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Hi all, I have an RB25det with Garrett 3076 running 14psi. Currently on standard manifolds and unopened motor. Basically wondering what would be next step for more power, have been told cam gears and 21psi wastegate spring then a suitable tune, what's everyone's opinions? Also I'm currently not sure what supporting mods the car has (I bought it the way it is mechanically) in terms of injectors, afm, coilpacks, fuel pump etc. so some advice on what supporting fuel and spark upgrades are needed would be great and/or what it more than likely has.

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The potential here is huge but it sounds like you don't know very much about the set up. Is it externally gated?

I'd be talking to a tuner. find out what injectors you have and pull out the fuel pump to see what you've got there too. ECU? What colour are your coilpacks? we can likely tell you which ones they are

If you could go E85 you can make serious power on a 3076 + stock RB25det.

but seriously take it to a tuna if you don't know much about it

The potential here is huge but it sounds like you don't know very much about the set up. Is it externally gated?

I'd be talking to a tuner. find out what injectors you have and pull out the fuel pump to see what you've got there too. ECU? What colour are your coilpacks? we can likely tell you which ones they are

If you could go E85 you can make serious power on a 3076 + stock RB25det.

but seriously take it to a tuna if you don't know much about it

Internally gated, black coilpacks, apexi fc.

the coilpacks are probably nissan. 14 psi is low boost for that turbo there is a lot more power in it on pump 98. I don't know where you got 21psi from but you could run an EBC and with a tuner could turn up boost provided your fuel system keeps up. Could you post a picture of the injectors? sounds like they are probably standard which will max out around 250rwkw-ish on that turbo, don't quote me on that (maybe someone else can butt in here).

If you don't mind travelling to North Ryde, Toshi does a great job of tuning at a decent price and he is very safe.

he's on the forum here or you can look him up on FB

It's got an eboost 2, I think the pint was more that if I want more boost I need to change the waste gate spring. I'll see if I can get a pic tomorrow morning n post it up. Haven't heard of toshi before, does he have a shop, or?

bring to tuner, up boost, tidy up tune, fry tyres..

Tuner will then tell you if:

- you need new injectors

- you need new fuel pump

cam gears, cams probably not needed.. many guys on SAU fry tyres with 300kW+ on 98 with stock cams & stock cam gears.

bring to tuner, up boost, tidy up tune, fry tyres..

Tuner will then tell you if:

- you need new injectors

- you need new fuel pump

cam gears, cams probably not needed.. many guys on SAU fry tyres with 300kW+ on 98 with stock cams & stock cam gears.

Cool sounds good. What ballpark figure is tune going for these days?

Cool sounds good. What ballpark figure is tune going for these days?

depends where you go, most tuners like to charge for a full tune (even though they don't do it)

Will I need to change fuel lines and fuel rail for E85 or just injectors and pump?

I would say so, but I have a few friends that run jungle juice in their EVOs and are using stock fuel lines. Injectors & pump if you need to, if there's enough supply save your money for beer.

E85 460L/h Walbro pumps by Ti Automotive can be had for $200 ish delivered, Tuff performance had a pretty cheap sale not long ago.

Definitely going to need to do more research in regards to what's required, not sure if I'll need a surge tank (and of course the extra pump to go with it), should also ditch the special for an ECU that can take flex sensor, seems things are starting to add up pretty quick. Got a budget of around $1000, not thinking that will be close lol.

Are you tracking the car? If not, you don't need a surge tank. And a single intank Walbro 460 will do the job.

But I don't think your budget is big enough to convert to E85, especially if you don't have big enough injectors. You'd be better off doing the wastegate spring and upping the boost. Maybe if you find out your injectors are a bit small then you can stretch the budget a little and see if you can get some ID1000's, then you'll be almost set to go to E85 when you get some more cash.

Edited by Hanaldo

Yea pretty much what I was thinking

just to make it worth it, get to the shop and quickly delete your existing tune so they have to tune it from scratch-ish (probbaly have other maps they can use from other cars and touch up)

but for what it is worth lol

just to make it worth it, get to the shop and quickly delete your existing tune so they have to tune it from scratch-ish (probbaly have other maps they can use from other cars and touch up)

but for what it is worth lol

Lol

Want to get into some drift days, so probably should

Keep the tank full, you'll be sweet :thumbsup:

I don't see the point in a surge tank unless the car is mainly used for track. If you're just doing the occasional track day then I don't believe they are necessary.

I find the skyline tanks pretty good in design, I drove my car around Wakefield into the last 1/4 and no fuelling issues at all.. mind you, it's still a stock piece of shit but you get the idea.

Hi all, I have an RB25det with Garrett 3076 running 14psi. Currently on standard manifolds and unopened motor. Basically wondering what would be next step for more power, have been told cam gears and 21psi wastegate spring then a suitable tune, what's everyone's opinions? Also I'm currently not sure what supporting mods the car has (I bought it the way it is mechanically) in terms of injectors, afm, coilpacks, fuel pump etc. so some advice on what supporting fuel and spark upgrades are needed would be great and/or what it more than likely has.

Z32 AFM or R35 GTR AFM , 550 or 740cc nismo injector if 98 octane fuel , boost controller HKS EVC or Blitz dual solenoid , bigger fuel pump.

Stock engine 17psi max for safe , 0.8m gap spark plugs.

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