Best Turbo For R34 Without Opening The Engine

[illusiVe]

Hey all..

I've tried searching and researching the subject, esp going over the RB25DET /turbo dyno graphs.

Just trying to think of the best turbo to match a NEORB25DET without having to open the engine itself for a rebuild/cams, what sort of RWKW would i be looking at. And to go along with it, the supportive mods needed, i have a manual, FMIC, POD and boost controller, full exhaust on its way (3")

(eg i dont want a massive turbo which will get the power easily, but is lag city.. id prefer to be in the 'perfect' range for the turbo chosen, but not be pushing it to its limit so that it fails quickly)

-Any crap i can get rid out of my engine bay while im at it (stuff which isnt required) soo many hoses etc..

as always, thanks in advance.

Edited April 17, 2007 by illusiVe

[ovabooster]

GCG high flow....Good for 250-260rwkw and response similar to standard huffer...And thats about the max u would want to have with standard internals...But if ur budget allows for it, go HKS GT2835 Pros kit with 0.6X a/r...Lethal street weapon! And if u decide to do internals later on down the track the turbo good for 280rwkw.

[illusiVe]

hmm ok, i was told the GCG highflow (from the stock R34 turbo) is good to 230rwkw.. but im happy to be wrong if thats the case. Money is an issue as always, but im happy to spend it to get the response i want. is the GT2835 worth it in your oppinion? ive been recommended the GT-RS? (i dont know much about turbos models/sizes as this is my 1st turbo car) but i have a general idea for mods

[ovabooster]

I was asking the same question when i 1st got my R34...Sydney kid got 275rwkw on his R34 using a GCG highflow...But that was with cams aswell..and response as gud as stock!!! That my friend would make alot of 300rwkw RB25DET piss. It all depends on the power target u are trying to achive. So how about u tell us what ur aiming for which would help in deciding what turbo is best suited for that application...BTW if ur after 300rwkw....FORGET about response and driveability

[Birnie]

If you're still researching, don't only look at results for R34.

R33 is basically the same engine and if you see good results on the R33, that turbo will bolt straight up to your engine and is worth a look into.

There are a few other considerations but the turbo will fit.

[illusiVe]

my overall goal is response, but i want to be able to max out the engine for reliable HP.

[sinistaGTR]

well a rb25 can hold upto 300odd rwkw so there youre looking at a gt3040 you need to specify what sort of power you would like, i think your after a slide or gcg hiflow really, but you need to sit down and make a goal.

[R31Nismoid]

Same reply i usually give GCG Hi-flow.

Dont go on what "someones mates mate" told you. 230rwkw is a load of crap.

They are good for 250-260, there is load and loads of info on this topic surrounding it, results etc etc

[SS8_Gohan]

if you have a FMIC, what's a safe limit of rwkw's you can run (given a turbo change) without "opening the engine"?

[cln]

-

[moonus]

  SS8_Gohan said:

if you have a FMIC, what's a safe limit of rwkw's you can run (given a turbo change) without "opening the engine"?

on a r33 gts-t i wouldnt push more than 300 rwks on a standard bottom end

[Dale FZ1]

Re: the response and lag issue.

Some people have difficulty getting their head around lag. For some it means the boost threshold engine rpm, and for others it means transient response (ie. how long it takes the turbo to build boost from a closed/low throttle situation).

The general info you've been given indicates going for a small-frame type upgrade ie. stick away from the GT30 or equivalent medium size frame turbos. For a power target in the mid 200s I'd agree. This will keep the boost threshold down closer to stock, and depending on the impeller specs, with transient response not that far removed from stock. The different airflow capacity / efficiency of the actual impellers will tend to give a much stronger on-road feel when it is running on boost though.

Going for the likes of a GT30 would see you hovering somewhere just under 300kW but basically you'd expect the useable engine rpm to have gone up the range by 1000 odd. So it would come on 1000 later, and hold it for that much longer. My view is that you would be looking closely at gearbox/diff ratio changes to capitalise on that, which is starting to equal $$$

There is plenty of good quality information in the stickies section as you know, but I'd have to say before settling on whatever you want, write a list of EXACTLY what use you intend to put the car to, and in what PROPORTIONS. In other words, prioritise. If you drag race it every single day, then transient response is less of a concern than if you use it for daily driving and the odd competitive hillclimb or motorkhana. Work out if you're happy to sacrifice 15-20kW off the max power number in the quest for sharp/immediate response. Some people will, some won't.

Any of the commonly cited high flows seem to work very well, and the likes of the GCG and Slide units are known quantities. The GT-RS will be more expensive but if I had the $$ to spend I would probably go that way. Real world budgets applied in my case, so I went high flow and have no complaint.

Hope that is of some help.

cheers

[SS8_Gohan]

GCG vs Slide?

[illusiVe]

Can ou guys help me with a supporting mods list (eg if fuel pump, injectors, afm, new ecu (i have SAFC btw) or anything else would be needed)

[MANWHORE]

I would go for the hks gtrs if you had about 2.5k to spend. Best response, everything will bolt up perfectly, because it's a full kit. everything is included, including a heavy duty actuator, bolts, washers, lines EVERYTHING.

If not, i'd go for the gcg highflow - cheap, striaght bolt on, ball bearing. It'll make 250 rwkw EASILY. responsive.

PS: if you're looking to get a highflow, and wanna borrow an rb25 housing to take to gcg so that your car isn't off the road for as long, i've got a couple here. I've been lending them around to forum guys to help people out.

[R31Nismoid]

  illusiVe said:

Can ou guys help me with a supporting mods list (eg if fuel pump, injectors, afm, new ecu (i have SAFC btw) or anything else would be needed)

There is a great deal of information already on these forums.

A quick search, and even having a read of the Dyno Results stickies would give you what you need to know

[Bass Junky]

IF you want the BEST turbo available on the market, bar none, its the Apexi RX6B series.

Blistering response, massive power potential. But you pay through the nose.

Unquestionably best of the best for response and good power.

The Apexi turbo will make 280 rwkw and better than stock response on a skyline.

[SS8_Gohan]

hmm, tell us more specifically $$ etc...

[GUN_METAL_GTR32]

rx6 for sure

[Birnie]

....but nengun has those turbo listed as discontinued ! DOH