compression test

[antilag]

just gonna do won on my car wat should they b ruffly wats good and wats not?????????????

 

[antilag]

for left to rite i got

145psi 130psi 130psi 150psi

any help would b aprecited

 

[J-GTi-R]

I think the value range for a healthy engine is 120-140 psi (someone else will confirm I'm sure). They results certainly aren't bad anyway.

 

[antilag]

thats a relief i might get a few more pod runs in then providing your rite lol

 

[Fast Guy]

Compression Pressure

Standard 164psi
Minimum 135psi
Differential limit between cylinders 14psi

You're just out of limits. Do you have low compression pistons or thicker head gasket? If you do, you should be ok.
I'd be tempted to get a leakdown test done, just to check if there's any problems and if not forget about it. If you're on standard internals, you;d get abit more power from a rebuild brining the compression back up.

 

[chrisniss91]

How do you do a compression test

 

[antilag]

cheers for depressing me fast guy spose its getting close to rebuild time the engine is completely standard

 

[antilag]

chris its like a boost gauge u screw into where the sparg plug should b and crank over on each cylinder basically

 

[AJ4]

I think its more important to get the same readings across all four cylinders rather than what the actual figure is ( unless its really low ), ie how close they are to one another. Your guage might not be the up to spec and give a comletely wrong true reading, but at least it will have the same error on all 4 cylinders so will give a good comparison.

 

[Fast Guy]

Your guage might not be the up to spec and give a comletely wrong true reading, but at least it will have the same error on all 4 cylinders so will give a good comparison.

True, but unfortunately he's over 14psi down on one cylinder. If it's running fine, I'd be tempted to save for the rebuild and just run it til I had the money.

 

[ashills]

before i took mine apart for the rebuild i did a comp test to see how it was and it they were all between 140 and 154 and i had a crackedring land on one piston ( if i remember that one was a few psi down)

 

[MarkTurbo]

Did a compression test just before christmas and got:

160,158,160,159

The engines done 118,000 miles too, so i was well happy with those results 8)

 

[blr123]

Compression Pressure

Standard 164psi
Minimum 135psi
Differential limit between cylinders 14psi

You're just out of limits. Do you have low compression pistons or thicker head gasket? If you do, you should be ok.
I'd be tempted to get a leakdown test done, just to check if there's any problems and if not forget about it. If you're on standard internals, you;d get abit more power from a rebuild brining the compression back up.

Sooooo.............I've been told 8bar is spot on perfect...........that isn't rite then :?:

Cheers Bryan

 

[antilag]

bry thats like 120 130 psi :?

 

[memski]

Should be more like 10bar, main thing is that they're similar figures.

 

[antilag]

so 25 psi on all cylinders is fine memski if so i have a cheap mod we can do to yours have u been banned from the forum for a week u ent been about pal :roll:

 

[memski]

150psi on all cylinders is the factory figure iirc.

No not been banned mate :lol: , don't have a phone line at my place yet, only ever online when I visit my folks

 

[GINGA]

Its probably nothing but the fact that cylinder 2 and 3 have slightly lower compression could indicate a blown head hasket between those cylinder, combined with the fact your cooling system seems to be pressurising to it don't look good
With the cooling system filled and the rad cap removed and the engine running do you get alot of bubbles coming up :?:

 

[Fast Guy]

Compression Pressure

Standard 164psi
Minimum 135psi
Differential limit between cylinders 14psi

You're just out of limits. Do you have low compression pistons or thicker head gasket? If you do, you should be ok.
I'd be tempted to get a leakdown test done, just to check if there's any problems and if not forget about it. If you're on standard internals, you;d get abit more power from a rebuild brining the compression back up.

Sooooo.............I've been told 8bar is spot on perfect...........that isn't rite then :?:

Cheers Bryan

That's what the manual states, so that will be on standard compression ratio. As long as your figures are fairly even the car should run ok, it's just that you'll be loosing power with less compression. 8bar is a little low I think. Only about 116psi.

 

[Davey]

lol,just face it dave, your car is fooked!
Never mind, like you always say, its only a shiter anyway
loser