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Compression Test Results

Harry-Hotpants
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Sydneykid Grand Master

Sydneykid

Posted
Posted
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 Proficient

180or200

Posted
Posted

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,

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