Help reliable 5-600hp

[Cummins-907]

Picked up a 98 skyline GTX-T with the RB25DET paired with a 5 speed manual. Looked up the Vin says 25GT-X Turbo (series 1). 

 

-First question is what is the best way to find out what series RB25 it is whether series 1, 2 or NEO it's missing the plastic cover on top of the engine and I've been told it is a NEO

 

I'm looking to make 5-600 hp to start but the more the better its going to be a street / drift car with the occasional drag events for fun

 

What should I be looking for to achieve this goal, a build list would be great and helpful.

 

So far I'm looking at 

-plazmaman short runner intake 6 or 12 injector 

-artec exhaust manifold with probably a Garrett 3660 reverse mount

(Would like to do antilag on a button with a bigger turbo)

-haltech 2500 ecu with the screen the replaces the triple gauge pod in the center

 

I am in the US and have a 10-15k USD budget any help, insight or suggestions is appreciated 

[PranK]

This might help identify the RB25 you have; 

 

 

[GTSBoy]

If it's an R34 it's definitely a Neo.

If it's an R33 (were there any '98 33s?) then it's definitely an S2.

There is no chance that it is an S1.

Don't do anti-lag. These things are getting to be as rare as hen's teeth. The days of being able to grenade a motor and just pick up another from the wrecker for $1000 are so far gone here in Australia that every wanker that ever did it is regretting doing it now.

[Cummins-907]

2 minutes ago, GTSBoy said:

If it's an R34 it's definitely a Neo.

If it's an R33 (were there any '98 33s?) then it's definitely an S2.

There is no chance that it is an S1.

Don't do anti-lag. These things are getting to be as rare as hen's teeth. The days of being able to grenade a motor and just pick up another from the wrecker for $1000 are so far gone here in Australia that every wanker that ever did it is regretting doing it now.

It's a 98 R34 sedan with 51,XXX km on the clock extremely clean no valve train noise and not a single issue with it. I'm just looking for some more power and dress up the engine bay a bit so it looks more presentable. Antilag was an idea for quick spool but I don't want to ruin it so I won't go that route

[GTSBoy]

Well the obvious solution for that sort of power level is a G30-660 or similar (assuming you're talking engine HP and not some bullshit wheel HP, otherwise you'd probably be looking at a -770).

Then you just need fuel pump, injectors, management, consideration of oil system upgrade and engine breathing control, clutch, diff, and brake upgrades, big intercooler, money put aside for breakages to all of the driveline components, and so on.

You don't need the plenum change - it will hurt street performance. (Yes, it will make more power, and yes it looks "better", for a given definition of "better", but that's no reason to change things IMO). It will cost you torque at the bottom end.

This is a standard weekend build here in Oz, for one of these.

The secret sauce is in fitting enough engine protection sensors and setting the ECU up to use them so that you don't trash the engine the second something goes wrong. Oil pressure, oil temperature, coolant pressure, EGT, are all good things for that.

[Kinkstaah]

Also, when it comes to HP and Reliability, it REALLY depends on your use case. And you have to be honest. You also need to remember there's basically 0% chance of a reliable, 600HP RB25 that is doing 1 track day a month for multiple years.

If you're cruising around on a twisty road and spend a cumulative 15 seconds of full throttle use a month, your definition of reliable will change drastically.

[PranK]

1 hour ago, GTSBoy said:

were there any '98 33s?

Yep! Not many though.

[Cummins-907]

On 7/24/2024 at 7:45 PM, Kinkstaah said:

Also, when it comes to HP and Reliability, it REALLY depends on your use case. And you have to be honest. You also need to remember there's basically 0% chance of a reliable, 600HP RB25 that is doing 1 track day a month for multiple years.

If you're cruising around on a twisty road and spend a cumulative 15 seconds of full throttle use a month, your definition of reliable will change drastically.

 It does run on a lot of back roads and slide some of the corners and highway use. It  sees track days maybe 4 times out of a year I would like to build it up a little bit and have fun with it.

The only issue I have with it is the bov stays cracked when cruising around 70mph and I try to stay out of that

[GTSBoy]

46 minutes ago, Cummins-907 said:

The only issue I have with it is the bov stays cracked when cruising around 70mph and I try to stay out of that

When you say this.....is it the stock BOV or an aftermarket venting BOV?

If it is the former, then there is no problem, This is normal and desirable. It is not a BOV. It is a "compressor bypass valve" which is designed to do 2 things. The 1st is to act as a BOV, when required. The 2nd is to open when under lightload (ie, vacuum in the manifold) and allow air to flow around the compressor, thus mechanically unloading it, thus requiring less drive power (from the turbine), thus using less fuel, and theoretically (at least) allowing it to spool up faster by allowing the engine to ingest air via the bypass (and hence generate increased exhaust gas) before the turbo gets a chance to pump it.

If it the latter, then venting BOVs on stock ECU are arse AIDS and should not be used.

[robbo_rb180]

if wanting reliability and that level of performance a dry sump is mandatory for circuit stuff as you'll just be filling the head with oil.

easy and reliable setup with potential for more later
Hypergear bolt on turbo or a g30-660 with T3 rear housing .92
external gate mod to factory exhaust manifold with 45mm waste gate
plazmaman/pwr intercooler
oil cooler
1200cc injectors
460 TI/walbro with upgrade relay and wiring/pwm control
turbosmart fuel reg
Link g4x plug in ecu with knock, oil, fuel pressure sensors, 3 port mac valve, DBW conversion
Quality clutch kit- NPC is what I've used for a long time

READ THE WHOLE OIL CONTROL THREAD

Could do major service while there and maybe headgasket, studs and valve springs.

as soon as you whack a massive turbo and short runner intake on a street car they are useless and not practical the above will be a fun and reliable 400-430hp on E85 all day with correct maintenance and mechanical sympathy.