Best Turbo For 'my' R33 Gtst

[series2r33]

Im at the stage now where im lookin to upgrade my turbo,

I've got: Front mount intercooler

Custom intake plenum with custom piping

80mm throttle body

Walbro 500hp fuel pump

Apexi power FC and hand controller

Custom cold air intake

E-Boost

3" exhaust with high flo cat from turbo back

...and nismo 555cc injectors to be put in when tuning with the turbo

I cant decide between the GT3540 (700hp), GT3040 (600hp), or even maybe a GT30 (500hp). I'll be leaving the stock exhaust manifold as i've heard changing it will really only give me maybe a 3kw gain, not worth it for the money spend to fit it, and to change the exhaust to fit top mount.

I want the best outta my car but i dont wanna be waiting all day for boost to kick in. I also know that the bigger the turbo, the bigger the number you'll put out on a dyno, but on the street a snappier car will be quicker despite a lower power, and thats what im after. Im askin which turbo will give me the best power and spool up in a reasonable time, ie best turbo for my car???

[fEkuaR]

youve answerd your own question mate. You want the best street turbo and considering your running stock internals the gt30 is the best option out of those turbo's. You wont be running 700hp on a stock engine.

[govich]

Get a highflow or sensible turbo if you're building a street car.

The stock exhaust manifold is horrible from an efficiency perspective.. replacing it with a proper tubular manifold will decrease spool time and promote easier flow through the head..ie. potentially lower boost for the same power.

Edited April 29, 2007 by govich

[series2r33]

I know i wont have 700hp! i never said i would, but that turbo would give me more power than say the GT30 or GT3540. And what would the differences be in spool up time? thats why i threw in the GT3040... half way... maybe best of both worlds?

Will the aftermarket exhaust manifold will effect spool up time more so than KW? is that what your saying? for an extra grand for a decent exhaust manifold and an added 3 kw, i just cant see how its worth it... unless as u say there is a "massive" improvement in spool up time

[govich]

It's up to you really. You can have a nice turbo like a HKS 2535 or GTRS and have full boost not long after 3000rpm, peak at 250rwkW and have a ball tearer of a street car that'll do low 12s at the strip. Or you can buy a GT3040 and drive around on the street with nothing below 4200rpm and wheelspin above (in the early gears which are what we use to accelerate on the street).

Horses for courses..

[series2r33]

GTRS? how many hp is that turbo?... isnt that the one thay use to get snappy response on the sr20's. Thats a 2ltr 4cyl engine, thats why i was thinkin GT3040 or GT30 not so much the 3540, simply because of the extra 2 cylinders and half a litre. The GT3040 is what they have on the XR6 turbos from factory so i know its a good turbo and i have 9.5" tyres on the back so that orta help with traction

[paulr33]

you are a clown. read the info before posting. there are a few versions of the gt-rs.

there is an sr20 version and an rb25 version. govich is spot on the money

hks gt-rs, hiflow or 2530 for mild gtst. 3040 is just more stress, lag, wheelspin, bog the dog, heat and rebuild light with expensive internals

[paulr33]

The GT3040 is what they have on the XR6 turbos from factory so i know its a good turbo and i have 9.5" tyres on the back so that orta help with traction

they actually have a hybrid gt3540. and being an inline 6, 4 litre you would expect that. it also has a cropped compressor cover to limit output.

it needs a large rear housing to handle the exhaust gas it flows but the cropped cover holds it back so saying its a "good" turbo is nothing but usless for your application.

9.5" tyres are great but what about the rest of the stuff thats required for traction? shocks? diff cradle? pineapples? bushes?

and more to the point as you step in larger turbocharges you move the power band

the hks gt-rs, 2530 and hiflow are narrow powerbands which give you linear power all the way through, that is good fat midrange and not peaking.

the 30's series turbochargers and up are usually larger exhaust housings which give you

lag lag lag lag lag lag, power, wheelspin, change gears

but its your $

do what you like

the best setup for a 30 sized turbo would be proper exhaust manifold and external gate instead of internal gate on the stock maniifold

[moonus]

mate, i say go with a high flow, that way u can run the turbo at its max efficiency instead of only using say a 3040 at well less than its max potenital. Alternitvely u can go down the hks route with a 2535 or from the feedback from users online, the 2835. I think 30's are too big for ur setup, cos im in the same boat

[sinistaGTR]

i have a gt3040 on my car .63 ex and its awesome for the street and is easier to get power out of then any sort of 28xx variant. I start boosting at 3200 full boost by 3800, should be even better with cams aswell, i find its great for street.

Edited April 29, 2007 by sinistagtst

[series2r33]

Maybe u should read what i wrote paulr33!

When did i say i wanted an internally gated turbo?! And replacing diff cradle, pineapples on a car predominatly used for street is just stupid, maybe if i was using it for track use! If the 2530 is such i good idea then how come every turbo shop u talk to tells u to get either of the 3 i mentioned?

Anyway how much is a rb25 GTRS and how many kw whould i be expecting to get

Edited April 29, 2007 by series2r33

[pixel8r]

If you're after minimal turbo lag I'd suggest something SMALLER than even a GT30. I have a GT30 on my stagea (with 3" exhaust, and 12psi boost for now) and it is a touch laggy. In a lighter car (skyline) the lag would be less noticeable but I would still suggest a GCG highflow (GT28) would give similar power for the same or less money for what you need. The GT30 will give more potential as far as top end kw but ask yourself how far you want to go?

There are other things you can do to minimize lag, but these options (ie. cold air intake, Apexi SITC and others) would apply with any turbo - therefore the smaller turbo would still give less lag. A good EBC may improve spool-up times as well.

On the other hand, a slightly more laggy turbo like the GT30 will likely give you better fuel economy for city driving whilst still giving you very nice mid-range and top end performance.

However you'll also find that to get the best from a GT30, you'll probably want to run it at 15-16psi, whereas a smaller turbo like a GT28 will be more efficient and more responsive at say 10-15psi.

I'm no expert btw, just hope I can give some pointers because I have a GT30 and whilst I generally like its performance and response, others have had better results from a GCG highflow.

To give an idea, with my GT30, boost starts to build up at 2500rpm and hits full boost (currently 12psi) around 4000rpm. It comes on strong around 3000-3500rpm and will hold boost right through to the redline without any worries. People who have a GCG highflow often report that it has similar lag to the stock turbo, if only slightly more.

[series2r33]

A good EBC may improve spool-up times as well.

I have an E-Boost so maybe that will help?

Yeah im thinking the GT30 that way u still have the high mid and top end power because i dont really feel like straping a hair dryer onto the side of my car so i can jump 10 metres in front from the get go and then get smashed because the turbos maxed out

Im not worried about "minimal" lag as it is to be expected with any turbo car making decent power

Edited April 29, 2007 by series2r33

[series2r33]

Also i dont feel like driving down the street with the turbo screaming its head of when im just going to get some milk cause the small turbos well into its power band at 2500rpm

[Andi]

"When did I say I wanted an internally gated turbo?!"

Yet in the first post you wrote:

"I want to keep the stock manifold?"

Haha abit contradicting mate. Anyhow if you're car is a street then you'd want to go the hiflow route or HKS GT-RS/GT2530/2535 as alot of the members have already said: they're power band is much more suited for the streets. You're looking at anywhere from 220-250rwkw with the 2530/2535 and around 230-260rwkw with the GT-RS, the peak power may not be as high as you want but its the mid-range punch that counts. Any of these turbo should get you into the low-mid 12's 1/4 mile and wouldn't you say thats plenty for a street car?

And why change the read diff cradle bushes or pineapples on a street car? Because it helps keep stability and if you're into drag racing it'll drastically reduce axle tramp.

EDIT: seems like you already know what you want mate. Go get a GT3071R or GT3040 as it seems to be what you're after: more top end then low end response. Just remember that you're most likely going to be pushing your engine (if its standard) at its limits.

Edited April 29, 2007 by Andi

[sinistaGTR]

yep get a gt30 you will be very happy then great to drive round town off boost, then got the power right there when you wanna have fun.

[series2r33]

"When did I say I wanted an internally gated turbo?!"

Since when is the internal gate not in the turbo?

Yeah GT30 sounds like the best bet to me, drive around sainly and not be spooling up like a wank when your not even giving it any, but yet have the power there when u wanna give it some and have bugger all lag according to "pixal8tr" who says its only a touch laggy and thats in a heavier car

[Andi]

By saying "when did i say i want an internally gated turbo?!" did you not mean that you want an external gate turbo? I really don't know where you're going with that.

Anyway it doesn't matter how responsive your turbo is, you can drive around on the stock turbo and keep it from boost. Its called your right foot.

[govich]

drive around sainly and not be spooling up like a wank when your not even giving it any

The turbo won't spool unless you're 'giving it'. I manage to drive around perfectly sanely with the stock turbo which gives a full 0.85bar at 2700rpm (on a dyno). Yet when i'm trotting along at 80 in 4th at 3000rpm, 100rwkW and easy overtaking/hill climbing is a stab of the throttle away. Have a look at how much GT30 equipped cars are making at 3000rpm.

Your choice, do you want a street car or a race car?

Edited April 29, 2007 by govich

[series2r33]

EDIT: seems like you already know what you want mate. Go get a GT3071R or GT3040 as it seems to be what you're after: more top end then low end response. Just remember that you're most likely going to be pushing your engine (if its standard) at its limits.

I've seen one with a GT3540 and hes been running stock internals on that 700hp turbo for over a year and not a hint of a problem! The rb series have strong internals, they can take a bit. i dont know why u think they'll blow up.

With the GT30 or the turbos you've suggested im not really gonna max out the turbos i dont imagine, but i dont wanna be driving around on boost when im not giving it any, street use is exactly that. its not toyko drift i want a sain car that aint on boost its whole life but that can go when i want it to