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Rb25 Turbo On A 20


trxbal
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I've done three of them and they've always bolted straight up, oil and water lines all match up fine. Try find one with the compressor elbow that has the vacuum nipple coming off it factory, I'm fairly sure they come off the R34 turbos

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what do you mean no power gain?

RB25 turbo at the same boost the RB20 turbo was set to will produce a fair bit more power.

remember to use the actuator from the RB20 turbo on the RB25 turbo

that way you get 10psi stock instead of the 7psi the RB25 actuator holds.

many years ago, I put a series 1 R33 turbo on an RB20.

with 10.5psi and no tune it made 152rwkw

Also, R33 and R34 turbos are not the same.

R34 turbo has a bigger rear and will be laggier on teh RB20.

Stick to R33 turbo.

just go to an exhaust place, tell them to remove the intercooler piping that goes from the turbo tot he cooler, and tap a nipple to the pipe as close to the turbo as they can.

that is where the vacuum line from the actuator will go.

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If its an original a31 rb20det, the water lines have a different (smaller) banjo bolt. can't remember size, m16 (a31) instead of m18( r32, r33) maybe.

Got caught out when I did this on my first cefiro.

So you can get water lines off a r32 rb20, they will work, or make up custom water feed/return lines.

And yeah, you'll see some gains. worthwhile mod if you need to replace turbo anyway.

Edited by CEF33Y
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