Garrett GT3040.

[Freebaggin]

WelL done STEVE!! So i'm not the only one who believes in the .82 ex. housing. To me it is almost perfect for the rb25. all u need now is some cams and dial her in and u be smiling until the top half of your head falls of.

The guy who posted this originally has the GT30-40 intended for an RB20, so the 0.87 A/R would be crap.

Joel,

I was thinking about a better wastegate actuator as well. I don't really have a major problem anymore, holds 17psi well with the BOV mod I did.

I still don't quite understand how a harder spring would make a difference, although I haven't really thought about it either. Thing is, I want 8psi for around town and if the spring is set at "14psi" then I assume it will remain shut until that boost is reached? No good.

I dont intend runnign more than 17psi (1.2bar) anyway so I might be fine with the current setup, woudl rather spend on cams and nice exhaust manifold.

[Cubes]

Freebaggin,

It also would come down to the EBC. Mine would do what ever boost I pumped in to it but I would notice some where around 500rpm boost would drop .5psi then creep back up to the dialed in boost. It strugged but would do it.

I have heard some good and bad things about the HKS EBC. Origionally I was going to buy one then at the last minute lost my deposit and bought a Blitz.

The older HKS EBC's are crappy, apparently the newer ones hold boost a bit better.

Thing is, I want 8psi for around town and if the spring is set at "14psi" then I assume it will remain shut until that boost is reached? No good.

yep thats it.. I personally don't mind high boost all the time as with the RB20 if you drive normally the most boost it will make is around 5psi. BUT It is a bit of a pain in the arse when you try to take off a little quick in first and first gear snapps 1bar hard causing wheel chirp and makes you look like your thrashing it.

[Steve]

Got cams, dont think they, well exh, is dialled in too well as yet. I think a 0.87 may be a bit big for an RB20 too, but then again, I think a 3040 may be a bit big for an RB20 - depends on what you want though - Two different people can take the same car for a spin, one love it the other hate it.

Freebaggin, just stick with 1.2bar all day every day, it would make life more interesting:) You know you want to:p

[RB GUN]

Hello Guys,

Ive just drop off my car at the mechanic and ill get it back probably on next thursday or friday... So stay Tune for the ( Fingers crossed) result.

Cheers

--- Babak ---

[Steve]

which setup did you end up going for? make sure you post up results:)

[RNS11Z]

Not sure if this info will help but i had a garret gt30 with a .7 front cover and .82 rear housing on a rb25. With 1.8bar i made 320rwkw. full boost was between 4-4500rpm. It was a very smooth power band. Power would start to drop off @ 7200rpm. It went to as low as 290rwkw @ 7600rpm with my old engine and set up.

[RB GUN]

I will defenetally post the resault... Mymechanic said : dont forget that u got stock internalls so dont exept big powrer , and i asked him how much u rekon? he said maybe 300 rwhp..

hes ganna set the boos to 16 to 18 psi and i think that would be enough for me for now till i get my internalls done or i swap the engine to RB25-26 and then i can talk about big power.. hehehe

So stay Tune...

Cheeres

--- Babak ---

[benm]

You can get way more than 300rwhp out of stock internals, infact i'd say closer to 340rwhp by reading other peoples posts and cars i've seen.

[Roy]

Im with benm, i wouldnt go changing the internals of an RB20DET at that power level. Even though it is essentially a 100% increase over a std RB20DET, you are essentially increasing the effeciency of the engine with most of the mods (IC, filter, Exhaust) with only the turbo boost pressure increasing the stress on the engine.

There is evidence that boost doesnt actually hurt a turbo engine as much as revs as long as the tune is up to scratch.

Intersting to see your results...

[B-Man]

Whoops - well I just got an HKS 3040 (1.12 AR exhaust ) & HKS high mount manifold - it may be a bit big for my RB25DET - but cause my internals are done, headwork, cams, cam gears and higher redline - I'm hoping it will be OK..... we'll see I guess...

[blk^r33]

how much who i gt3040 cost me and would i need a manifold

[blk^r33]

how much will a gt3040cost me and would i need a manifold

[Steve]

1.12, man thats farking huge. Nice turbo though, merli had (or still has) one - if you need to upgrade the turbine housing, I can put you in touch with a place in the us that supplies genuine HKS turbine housing cheaper than direct from japan.

[B-Man]

[RNS11Z]

Ive got a 1.05 rear housing. To be honest its not that laggy at all. B-man if you get the right headwork and cams done your car should be over 500rwhp

[2rismo]

So with all these GT3040's going around, who has the best price for one?

Adrian

[RBsileighty]

I will defenetally post the resault... Mymechanic said : dont forget that u got stock internalls so dont exept big powrer , and i asked him how much u rekon? he said maybe 300 rwhp..

hes ganna set the boos to 16 to 18 psi and i think that would be enough for me for now till i get my internalls done or i swap the engine to RB25-26 and then i can talk about big power.. hehehe

So stay Tune...

Cheeres

--- Babak ---

What injectors did you end up running with this setup? I can't wait to hear about your results!

[Freebaggin]

B-Man, that's gonna be fantastic mate, like you say, you've got the support gear to go with it and you'll be able to rev the tits off it to make use of the power band shift to the higher RPM.

Interesting the difference between the Garrett and HKS GT3040 CHRAs:

Garrett

Comp, trim = 56, 60mm/82mm

Turbine, trim = 84, 60mm, 55mm

HKS

Comp, trim = 50, 58mm/82mm

Turbine, trim = 84, 60mm, 55mm

Minor differences in sizes. With that 1.12 housing it will be huge power!

[RB GUN]

RBSileighty - ATM i got the standard 272cc injectors, my mech. said that hes ganna power run it first to see if i need the injectors if so ill upgrade them to 600cc ones.

I cant wait myself either to see the resault.. im ganna go and have a look at the car tomorrow to see how far he went. his 1 of the best mechanics around.

Cheers guys

--- Babak ---

[RB GUN]

one more thing i was ganna say was, i dont think if im ganna do my internals, why? coz dont forget that it still is a RB20, so may be next step for me would be RB25 or 26 + forgies + my turbo setup = low 11s.

How does that sound? its true that the turbo might be a bit small but by then ill think about it... may be a big ass T51R SPL $$$ or TRUST TD06 or 7.. GOD knows better

Any ways.. Stay tune.

--- Babak ---