Compression Test Results

[Harry-Hotpants]

just after what figure i should be expecting from my rb25 when doing a static compression test. i got even 155-160psi across all cylinders whilst cold. let me kno what u'v gotten from experience

cheers

[wht510]

Sounds pretty good. My old RB20DET (red top NICS) with 200K on the clock had an even 120psi across all 6 cylinders.

I think if they are all even you should be laughing.

[Ultimategtr]

Not bad at all, considering factory oem is around 170psi.

Mine was around 165 across all 6 when i first got mine @ 76000k's

[Harry-Hotpants]

ok cool well i kno 160 is pretty good for a nissan turbo etc but iv been told a few times that the rb25 is a "high compression" turbo motorso just checking that all is good

cheers

[_Ryan_]

that is good, also aslong as they are all within 5-10psi of each other then dont stress, if it was 160 160 140 90 150 160 then you would be doing some further investigating...

[RaZ_TuRbO]

For reference my rb25det got 162,164,160,162,162,164 apparently 89,000kms engine.

[SiR_RB]

sorry to change the subject, but what would be the minium for an Rb26dett - stock standard internals ??

[Moodles2]

121psi is the absolute bottom limit for the r32 rb26dett, the service manual hints at a complete rebuild

[slr7000]

i got 120 115 130 110 115 110 on my rb25det, apparently it was rebuilt with forged pistons in it like 2000kms ago, should i be conserned?

[Sydneykid]

i got 120 115 130 110 115 110 on my rb25det, apparently it was rebuilt with forged pistons in it like 2000kms ago, should i be conserned?

Depends on what compression ratio it was built with how good the starter motor is and how much grunt the battery has. That's why a leak down test is always better and in your case warrented by the 20 psi difference (130 - 110).

Cheers

Gary

[180or200]

hey guys

sold my old turbo gt3076 to a mate with a rb25det, on my car it pulled hard 3500-3800, on his car it's a real slug even with the addition of a 6boost manifold

doesnt pull hard till 4500, could this be related to a low compression motor? motor is supossed to be a built motor but cant find any specs on whats inside it!

another interesting thing is it takes alot more timing than any other 25 i've tuned.

Old turbo which we thought was stock and stuffed turned out to be a mint gcg highflow almost brand new, that would only hit 12 psi by 4000,

[Jmaac]

check ic piping, vaccum hoses, wastegates etc.