Rb25Det Neo Bolt On Questions

[Matamata]

I have been running a 25det neo in my r32 for a few years running the following set up:

Walbro in tank fuel pump

Electronic boost controller
3" exhaust
Front mounted intercooler
Pod Filter
Tuned with nistune on BP 98 fuel it made
300 hp 295 ft/lb


Having done 12 or so drift days I am wanting to up the power but i want to focus on mid range power / torque specifically , wanting to make a nice torque curve, not focused on a peak kw/hp number but want excellent throttle response.
I have already upgraded the drive line as the rb20det box is finally starting to rumble since i rebuilt it 2 years ago when i did the engine swap.

I am wanting to do bolt on modifications to bump the mid range, i don't want a really narrow power band that kicks in late in the rpm.
There will be plenty of people out there that say build a rb30det but the neo block is still mint condition, makes no blow by so i would rather have a crack and just doing a few bolt on mods and seeing what i can achieve.

Plans so far are
Link g4 computer (can remove a.f.m)

Leave the intake manifold stock and run a blitz style V-mounted intercooler with the intake and outlet on the same side

After market injectors (not sure on what brand or size yet, just know i dont want hi-flowed injetors)

Fuel cell and surge tank set up, not sure on what fuel pumps to run yet, i want to run E85 though so will need to change all the rubber hoses

Turbo, not sure what to run yet, i want to go with an internal waste gate type to keep the actuator and it's rubber diaphragm away from the heat. From the dyno thread on here it looks like guys that run modified stock turbos are way down on torque despite being similar kw number to guy running the likes of garret gt30 series turbos. Could it be worth talking to a turbo guru and getting something made specifically for the task.

Exhaust manifold, not sure what to do here, stock cast manifold is known to be good for not cracking but is it going to be restrictive?
There is a local shop here that guarantees his stainless manifolds against cracking and that the will make more power than off the shelf manifolds.

Cams and adjustable cam gears, Pon cams are damn cheap, are they going to benefit my mid range goals or would something custom or standard be better?

Head gasket, would it pay to upgrade to a steel headgasket? Would it help response bumping the compression up a little by running a thinner gasket?


Thoughts and suggestions? Am I over engineering it?

I'd prefer to plan it all out first than rock up to the tuner running a generic china turbo, exhaust manifold, front facing plenum and come away with 300kw but a dyno plot looking like Mt Ngauruhoe

Thanks in advance!

[RBrennan25]

I'd say go have a look at the Hypergear thread. Plenty of good results with slightly different set ups to read through. I'd say depending on how much you wanna spend and what your actual power goals are, this would be where I'd go:

Xspurt 1000cc injectors

Walbro 460 pump

Hypergear highflow

Link G4

Will net 300rwkw and be pretty damn responsive. If you feel the need to do cams, do the valve springs and what not with it. Will probably add another $1000 to your build but no point doing one without the other.

And let the varying opinions start

[Josh080691]

I got a hypergear high flow for sale only did 5000km before a Camry decided to write my car off

[Josh080691]

Also have nismo 740cc inj and a brand new Apexi pfc with El hand controller all for sale if interested

[Dobz]

It depends on how much more midrange you want without sacrificing bottom end torque.

Upgrade turbo (gt3071) or equivalent

Put some gtr injectors in and retune.

Should beef up the midrange at minimal cost.

[hypergear]

For around 260rwkws with same sort responds as your stock turbo. The best option is to find an blown R33 turbocharger and send that in for high flow. Every thing bolts back the way it is and factory looking.

[Josh080691]

My turbo above is a r33 high flow was only done by stao about 8 months ago and 4 of those the cars been off the road haha

[Josh080691]

Also has stao braided lines etc took me 2 hrs to install

[KiwiRS4T]

What Brennan said - Injectors, Hypergear turbo, new fuel pump Link G4 (get a mac valve to control boost). No need to change manifolds - spend the money on a good tune.

Buy Josh's turbo or get Steve Murch to make you one.

[Josh080691]

Stao might have a record on when I bought it but took me a few months to install after purchase. If interested send me a pm

[iruvyouskyrine]

First of all good attitude, knowing what you want and not being someone willing to cheap out at every turn, make massive dyno numbers and have it all reliable.

You have the basis for a great thing going with all the correct supporting mods. If I was you I would get some 1000cc Bosch EV14 injectors through scottynm35 on these forums. You have a walbro already so fuel system is done. The Bosch injectors also have an added benefit of fitting into the standard neo rail with mucking around.

The only thing left to get is Z32 AFM and a turbo. I would be going a 33/34 high flow from Hypergear, or one of their SS1PU or SS2 offerings for a little bit more poke than a standard highflow will give you. It's a true performance literally bolt on package that will tick all your boxes.

[iruvyouskyrine]

Also here is my dyno graph.

Standard unopened 25 neo, Hypergear internal gate SS2, Bosch 1000cc injectors, nistune ecu, z32 AFM, Gtr intercooler, 3" exhaust, standard intake and exhaust manifolds tuned on 98 octane. It was a powerhouse everywhere in the rev range, drove amazing and was perfect for drifting.

[Matamata]

Thanks so much for the replies guys, just the sort of info I have been looking for.

Out of interest, is there any sort of advantage running the z32 afm when the link g4 allows the tuner to just run off map sensor?

Im guessing I would possibly be able to stay with nistune running the z32 afm?

[KiwiRS4T]

Missed that you have a Nistune. Don't bother with the Link then save yourself a couple of grand - just get a Z32 AFM

[RBrennan25]

Yeah somehow I missed that you have a nistune as well. Really the only reason to upgrade to a new ecu (link, haltech, etc) would be if you want to run e85. They also give you a bit more accurate knock protection and a few other input and outputs which will help accurately tune the car.

But really that part is optional. It won't be cheap but I recon if it were my track car running 300rwkw I think I'd want the protection of e85 and other things.

[Josh080691]

<-- also has genuine z32and plug