Turbo Question

[suburban drifter]

sorry to ask stupid qestions but do i need to get bigger fuelpump and injectors before i get a new hf turbo or isnt it too important ??

i want to be running round 17 psi ?? thanks yall

[Bluprint]

It would be a very good idea, yes

computer would help too

Edited April 2, 2008 by Bluprint

[stewari]

if you want to run that much boost, at least put a fuel pressure reg in. and i wouldnt bother about injectors yet, thats just me.

[CeJay]

I'd get splitfire coilpacks too.

[BNR32t]

I'd get splitfire coilpacks too.

i am running 17psi and have no issues with coils... but my 550 injectors are at 87% Fuel is a must.

[race_snooze]

You will need!!!!

ECU of some description

Fuel pump and Reg so as to max out injectors by raising fuel pressure (not the best way to do things)

FMIC

Exhaust (other wise you are wasting your time)

Bleed valve (boost control of some kind)

Now I would go a z32 AFM as well

also some injectors

[sl33py]

LOL *BANG* the sound of a budget blowing out to 8x it's original size lol

[Bluprint]

Just like what happens every other time someone tries to do up a car...

[Bullet32]

17psi on a stock tune could make mince meat of a piston in no time... If you dont have the correct AFR (air fuel ratio) you run a high risk of detonation due to lean fuel and air mixtures.

But you might be lucky, I have heard of people doing it and not having troubles...

However, my advice is to run a maximum of 12 - 14psi with a stock R33 RB25DET computer, if you start running anything over this kind of boost you may have serious issues with your AFR's being far to lean and if you get even a small boost spike without safe mixtures you could easily end up with a piston head with a large chunk missing.

Do it once, do it right...

1st step - Fuel pump (Bosch 040 or Walbro are the most popular)

2nd step - Splitfires (or higher amperage coils) the standard coils dont have high enough amps and with more boost you could end up blowing out the spark at high RPM.

3rd step - Computer and injectors (try not to go over 550cc on a stock motor as they can be a bitch to tune if they're to big) and something like a Power FC plug in or a Microtech would be needed to control the whole kit.

Oh and make sure that you have some sort of reliable boost control and a front mount + big exhaust or you'll just choke a bigger turbo and it wont breathe enough for decent power gains.

Ive been through all of this and unless you know what your doing and can do most of it yourself it can become very expensive.

Happy shopping

[BNR32t]

My comment was regarding an rb26... And is their for usless.

[TiTAN]

Run 17 psi with your factory computer all you like and revel in the joy that is rich and retard.

[sl33py]

Bullet - I've got 740cc's goin in, stock block + GTRS, mods as in sig. Was told it'll be fine by my mechanic. Is it just 'fiddly' to do or something?

[Bullet32]

Bullet - I've got 740cc's goin in, stock block + GTRS, mods as in sig. Was told it'll be fine by my mechanic. Is it just 'fiddly' to do or something?

It really depends on your overall set up and the power that you are looking to get out of it as to which injector size is well suited.

Bigger is not necessarily better when it comes to injectors, I originally put 650cc squirters in mine and because I was building a set up more for response and track work rather than outright power or drag racing they were far to big.

When the tune was being done with the 650's my tuner had to pull out over 50% of the fuel going in to keep the AFR's right and that made it run like crap because the injector duty was to low, it also refused to idle.

So 550cc's went in and they were as big as I needed for my set up.

If youre looking for about 300kw at the wheels, which isnt a huge ask with the turbo you have then you will probably need bigger than 550's in yours, you will probably need a rising rate fuel reg to keep as much pressure in the rail as possible to.

I dont claim to be a tuning expert, but I have done just about every bolt on mod that you can do to an RB motor aswell as a lot of time on the dyno having it tuned, Im only speaking from my own experience.

[race_snooze]

I was lucky with my build, fuel pump and reg with a HKS 25/30 running 18psi stock injectors and AFM A/F were 13 to 1 (not to bad for a Remapped ECU meant for stock turbo)

[stewari]

17psi on a stock tune could make mince meat of a piston in no time... If you dont have the correct AFR (air fuel ratio) you run a high risk of detonation due to lean fuel and air mixtures.

But you might be lucky, I have heard of people doing it and not having troubles...

However, my advice is to run a maximum of 12 - 14psi with a stock R33 RB25DET computer, if you start running anything over this kind of boost you may have serious issues with your AFR's being far to lean and if you get even a small boost spike without safe mixtures you could easily end up with a piston head with a large chunk missing.

Do it once, do it right...

1st step - Fuel pump (Bosch 040 or Walbro are the most popular)

2nd step - Splitfires (or higher amperage coils) the standard coils dont have high enough amps and with more boost you could end up blowing out the spark at high RPM.

3rd step - Computer and injectors (try not to go over 550cc on a stock motor as they can be a bitch to tune if they're to big) and something like a Power FC plug in or a Microtech would be needed to control the whole kit.

Oh and make sure that you have some sort of reliable boost control and a front mount + big exhaust or you'll just choke a bigger turbo and it wont breathe enough for decent power gains.

Ive been through all of this and unless you know what your doing and can do most of it yourself it can become very expensive.

Happy shopping

+ 1 on everything said here, apart from id go 740 injectors because your buying them, you may as well go that big. mean while this is doing everything right, you could get away with doing less then half the stuff, but its all risk management!

take it easy, stuart

[sl33py]

Hmm I've got a Nismo pump instead of the rising rate fuel reg. I'm looking for 260-270, I don't like fireworks (stock bottom end!). So from what you said, I guess yeah I'm better off with my 740cc's. Will find out earyl next week anyway when John's done!

[Bullet32]

John at Trojan knows what he's doing so I would trust what he says and does, the last tune I had John do on my car is excellent.

[tridentt150v]

555 nismo injectors, 70% duty cycle, std internals except tomei sticks, 290+rwkw

I have a SARD fpr, so may help a bit?

I reckon 550's would be fine myself, but its your $$$$ and 555's cost nearly as much as 740's