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hi all

im just after a little help

i have a r33 gtst and i want to hit 300rwkw with my rb25

i havent got my power fc, z32 afm or injectors fitted yet so no tune either

current mods are fmic, full 3" dump/exhaust, nismo fuel pump, fpr with a gt3076r on the standard manifold running 1 bar

would anyone have any idea what power figure to expect with the ecu and injectors fitted and tuned?

i was told to by a certain tuner to expect 220-230rwkw..... that sort of hurt my feelings as i was hoping for alot more

he also said i need to do alot of internal work to get 300rwkw running reliably all day everyday

and to be honest i dont have a clue about internal work, ive have never looked into it and never had any internal work done.

so what im really wanting to know is what everyones opinion is on what power figure i should be hoping for with what i have when i get my tune

and also what type of internal work i should think about getting done to lead me in the right direction...

also, i had a look at the rb25 dyno page and there was alot of guys who had really high dyno readings with very minimal work

some guys had no internal work done at all and were very close to hitting the 300 mark...

so thats why im so confused :)

any info would be great, any links or anything....

help a lost member out :)

thanks

chris

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well internal work isnt mandatory.........

some engines last some dont, comes down to the engines health and the tune really

some people say mid 300s some say 400 can be done with the rb25 on stock internals

how big are you balls?

higher hp = more wear and tear = engine dies faster (in theory anyway)

if you cant afford a rebuild, id keep it mild

The tuners remarks about reliable, are pretty fair.

Chase 300rwkw, will it last forever? No.

A while? Yes.

How long is a while? Its anyone's guess :)

Whats your budget? Thats a key factor more than anything else.

Realistically i think you should lower the aim to 260-270rwkw, and a 2835 or similar would then be the perfect set-up for a stock internal RB25 and make a fast streeter. And give you the best all round performance.

For 300rwkw, you have to set up a frame in turbo, and then added lag for not a lot more peak, which you might as well go bigger again and then full rebuild and blow a house deposit :)

I had a 300rwkw+ RB25, have my day again i'd go the 260-270rwkw option as response is all i chase these days. (hence RB26/GT-SS with 1bar on ~3500rpm) :D

rough figures

bottom end

pistons 1k

rods 1k

gasket kit 400

a/m headgasket 300

bearings 300

oil pump 400 for n1 or 1.3k for jap a/m ones

water pump 200

jun crank collar 200

head

cams 900

valve springs 450

valve guides 400

prep, deck, bore, clean the block

800

pressure and crack test head

1k

assembly

800

remove and install engine from your car

1.5k

that is nearly a complete overhaul

some would say valve springs, valves etc arent needed @ your power level

and just use a drop in set of cams, then you think about sump extension if you want to do some track work etc etc

all comes down to budget

hmmmmm

i think i might steer clear of internal work,

wouldnt mind getting a metal headgasket and some cams

i dont really want to spend that kind of money on my car....

as R31Nismoid said, "260-270rwkw"

if i can get i figure like that with no internal work and the engine still being reliable ill be happy :)

Get an aftermarket ECU,555cc injectors,Z32 AFM, and a good clutch. You already have the turbo so that is the easiest and most cost effective way to get 260-270rwkw.

So cost wise without labour you are looking at:

ECU=$1200-$1700

555cc injectors=$800

Z32 w/plug=$320

Decent clutch=$600-$1000

Modifying a car for more power is not cheap, and if you try and cut corners it will cost you more in the long run. So do it properly first and you shouldnt have too many problems.

me personally i dont rebuild the engine unless i have to

ill make watever power the standard bottom end can put out and when ever it blows up thats when ill go threw rebuilding it

just put it together and see watever power it makes and enjoy it when it blows up then look into rebuilding it

im making 360kw out of my RB26 and im still running a standard pistons, rods

i dont expect it to last forever but when it does let go then ill look into rebuilding it for now ill just enjoy it

personally i think a Rb25 making 300rwkw will last a while as long as u have a good tune and u stay of ur rev limiter

Edited by STR8E180

I have 300rwkw, and havent changed anything internal.

Worked fine for ca 10.000kms, have a tikkingsound in my intake now but i dont think its anything serious.

specs at my signature. I live in norway so i cant compare prices with you...shit is expensive here, and the postage from ex japan is enormous.

Cost/benefit ratio = bang for buck .

Always best to have an engine in a healthy condition if your not going inside it .

Usual deal IMO externally , PFC , Z32 MAF , injectors , IMO cams ie Tomei , proper spec bolt on turbo .

Basically my path over time - though I'm getting a head modified and which means things like healthy valve guides and a bit off to raise the lowish CR are part of the re co that goes with a good head .

I agree with those above meaning 300's a higher state of tune than you may like to live with .

I wish people would lean more towards having bucket loads of mid range torque and nice throttle response .

I reckon Hp/Kw numbers mean little aside from bragging rights , being engine rev based numbers they means jack unless you drive everywhere at peak revs .

Make it go like buggery in the mid range because the average passengers butt dyno cops enough of a hiding to make them think its pretty enthralling .

My opinions only , cheers A .

thanks for all your respones and opinions, they have done enough to change my mind to not do any internal work

paulr33 i also agree with what your saying about just buying a 300rwkw car instead of building one,

and discopotato03 im with 100% in saying 300rwkw is like a bragging right figure, i am after reliability, response and mid range torque

as much as id love to hit that 300rwkw, i guess im not that concerned anymore :)

There are heaps of skylines out there that have hit the 270-280rwkw mark using the GT3076/GT30R or HKS 2835 or 3037 [and others in the same range], they will all do it with the right supporting mods and also make very good mid range. If 300 was your goal, I'd look at the RB30/25 build and/or meth injection.

But if you really want dependablity, reliability, efficiency, and economy, you can't go past the above turbo set ups. You won't be the fastest kid on the block, but you'll be fast. Anyway there is always someone faster, so pretty pointless really [but they may not be as reliable etc].

300kw is one thing, having a good capable car is another.

I would be looking at an all round packgage of power, suspension and looks for a great street car. I car making 230kw with the goods in the other departments may be a better all round car, the kw figure is a bit of a wank to you mates.

No offense to Tebie (because he is obviously one of the more receptive guys asking this kind of question, good on him)... but far out - I don't know how Nismoi, discopotatoe, paulr33 and the rest have any hair left, or a macro which says 'search' :banana: Well done guys.

  • 3 weeks later...

dude u sound like u hav a pretty good setup for the street. just get it tuned to 15-17psi n leave it at that. should make around 350 atw with that n b pretty responsive. just wat u need

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