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my supporting mods are

444cc injectors

huge jap fmic

gtr fuel pump

catchcan

ecu remapped to suit

19psi is for occasional squirt 15 is for daily driving. at 15psi it makes around 200rwkw.

RB20 internals are good for around 250rwkw with a propper tune.

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Wow this thread has really made me eager to hurry up and do the big change on my car...

Ive got a 25 turbo that ive gotta send to aaron, Z32, gtr injectors waiting to go on, already got a cooler full exhaust, turbo tech boost controller and the usual other mods.

Ill be reading this carefully before i do it to hopefully have everything ready before i start, stick it all together and get it tuned.... 200+ here i come!

Howd you guys find that fuel economy is now out of curiosity? same or worse?

fuel economy=Controlled by right foot,

for normal driving it's the same to the nearest 1km (still 400kms per tank)

leadfoot driving = tank gone in 250 or there abouts k's

estimated power @ 19psi?

and yeah your right about the taking a while to get to 9 psi... once its got the air flow and load happening it just shoots up from there... crazy stuff.

Im hanging out for some injectors so i can crank 230 rwkw ish.

estimated power @ 19psi?

and yeah your right about the taking a while to get to 9 psi... once its got the air flow and load happening it just shoots up from there... crazy stuff.

Im hanging out for some injectors so i can crank 230 rwkw ish.

around 230~240. I will confirm this as soon as time and dyno permits :happy:

hey dude, how does the stock internals on the rb20det hold up to 19psi?

I wound boost back to 18psi on the day, but the last few times i ventured out i had been usign 20-21psi...and the thing was fine. Did a number of laps at Sandown and other events at the Dutton Rally on 20-21psi. At that boost level it equates to somewhere around the 250-260rwkws, at 17-18psi it makes about 235rwkws.

Id say that whilst my engine still doesnt breath a drop and is running strong, i really think 16psi is the smart bet...its not suicide at 19psi, but its more base diving then knitting

How do you rb25 guys find spool up with the rb25 max oversize hi-flow?

I've got the max oversize with the vg30 rear and it's only on 11 psi at the moment

until next Saturday's tune. Anyway by the time it hits 3500 rpm it's go time.. :)

I wound boost back to 18psi on the day, but the last few times i ventured out i had been usign 20-21psi...and the thing was fine. Did a number of laps at Sandown and other events at the Dutton Rally on 20-21psi. At that boost level it equates to somewhere around the 250-260rwkws, at 17-18psi it makes about 235rwkws.

Id say that whilst my engine still doesnt breath a drop and is running strong, i really think 16psi is the smart bet...its not suicide at 19psi, but its more base diving then knitting

Sorry for the hijack, but what supporting mods do you need for 8800rpm on an rb20?

Sorry for the hijack, but what supporting mods do you need for 8800rpm on an rb20?

An engine hoist, a garage and a spare RB20. :huh:

I have another motor for the car, so whislt i dont want to blow the engine i have always thought they are a lot stronger then ppl give them credit for...so what is a used Rb20 worth? $200? So im waging $200 if i dont do anything too silly it will live a while longer.

Looking at dyno print outs there isnt any point reving the thing harder then 7,200rpm. I use the 8,800 rev limit in only 1st and 2nd gears so that it falls back into the meaty part of the curve as my engine makes peak torque at 4,800rpm. My shift point drops accordingly in 3rd and 4th gear...so saying 8,8000rpm is a little misleading. Also whe i was running 21psi, it was falling back to about 19psi up high in the rev range. Over xmas have to iron out a few bugs.

But for a reliable RB20 at 240rwkws id say keep boost to 16-17psi and a 7,400rev limit

  • 2 weeks later...
Talk about boaring the housings within a mm of its life.

Nice work. Cant wait to see how the turbo performs.

Good luck mate.

Here's a pic of the RB25 max oversize as a comparison as far as boring the housings.

The comp side looks about the same, but take a look at the exh. side :glare:

comp-side.jpg

exh-side.jpg

Here's CEF11Es again as a comparison

100_1173.jpg

ceffies-hi-flow.jpg

Edited by Lazy-Bastard
Here's a pic of the RB25 max oversize as a comparison as far as boring the housings.

The comp side looks about the same, but take a look at the exh. side :glare:

comp-side.jpg

exh-side.jpg

Here's CEF11Es again as a comparison

100_1173.jpg

ceffies-hi-flow.jpg

which rb25 highflows are these? ive got the max oversize highflow from aaron and my exhaust wheel doesnt look nowhere near the size of the first pic?:S

How hard was it getting the water lines off to modify?

On the weekend I blew a rubber hose on the turbo line which was an absolute pain to get to, if you have to pull out the metal line that goes into the block, I definatly won't be going one of these (I was looking forward to one until i realised what a pain it is)

We had a very hard time just getting a hose on/off the pipe...I can only assume getting the line out to modify is even worse?

I have been pulling off my turbo off for the last 4 hours. I would not recommend it for someone having no mechanical experience. I found there were so many little unexpected things that have slowed me down.

Its pretty obvious what has to be modified once the oil lines are off as you can see where they are restricted. I'm going down to Pirtek tomorrow to pick up my stainless braided hose and 6mm banjos and washers and should hopefully be fitting the turbo tomorrow.

Has anyone on here saved their coolant? As everything is off except for the water lines and I don't want to drain my relatively new coolant. How do I put the new turbo in without completely draining the system? Also is it worth replacing the washers on the water lines?

Cheers,

Brett

you're going to have to drain it, just jack the front up onto stands, and drain it from the rad into a nice clean bucket or something similar, let it drain then unbolt the lines etc off the turbo, when you've got the new one bolted up just pour the coolant back in

  • 2 weeks later...

Just to bump this up again, the mechanic seems to think my turbo is on its way out, so this would be the logical track to follow to fix that problem.

How have you guys with the rb20s found the turbo now its been on the car for a few more weeks, and you should have had your new tunes done?

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