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Rb25 Turbo Onto Rb20det


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am thinking of purachsing an rb25 turbo from a series 2 R33 (apparently with the nylon compressor wheel)...

EXACTLY what would i need to make this fit onto my rb20?

eg oil/water lines? any other things?

also, what markings would this turbo have on it to ensure i am getting a series 2 turbo and not getting ripped off?

And.. when i get the turbo, should i get it checked out, or just get it bolted on?

finally, how much would labour be you think?

cheers,

Warren

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http://www.skylinesaustralia.com/forums/in...howtopic=109532

this is the turbo.. (pics there)

it says 45v2 does that sound like one with the nylon compressor to you?

can someone elaborate?

its a little more $ than a standard rb25 one, but if its got the nylon wheel then i would pay it..

PS i did search and nothing concrete about what to use..

thanks gordon for the link!

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also add the costs of new trubo/manifold and turbo/exhaust gaskets..

i would upgrade to a split dump at the same time if you have the cash.. they make a fair bit of difference. (if you havent already)

new copper gaskets on the banjo bolts are a good idea too.

might not hurt to get someone to check the turbo too (couple of places so they dont try to talk you into a rebuild), just so you know your getting what you payed for..

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gaskets cost about $30 I think.

install should cost about $250-$300

don't forget to use the actuator off the stock RB20 turbo on the new turbo.

gives you 10 psi whout boost conrtoller as the stock one does.

oh..

other than the Elbow off the turbo, you will also have to drill and tap a nipple on to the compressor cover or intercooler pipe for the wastegate hose.

to drill the comp cover, you will need to take it off the turbo.

I guess same goes for intercooler pipe.

Edited by GTST
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Personally I have no idea - all I know is as the seller of the turbo, a) it is in very good condition, and was inspected by Bill at Adelaide Turbo Services, and b) I got reamed by SAU member Hooman who I bought this off from as a "R34 Neo turbo" and paid $650 for it.

Brendan :thumbsup:

Edited by Tangles
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no no.... it's a good price.

just saying that on the RB25, there is a boost controller solenoid.

the hose goes from the intercooler pipe to the solenoide then through to the wastegate actuator.

on the rb20, the wastegate spring controlls the boost. it reaches about 10psi in stock form.

so there is no other controller so the vacuum hose goes from actuator to the compressor cover.

so to use this on the rb20, you need to drill and tap a nipple on to the compressor cover like in the rb20 turbo or drill and tap a nipple on the intercooler pipe like in the rb25.

I think you didn't sell him the ELBOW pipe (refers to the first part of the intercooler pipe) which is needed.

If you don't get that, you have to use the rb20 one and to do so, you have to drill out the 3 holes very close to the edges to make it match the larger rb25 opening.

when you use the rb20 actuator, on the rb25 turbo, you still run 10 psi through it.

and considering it is a larger turbo, it flows 25% more air at 10psi than the stock turbo at 10psi.

WARREN - use your boost controller anyway. it will help bring boost on quicker.

12 psi through the rb25 turbo is what I ran on my last car.

well it would drop to 11psi towards redline anyway. but I forgot to use the rb20 actuator so the bleed valve was making it boost fro the 7psi stock to 12psi..

I will be using 14psi through rb25 turbo for my current car.

when I buy it and install it that is.

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GTST - as always, great advice.. thanks

so do you think its worth finding hte rb25 "elbow pipe" before i fit this, or just modifying the rb20 one?

keeping in mind that i will be taing this to a workshop and saying "do what you need to make it fit"

i'm thinkin of going to mercury motorsport so they know their skylines backwards and have probably done this uprade a few times...

that way if they need to get gaskets they can organise all that jazz, and whatever needs to be modified is done by them and added onto the price

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CHECK THE WATERLINES!!!!

I can't believe there are all these responses and no one thought to ask whether it was an early or late r32.

Late rb20 has the same size banjos as the rb25, Early rb20 does not. You may need custom lines for it.

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