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Hey Guys

Buying my first R33

Have owned and drifted a couple of S13's

Just a few questions. firstly the compression results of the motor im looking at getting in the R33 returned results of 140psi even

coming from drifting CA18DET's and SR20's this result seemed low to me but the owner reassured me this is a brilliant result for a rb25 and the compression is lower in a six cylinder, can anyone confirm this?

Steve

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The compression is fine as long as its 140psi consistently. For example 140,140,70,140,140,140 would be bad.

I recently bought a 33 too, and mine were all between 140 and 145. Apparently this was good.

Edited by beamstas
Hey Guys

Buying my first R33

Have owned and drifted a couple of S13's

Just a few questions. firstly the compression results of the motor im looking at getting in the R33 returned results of 140psi even

coming from drifting CA18DET's and SR20's this result seemed low to me but the owner reassured me this is a brilliant result for a rb25 and the compression is lower in a six cylinder, can anyone confirm this?

Hi,

No (the compression is not automatically lower in a 6-cylinder).

However, I believe 140psi on a standard compression test is a little on the low side.

The RB26 service manual lists:

171psi standard (this is what it should be)

128psi lowest acceptable value (fix if below this)

14psi maximum variance across all cylinders (fix if more than this).

When I last tested mine they were 165psi +-1 psi across all cylinders.

If you can dig up the relevant manual for your car you will know what the result _should_ be; I suspect it will be similar to the above.

Hope this helps.

Regards,

Saliya

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