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HI GUYS,

i'm trying to sus out the old rb25 turbo onto an rb20 myth

(and no...don't you dare type back with "try searching")

my research has found that it is a straight bolt on in SOME cases with only the elbow a nessecity.

BUT from what i have read..the earlier model r32's need the banjo bolts and waterline as well...or somethnig like this

i want to know exactly who had success with a "straight bolt on" and what yr model (particularly around the 1990 and 1991 yr). because i have a 1990 but suspect this is included in the "early" r32 series and hence i need the turbo + elbow+ water line + banjo bolts = bitch

will also need to know the turbo u used - was it series 1 or two? but this i dun think makes the difference

i just dont want to get caught half way through the operation with a not fitting water line.

please start sharing info brothers and sisters....

thnx

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thanks for searching first mate. You have pretty much found the answer.

SI and SII are the same layout.

I've changed an 89 model ugly poo's turbo before, and it had the new lines and banjos. It would appear that it was a very early 89 model issue where they used different lines and banjos for the waterlines - they were 22 mm instead of 24 mm. I've also done a 90, 91 and 92 and they were all the correct 24mm one.

you're right in your searches.

Edited by MANWHORE

Your information is correct. early r32's run different size banjos on the turbo. You seem to be somewhere in the middle so you could have either to be honest. an 89 is guaranteed to be small banjos, a 92 is big.

An easy check is to measure the head of the banjo bolt on the out side water feed and ask the seller of the 25 turbo to measure the one on their turbo for you. I'd help you out but all my bits are in storage atm.

looks like search does work :)

yeh manwhore and dave...thanks for the fast replies

but as manwhore said...it's not very consistent either. and i have read before somewhere (haha maybe u were the one that wrote it manwhore..haha) that amongst the "early models" they may or may not have the correct size banjos...simple as that

but my gut feeling is that the waterlines were standardized for the 1990 yr onwards...tho i dont know this thru experience.

bhdave: does measuring the size of the head on the banjo of my 32 and comparing it to the head of the r33 banjo really guarantee that their threads will be the same size dia?....i mean its a good call that u have and i'm sure its probably correct...but in the "nuts and bolts" industry in general measuring a head does not guarantee that you can determine the thread size. Tho i think ur right.. in this case its prob safe to say without having to unbolt stuff.

the head on the banjo on the r33 turbos and later model r32 turbos are 24mm. the earlier one is 22 mm.

I know that measuring the head in the nuts and bolts industry doens't garantueepoeoihwwpjeew (spelling spaz) the thread diametre, but i have onyl ever seen the two sizes.

ooo...silly me i just realized that when u talk about the sizes your talking about the size of the head and NOT the thread size. yeh makes sense..24mm is a bit big for a thread size..yeh i shoulda picked up on that earlier....jackass (talking to myself).

ok so next thing..... and this one may seem stupid

can i measure this head of the banjo bolt easily buy putting my head under the bonnet in the turbo direction...maybe by removing the heat shield or something

or do i havta go digging and unbolting to be able to finally measure it..in which case the turbos practically off and i may as well proceed to swap..

perhaps the waterline goes somewhere else and uses the same bolts as at the turbo..these could be an indicator?

what should i be looking for??

...and your comment (1400R) does not help at all...

i'm just trying to establish some guidelines by which rb20 owners can go off if they wanna do a checklist of what to look for pre rb25 turbo-operation.

i'm just tryin to be helpfull because i guarantee you this question will come up again in another month if not before..because even with a few write ups floating around the banjo thing is still not in concrete. I'm tryin to make a little self help thing here by which someone like me reads it and then goes:

"ok i have bought a rb25 turbo - check"

"i have bought the rb25 turbo elbow (or am willing to modify the rb20 one) - check"

"are my banjos gonna be 22's or 24's - yay i have determined that theyr 24's

----> lets go do some bolting at our friends workshop!

so i was just asking politely if the banjos are easy to locate and measure and allow me to go on my merry little way.

yeah mate, you sure can see it very easily. pop the heatshield off - it's 5 bolts. be careful, it's likely that about half of the bolts will snap from the constant hot cold hot cold. be careful when taking them off.

you'll see the oil line on the top - that should be a 17 mm.

the one on the side is the water line - either 22 or 24 mm.

if it's 24, you're in luck. if it's 22, it's not that bad. you can just get the lines, they're cheap, or if you're in a hurry, you can get a braided line from pirtek etc, no biggy!

i just changed mine on the weekend 89 gtst. and fitted fine only thing is you do need the elbow the 32 one is smaller. and i reckon would be a titrat you re-drill... also i couldnt even use the turbo to elbow gasket and hack it to fit the 33 elbow 32 ones are heaps smaller

hey gt-t r34 so you had to make up a new gasket then to go between turbo compressor and elbow???

cos i may be in this situation cos lookin at buying an r33 trubo but without the gasket betwwn the compressor outlet and elbow.

so what did you use??

i'm thinkin of just goin to repco or somethin and seein if they got some metal gasket material. would this work??

just to let you know,mines an 89' model and i have the smaller banjo bolts.

Motorsport connections @ seven hills.(costly but they got what you want)

i was given a modded(drilled out) rb20 elbow with the turbo i bought.

takes a bit of fiddling with the elbow,but you'll get it.

Gasket Goo does miracles by the way.

also i got about 1m of rubber tube because we snapped the old metal line that goes

around the back of the engine(between engine & firewall). The rubber line works fines.

also suggest getting your exhaust manifold checked as they tend to warp from heat.

i.e bolt studs snap inside block.

Dont forget to top up your water before driving again.

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