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Just wondering how hard it would be to get 130rwkw out of an N/A keeping 100% stock compression. Budgeting around $3500-$4000 for this, not enough?

2.5" Catback with extractors. $400-800

Pod filter with airbox and CAI. $100-200

Adjustable camgears, Upgraded cams(tomei?). $1500-1600

GReddy Emanage Blue. $500-700 + tune

Would this net me 130rwkw? Things like injectors/Splitfire coilpacks would be pretty useless on an NA motor unless its going to be turbocharged dowm the track right.

Have already gone through the NA performance thread.

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Not saying it can't be done... but what is your reasoning behind keeping it N/A? P-plates, or just 'because you can'? I assume that if you're willing to spend that kinda $$$ on an N/A engine, it's probably in pretty good nick and with low k's.

I've got an N/A 33, and looked down this path... I decided that for the cash I'd have to part with I was better off building an RB25DE+T. I've bought everything required now (turbo, intake and exhaust manifolds, injectors, dump/front pipe, eManage Blue, FMIC + piping, boost gauge and boost controller, etc) for just under $1.5k, I'll be doing all the labour myself (minus the tune) and I'm hoping for well in excess of what I could reach N/A for twice the price. It'll be a high-compression turbo setup, so boost levels are limited (i.e. I'll run 8-9PSI tops I'd think...) but with the extra punch down low from the higher comp, it should be a nice fun drive. I guess we'll see soon! I'm hoping to do the conversion early January when I've got some annual leave booked, so I'll be posting up about it when it's all done.

Just my 2c and maybe worth a consider? Of course if you've got other reasons for sticking with N/A, then ignore this :)

Edited by Samon

Samon already said what I have to say lol Unless you're going to go all the way with it and increase compression etc... you're going to hit the ceiling pretty quickly on an RB25DE and your wallets going to be a whole lot lighter in comparison to doing a DE+t, particularly when you compare the gains to be had.

Now first up, cost is going to change considerably depending on whether you install yourself or take it to a workshop.

You should be able to pick up a eManage Blue for less than that, I got mine private sale but new for $320...still need to add your optional harnesses if you need them. For a DE+t obviously you need the optional ignition and fuel (allow $140 there), and then the ignition signal adaptor is around $30 I think from perfectrun, you'll need that if you're using the R34 Neo Engine. Depending on where you live, some tuners do the Greddy Blue installed for a pretty good price. If you're going to have it installed for you allow a few hundred bucks or so there.

Allow up to $400 for a good tuner, depends how many hours of tuning you need though.

If you're looking for a nice big power figure, particularly with bigger cams and all, maybe look at a 2.75" or even 3" catback, or opt for lower top end but better bottom/mid range. Price will vary depending on materials used, mandrel bends etc.. $400-600 for a custom mandrel bend I imagine is what you'd expect? Depends on where you go. You can quite often pick up a second hand 3" Mandrel Bend Jap exhaust for around $250 odd or less if you keep an eye out though.

Extractors you've got a few options:

Custom made with tuned lengths and HPC Coating, very pricey! Someone clarify the costs but up to a grand I think shoudl be expected.

Coby Extractors from Parts Co NZ or DKNE Extractors: Allow around $450-480 for extractors plus shipping (unless prices have changed), + $280ish for HPC Coating inside out, then fitting. Add extra if you're going bolt on and need the cat connector on them. Of course you could use heat wrap and corrode your extractors...not really worth it..do it once do it right.

Of course after that you'd want a high flow cat, plenty of hi flowing ones for under $200.

So allow very easily up to $1500 for exhaust with extractors.

You could probably save a bit on your CAI by making one yourself, plus you'll find that the off-the-shelf boxes are to suit DET setups.

Spark plugs I"m not sure if they'll need to be regapped, if so might as well throw in some new ones.

I'm not sure about fuel requirements with this sort of set up...if the stock pump and injectors can't keep up, then you'll be looking at say a Walbro GSS342 pump and some GTSt or GTT injectors depending on whether you have the NEO engine. Neo heads use top feed, but different to GTR injectors. Allow up to $300 there.

If you're going to turbocharge down the track....I would just do that to begin with.

Extractors are a big chunk of that budget alone, and unless you can recover the dollars spent later on, they're useless once you drop in a turbo.

Also have a look through the power results thread, see what mods people have done to get different power results.

The N/A path is an expensive one when aiming for big power.

The N/A path is an expensive one when aiming for big power.

+1 Exactly. 'bang-for-your-buck', whacking a turbo on is way out in front. Remember, it's still got that low-down punch from the high-compression NA pistons which (I'm hoping) should make it more fun to drive than a standard rb25det... i.e. more low-down 'get-up-and-go'.

i rekn what you should do is do mods to your NA now that would future proof yourself for the turbo down the track:

- free flowing exhaust + high-flow cat (3" about)

- injectors

- CAI

- Cams

- GTR intake plenum (not essential but with twin TBs would be nice to have)

- 5stud converstion (again not essential, but GTSt brakes could be handy to have)

with this all out of the way then you can start mounting up the parts needed for the DET converstion, ie turbo, piping, FMIC, etc

Edited by G0DZLR

If you do put bigger cams in then what Josh said really isn't too bad an idea, particularly if you don't want to do the turbo conversion till a year or so, but want more power now.

However if you don't do the cams, then bigger injectors are fairly pointless till there's a need for them, and a 3" catback is going to lower the performance down low and in the mid-range due to the volumetric efficiency.

With that said though, the cost of the cam upgrade being spent on the turbo conversion itself will be more worth it IMO, or better still use the money spent on cams upgrading the brakes.

I wouldn't overlook brakes on a high performance / turbocharged car. I just recently upgraded my brakes to GTSt (front & rear), complete with braided lines and some good fluid. I plan to swap the standard used rotors on the front with slotteds and good pads soon though, well worth it in my opinion...Nissan weren't too generous with N/A skyline brakes.

If you're looking to do a 5 stud conversion, I have a front pair R33 GTSt hubs/uprights if you're interested.

Of course that means changing wheels on an R33 GTS, though looking at the clearance on my R34 with 18s, I don't know that the stock 16s will clear GTSt calipers?

i reckon you can hit 130rwkw or at least close to it with your mods.

my old 32 hit 119rwkw with just filter, cai, 2.5" catback & walbro fuel pump.

im sure with poncams, adj cam gears (put some more timing into it), emanage + good tune for 98ron you can pull it off

Of course that means changing wheels on an R33 GTS, though looking at the clearance on my R34 with 18s, I don't know that the stock 16s will clear GTSt calipers?

assuming your talking about stock GTSt 16s with stock GTSt brakes...one would only assume that they would have been designed to fit...:nyaanyaa:

I stand corrected..I didn't realise R33 GTSt had 16s.. I assumed they were 17" like the R34 GT to GTT comparison. Still the issue of new wheels remains anyways if one is to do the 5 stud conversion.

Just wondering how hard it would be to get 130rwkw out of an N/A keeping 100% stock compression. Budgeting around $3500-$4000 for this, not enough?

2.5" Catback with extractors. $400-800

Pod filter with airbox and CAI. $100-200

Adjustable camgears, Upgraded cams(tomei?). $1500-1600

GReddy Emanage Blue. $500-700 + tune

Would this net me 130rwkw? Things like injectors/Splitfire coilpacks would be pretty useless on an NA motor unless its going to be turbocharged dowm the track right.

Have already gone through the NA performance thread.

1.) Righto, without upping the compression you're pretty much not going to get anywhere (sorry to rain on your parade).

2.) It's not the size of the exhaust that will get you a noticeable power increase, it will come from the design of the extractors, tuned length are good, mine cost me a grand at COST price.

3.) Adjustable cam gears are a great idea, cheap and can be used either turbo or N/a.

4.) Cams, not a good idea, cause they are designed differently to do different jobs, so they can clash going from N/a to turbo or vice versa (cam gears will help but not solve your problem) this is what I face at the moment (stock GT-R cams with N/a, not enough lift).

5.) Pod and CAI will only help to stop a decrease in power once the engine bay temps start to go up.

If your going to TURBO it and still want to spend that 3-4 grand my recommendations would be:

Aftermaket ECU, cam gears, exhaust and coil packs - that should net you a 10 to 15 rwkw gain at the treads N/a and all of it is useable to go turbo

- GTR intake plenum (not essential but with twin TBs would be nice to have)

GTR plenums have 6 TBs :laugh:

(AND A TOTALLY UNRELATED QUESTION - on r31skyline forum there's a button "show new replies to your last posts" that will come up with the threads you have posted in and people have replied to... is there such a button on SAU!?! or do i simply have to remember every thread i asked a question in..)

  • 2 weeks later...
Just wondering how hard it would be to get 130rwkw out of an N/A keeping 100% stock compression. Budgeting around $3500-$4000 for this, not enough?

2.5" Catback with extractors. $400-800

Pod filter with airbox and CAI. $100-200

Adjustable camgears, Upgraded cams(tomei?). $1500-1600

GReddy Emanage Blue. $500-700 + tune

Would this net me 130rwkw? Things like injectors/Splitfire coilpacks would be pretty useless on an NA motor unless its going to be turbocharged dowm the track right.

Have already gone through the NA performance thread.

Buy a SZ

i got 128 kW out of my RB25DE

with just:

Apexi Power Fc $1550

Tune in for Power FC $500

Splitfire Coilpacks $600

3" Stainless Steel Exhaust $900

Custom Extractors $680

R34 GTT Fuel Injectors $120

Trust Airnix Pod Filter Cold Air Intake System $140

hmm i think that was it :)

Edited by MissR34

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