Rb20det compression results

[Timd]

Im currently considerig buying another rb20, the compression results the seller gave me are as follws...

1-130

2-135

3-130

4-130

5-130

6-135

Is it just me or are these numbers a bit low. Im not worried about the difference seen in no2 and 6. I just thought a healthy engine should show compression of maybe 150 - 160? Although seller assures me these number are spot on? test was done on a warm engine

Thanks for your time, Tim

[88silhouette]

i have a 1989 rb20det eccs in my HR31 Gts-x

did compression test the other week. the engine is stock, runs normal boost, and runs beautifully. ran 135 on all 6.

my other mates' rb20det silvertop is bout 113 on all 6 and it's unhealthy.

[predator]

That's very close to what both my RB20's tested at recently..

My gauge has always read low, and seems to read 130psi on a healthy engine. So I wouldn't be too worried.

As long as they are within 10% everything should be fairly fine.

[Timd]

Thanks for your reply lads, anyone know what compression readings would be on a new rb20?

[predator]

They're meant to be 170 (or is it 178psi?) from what I can remember. It's on here somewhere.

[raz0r$harP.UK]

my rb20det with 160 kms on the car had it around 150 to 160 with most on 155

but apparently the engine was rebuilt bout 30thousand kms ago

but i remember somewhere it doesnt really matter as long as there isnt a big difference between the cylinders

might not be a bad idea to pay to get it tested by a mechanic you know

[siksII]

those figures are fine, it is the difference that matters, not the outright figures, as various factors(inc how hot the motor is, battery voltage and also the gauge) can make the outright figures incorrect.

[MerlinTheHapyPig]

yeah, as long as no huge difference, then it's probably ok, does the engine run smoothly etc?

dont' rebuild/replace just coz of a low compression

from memory, i got 152psi +/- ~2psi

[Timd]

Im going to rebuild my current engine. Ive decided to get a second engine so i can take my time and do it properly. That being said, i still dont want a bodgy replacement motor

I wish i was a patient person, cant stand not being able to drive the thing.

[MerlinTheHapyPig]

just to elaborate on what i just said th ough, a comrpession test won't pick up everything

i've comp tested ca18det's which were piston slapping pieces of crap and they pulled 165-170psi all round

i've also tested an ex-drifted sr20 which got 165psi but engine ran nice and smoothly, just had been driven on rev-limiter for most of it's life...

[nemz]

where can i get ma compression checked?

[88silhouette]

leon g'day mate my case of vb and my housemate Alan will do a compression check for you.

we live near liverpool

[heaveyfoot_ skyliner]

before you start the test do you have to disconnect the electricals like ignition module etc ?