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my mate used my turbo off my blown 25 on his 20.

If you do it and you dont have a aftermarket boost controller yet, swap your rb20 actuator onto the rb25 turbo as it oppens at 8-10 psi instead off 7. Just a little bit more performance for nothing!

I'm in 2 minds... I said that so he doesn't hold back a sale.

I don't think it has the elbow pipe anyway but you can ask..

I'd like it, but I'm in the middle of selling property and can't play with cars right now really.

Wife will have my balls if I do..

and not in a good way

Edited by GTST
  • 3 weeks later...

I have an 89 R32, and i had a problem with the water line (engine side) not lining up at all... the rb20 water line came out to the side, whereas i needed it to point down to clear the exhaust housing on the rb25 turbo.

I had to make one up... however, are the connections the same for all water lines in regards to connecting them to the engine? ie, same location?

If this is true, all you need is this line instead of making one yourself... anyone know?

Ah ha I was looking for a thread like this to ask some questions aswell..

I think someone should do a sticky on RB25 turbo's onto RB20's as it is very common.

My questions are: My comp cover reads 45V2 just like the one in this picture

http://image-cache.skylinesaustralia.com/f...-1142290998.jpg

But I have the steel front wheel.. so all fingers point to my turbo being a series one? Can someone confirm that because every page I look at gives a different opinion.

Now, my second question... how much of a problem are snapped off studs in the back of the exhaust side where the turbo bolts onto the dump?

There are 2 snapped off studs still in the holes, and 2 studs that aren't snapped but still intact.

Looking at this picture here:

http://image-cache.skylinesaustralia.com/f...-1142291057.jpg

The 2 that are intact are the ones on the bottom where the dump attatchs to the turbo.. so that would be in the bottom right corner of that picture (the turbine end).

The 2 snapped one's are at the opposite end, near the internal wastegate.

I've been told it isn't a major problem.. I should try and get the bolts out using the "drill" method, which involves drilling into the snapped stud bla bla bla, or I might be able to go to a local engineering shop and shout them a slab if they remove them for me.

I'm hoping this isn't a major problem as the turbo itself is in perfect condition...

Hoep someone can answer my questions.. Cheers!

I have an 89 R32, and i had a problem with the water line (engine side) not lining up at all... the rb20 water line came out to the side, whereas i needed it to point down to clear the exhaust housing on the rb25 turbo.

I had to make one up... however, are the connections the same for all water lines in regards to connecting them to the engine? ie, same location?

... just bend the f**ker a little.. They are pretty maliable, just be a bit careful and do it slowly. I may have had to bend mine slightly to get it to fit (but I forget somewhat) - but all the dimensions match up.

Like I've done, and many people have also, there are no differences between the locations of the actual water and oil locations or threads used on RB25/RB20.. therefore no different lines are required.

They use the exact same exhaust manifold, same gaskets, same dump pipe, even the the rb20/25 turbos are exactly the same "configuration" in terms of where the water and oil lines come in and out.. etc.

  • 2 weeks later...

ok... sorry to bring up my old thread, but having since decided the time has come to get this rb25 turbo installed, i have started making some enquiries...

Have visited 2 very reputable workshops in brisbane, both quoting about $300-400 to install it.

the thing that got me worried, is that one workshop said that it would be very laggy.. and that its not a very good upgrade. this workshop also said its difficult to install as the compressor has to be rotated (?)

so is this true? or should i steer clear of that workshop?

and for those that do have an rb25 turbo on rb20... how much extra lag was there?

cheers,

Warren

pretty sure you wouldn't need to rotate the compressor housing. if you have the elbow it should just bolt up..

the manifoldsd on rb20 and rb25 are the same so the mouniting position is the same.. therefor the outlet of the compressor housing should be pointing in the same correct direction.

nothing needs to be rotated..

$300-400 is reasonable.. $100/hr workshop rate x 4 hours = $400.

Look, come to the goldcoast sometime between tomorrow and monday (bar saturday.. glug glug day) and i'll install it for you for $100... I did mine, wasn't hard. You seem in pain about it. Just go for it.

I gave it a try on my old setup and i wasn't a fan.. i can show you a video at the drag strip to illustrate my point. The whole thing convinced me to go that rb25 and manual conversion that much sooner.

you will need that elbow... I don't know why people take them off, but they seem to 'disappear' regularly.

it is a little laggy truee.. ESPECIALLY on auto rb20det.. but i am not sure what else wouldn't be either. you can't even stall it up as there is nothing until about 3500rpm (stall is about 2500rpm - so thats like 1000rpm of like nothing).. Thats not heaps.. but seeing as with an auto that takes while to spin up.

just wait for the big head of steam at 6000rpm upwards ..compared to hte lack luster drop off of a standard turbo

ur always going to be a little bit behind with the auto ..... but u wouldnt of stayed auto this long like i have if u didnt mind that to start with.

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