already 2 degrees retarded), and i regapped my plugs to manu. specs (was at .035 in.). took it out agian and when i sprayed same thing happened.......the infamous detonation knock

the only other thing i can think of changin is gettin another step colder plug. 6-7 and imma also switch out to a 50 shot jet.

after that run is when i did the second compression test and read 170 170 170 180.

Plan B

My bottle pressure was over 1300 psi, and I burned up 2 exhaust valves. I still ran a 10.4 1/8th mile only on the inertia of 1st gear. Car shut off after that.

Halo

I have 260 across the board with 4.2 cc JE's. I say your numbers are totally normal, a slight variance like yours is to be expected from any motor. I am sure when I rack up some more miles on my motor(crvtec), the numbers will change also

dirtySOHC's

yah i know its still within the tlimits but i was just worried about the sudden change in compression then to find out im detonating.......

laughinxxx

I'm agreeing with Halo on this one. I doubt that you have a problem. The guys at honda told me that a bit of difference in compression numbers is normal. Do the compression check with the oil and see if you get higher numbers than you do without the oil. You shouldn't have a problem unless you are detonating, which you know you can check your plugs for.

evolution_sfv

I bought my car with an 80 shot NOS system, directly ported to the intake manifold. I did my compression check, and it was at 160-165-175-160. Its either because the cylinder walls were scored (i ran off the TB for 2 months cuz i got jacked for my CAI) or piston rings arent as good.

Halo

someone jacked your cai? that is so ghetto, i really hate thieves

97hb

I have heard the knock. Not good. Knocking for 3 sec. and now I have the biggest paper weight in the world(maybe theres one bigger)

Mista Bone

WTF are you guys smoking???????


I've never heard the "knock".........even made one pass on the ZEX at 85 shot with NO extra fuel!!!!!!! The vacuumline blew off the FPR, but she never knocked! Ran a 13.5 at that! Ground straps on the plugs were purple though!

dirtySOHC's

then i dont know wat im hearing but its some kinda knock.

on the plugs can you distinguish between carbon and the metallic flakes caused by detonation......??????