Jump to content
SAU Community

Recommended Posts

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.

  • Replies 174
  • Created
  • Last Reply

Top Posters In This Topic

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.

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

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.

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 ---

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...

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...

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!

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!

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 ---

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 :D

Any ways.. Stay tune.

--- Babak ---

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • The rain is the best time to push to the edge of the grip limit. Water lubrication reduces the consumption of rubber without reducing the fun. I take pleasure in driving around the outside of numpties in Audis, WRXs, BRZs, etc, because they get all worried in the wet. They warm up faster than the engine oil does.
    • When they're dead cold, and in the wet, they're not very fun. RE003 are alright, they do harden very quickly and turn into literally $50 Pace tyres.
    • Yeah, I thought that Reedy's video was quite good because he compared old and new (as in, well used and quite new) AD09s, with what is generally considered to be the fast Yokohama in this category (ie, sporty road/track tyres) and a tyre that people might be able to use to extend the comparo out into the space of more expensive European tyres, being the Cup 2. No-one would ever agree that the Cup 2 is a poor tyre - many would suggest that it is close to the very top of the category. And, for them all to come out so close to each other, and for the cheaper tyre in the test to do so well against the others, in some cases being even faster, shows that (good, non-linglong) tyres are reaching a plateau in terms of how good they can get, and they're all sitting on that same plateau. Anyway, on the AD08R, AD09, RS4 that I've had on the car in recent years, I've never had a problem in the cold and wet. SA gets down to 0-10°C in winter. Not so often, but it was only 4°C when I got in the car this morning. Once the tyres are warm (ie, after about 2km), you can start to lay into them. I've never aquaplaned or suffered serious off-corner understeer or anything like that in the wet, that I would not have expected to happen with a more normal tyre. I had some RE003s, and they were shit in the dry, shit in the wet, shit everywhere. I would rate the RS4 and AD0x as being more trustworthy in the wet, once the rubber is warm. Bridgestone should be ashamed of the RE003.
    • This is why I gave the disclaimer about how I drive in the wet which I feel is pretty important. I have heard people think RS4's are horrible in the rain, but I have this feeling they must be driving (or attempting to drive) anywhere close to the grip limit. I legitimately drive at the speed limit/below speed the limit 100% of the time in the rain. More than happy to just commute along at 50kmh behind a train of cars in 5th gear etc. I do agree with you with regards to the temp and the 'quality' of the tyre Dose. Most UHP tyres aren't even up to temperature on the road anyway, even when going mad initial D canyon carving. It would be interesting to see a not-up-to-temp UHP tyre compared against a mere... normal...HP tyre at these temperatures. I don't think you're (or me in this case) is actually picking up grip with an RS4/AD09 on the road relative to something like a RE003 because the RS4/AD09 is not up to temp and the RE003 is closer to it's optimal operating window.
    • Either the bearing has been installed backwards OR the gearbox input shaft bearing is loosey goosey.   When in doubt, just put in a Samsonas in.
×
×
  • Create New...