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Hey fellas,

I figured hundreds of pics of these two turbos have been posted on this website, but not in the one thread.

Can someone with both turbos post a pic of them side-by-side, with indications of ways to tell if you have one

or the other.

If no-one bothers, I might source pics of the forums and post them up here myself. Might be hard to work

out the difference!

Thanks,

Adrian.

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https://www.sau.com.au/forums/topic/108640-rb20-and-rb25-turbo-pictures/
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The wastegate isn't giant.. its the same size as the rb20 one, which you can see in the background. Thats one of the earliest RB20 ones (1989 model) so i think is a bit smaller.

They're not so identical.. the differences are more subtle visually.

1. Such as the point for the wastegate directly on the housing (mind you this is on the rb25 turbo, just hasn't been tapped out from factory).

2. The exhaust housing looks a bit fatter on the rb25

3. The inlet port is smaller and I think a little bit longer on RB20

And of course they have different markings. To the eye it seems more obvious I think.

Its a bit hard to tell when both are fitted and everything such as heatshield, etc is covering it up though.

yeah.. the rb25 ones have like 45vX where X = version number.. The rb20 I think are 16V

Its all covered somewhere you know :) You tend to forget things and think "oh it'll be on SAU if i need to find it" :)

Thanks buddy, I'll check it out.

Top work GTST. Can you post up the actual measurements you got on those impellers?

If they are still apart, then try to get the size of the inducer (smaller end) of the compressor as well. This will allow us to calculate the trim size.

cheers

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