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Hey guys, i have a practically stock R34 2 door 25GT, was wondering if anyone has pushed out a good 200rwkw out of their N/A's for these cars, cause so far i only seen the highest being 162 odd RwKw in the threads.

That being said how much would it cost to push out 200+ Kw out of an RB25DE?...

I know there are different methods and techniques to get power out of these engines, alot of my mates and mechanics alike have said this path isn't worth going down, but i thought trying here would benfit and possibly give me new hope to redoing this engine.

And if anyone is going to tell me just buy a 34 GTT or save up for the RB25DET, its not really an option for me because i wanted to do this as something unique and something that will get attention for being non turbo yet equally powerful to a turbo model. It's something different to me and something i wish to do if possible.

If anyone has N/A engines pumping out over 200+ or even above 180+KW @ wheels on similar models can you please tell me what you did and how much it costs!????? it would be greatly appreciated!

Thanks in advance.

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throw pin away, and wait for grenade to explode...

That will certainly get the attention he's after.

something that will get attention for being non turbo yet equally powerful to a turbo model. It's something different to me and something i wish to do if possible.

If the displacement is equal, you will never get a NA car to match a FI car once you start modifying both. You can stay "non turbo" and run nitrous, but in my books chemical induction does not count as "normally aspirated". Running nitrous is as much "cheating", when it comes to making more power, as boosting an engine.

You could sink a bucketload of cash into a 3.0L engine with the most lightweight internals and a stratospheric redline, but the thing will run like a dog down low and so you'll probably still get beaten by a cheaper turbo car making practically the same power with more midrange, or a turbo car that's spent as much as you have, or blown away by a turbo car that's had the same amount of money thrown at it.

Get a Hiclone, Good for 11ty hp and 100 k to the litre.

Seriously the nitrous idea will work but is just as illegal as a turbo is for a p plater. When it comes to n/a the old saying about cubic inches is very relevant. Its easy to forget how little displacement a skyline engine carrys when you see some of the hp figures on the turbo'd engines but at the end of the day you are playing with 2.5 litres of naturally aspirated engine. It really isnt enough to make any worth while gains unless you mod the feck out of it and live with the aforementioned lousy down low running.

just going to add my 2 cents here.

Hey guys, i have a practically stock R34 2 door 25GT, was wondering if anyone has pushed out a good 200rwkw out of their N/A's for these cars, cause so far i only seen the highest being 162 odd RwKw in the threads.

i think you have answered your own question there... if the guys haven't posted in the power thread then they pretty much won't tell you if they did.

That being said how much would it cost to push out 200+ Kw out of an RB25DE?...

are you kidding? pull any number out of a hat! i've got a pretty good idea how to make that kind of power with an NA RB and i've also got a pretty good idea of how much it will cost. lets just say you'll be looking at over $15K in parts alone. and no i will not tell how to make that much power.

I know there are different methods and techniques to get power out of these engines, alot of my mates and mechanics alike have said this path isn't worth going down, but i thought trying here would benfit and possibly give me new hope to redoing this engine.

your mates are right. however i say do it and post it here - i dare you! :thumbsup:

And if anyone is going to tell me just buy a 34 GTT or save up for the RB25DET, its not really an option for me because i wanted to do this as something unique and something that will get attention for being non turbo yet equally powerful to a turbo model. It's something different to me and something i wish to do if possible.

take the leap and do the R&D for everyone.

If anyone has N/A engines pumping out over 200+ or even above 180+KW @ wheels on similar models can you please tell me what you did and how much it costs!?????

i don't think anyone is going to spoon feed you and give you a recipe on how to make that much power. that kind of power on an NA RB will involve alot of R&D and is certainly something they will hold close to themselves. however if you had SEARCHED the forums you might have found a couple of hints.

If the displacement is equal, you will never get a NA car to match a FI car once you start modifying both.

does F1 count? :)

Get a Hiclone, Good for 11ty hp and 100 k to the litre.

Seriously the nitrous idea will work but is just as illegal as a turbo is for a p plater. When it comes to n/a the old saying about cubic inches is very relevant. Its easy to forget how little displacement a skyline engine carrys when you see some of the hp figures on the turbo'd engines but at the end of the day you are playing with 2.5 litres of naturally aspirated engine. It really isnt enough to make any worth while gains unless you mod the feck out of it and live with the aforementioned lousy down low running.

bingo noelski

young ones these days they aim high huh?

i'm even tempted to lock this because it's just well... useless

177kw is as much as I've seen from any nissan DE and that was a big build 30DE... in an R31, it is due for another update tho, so we'll have to keep an eye on it.

I also know an RB30e thats hit 155kw

but they've had stupid, stupid amounts of work done to them, and like the others have said 'sif these guys are going to reveal the depths of their secrets to a random.

if you want big N/A power find a VH41 and plonk it in.

skits r31 is atm being redone to run around 12:1 compression and that will have to be solely on methanol/pump combo (even at present thats running on a touch of methanol)

thats wihout ITB - so if you were to fabricate a custom set of boxed ITB's, run 12:1 compression and run on methanol/98ron mix, and have a 8500 rpm redline to make any power at all, then to be beaten by a turbo making the same power cause your power doesnt start till 5500rpm then fine, be my guest

it would sound like a f**king screamin jet when it revs high, but imho that amount of work is not worth it for a street car

maybe a dedicated track car, but it would be a pig on the street

skits r31 is atm being redone to run around 12:1 compression and that will have to be solely on methanol/pump combo (even at present thats running on a touch of methanol)

thats wihout ITB - so if you were to fabricate a custom set of boxed ITB's, run 12:1 compression and run on methanol/98ron mix, and have a 8500 rpm redline to make any power at all, then to be beaten by a turbo making the same power cause your power doesnt start till 5500rpm then fine, be my guest

it would sound like a f**king screamin jet when it revs high, but imho that amount of work is not worth it for a street car

maybe a dedicated track car, but it would be a pig on the street

the amount of money to balance the entire bottom end + forgies for anything over 7000rpm is the only thing that has put me off...

maybe one day, i will throw one into a 240/260Z

If you want an NA engine for the pure reasons of response and having grunt instantly (within a certain rev range) then do it. Turbos are overrated in my opinion unless you're chasing 200+rwkw.

If you want outright power figures, but to be different..... then no, prob not gonna be worth it.

NA engines are just different.... if you are a true NA fan and want good power... 170-180rwkw is doable, and personally I don't think it will be such a pig as everyone says.... provided you go and do it properly with an RB30DE running VCT etc..... $$$

Probably best to use a NEO head so you have the best VCT system available, if you have cash to blow then adapt the GTR 6-throttle setup to a NEO head and you basically have an M3 style motor in your hands. But....... budget $20K for the build.... you migt get some change from that to pay for it's first service!

If you're happy with NA 150-160 rwkw (with lots of torque still...) then go for a 25 head, stock internals...... just get the harmonics issue of the 30 bottom end sorted and you'll see some nice revs.

Power becomes less important with 30DE's..... it's the extra torque that makes them quick.

If you want big numbers...... and one of the quicker cars out there - fail. Drop a turbo motor in..... 25DET cheap these days.... or even just turbo a 25DE, put 10psi through that with supporting mods..... higher comp + boost = responsive power, just don't go silly on the boost or it will pop.

thanks guys, much appreciated, it was a long shot but hmm, i just wanted ideas, trust me i have looked around, we even thought going the whole boar and stroke, blueprinting the engine and supercharging it but...thats something im Reasearching right now Eug :laugh:

Money is not an issue here, might be young, but arn't the younger people in these threads going to be carrying on the skyline traditions? (call me a die hard fan) :S Either way when im off my p's i already have enough money to buy my R34 GTR....why stop there when i can save up for a 35 these days :D it's not the money its the change, and if it can't be done then i would stop here on my search, but i know it can be done.

Well the money thing isn't entirely true, Eug, if i were to take any money out of my GTR 34 savings i would most certainley mod the hell out of my current 34 and show you what you want to see lol, but thats a long shot, you'd be the first to find out if i did it!

Anyhow thanks for all the help....ill keep looking into alternatives and direct inputs.

if you guys don't mind me hijacking the thread a tiny bit here...

i see a lot of VIC guys on their P's have non-turbo Skylines...

is that because you're not allowed a turbo vehicle?

i would say that is pretty much on the money. it's so weird seeing NA skylines worth the same (in some cases more) than the turbo ones.

that is ridiculous, my friend moved from WA to VIC and told me i'm lucky that i'm allowed a GT-T and i just gave him the weirdest look...

feel sorry for you guys over there in VIC, come to Perth, you'll be amazed at how many 17/18 year old guys have R34 GTR's here... *shakes head*

we take it for granted over here

i see a lot of VIC guys on their P's have non-turbo Skylines...

is that because you're not allowed a turbo vehicle?

I think most state in AU has that law now, except here @ WA (& maybe NT or TAS... not sure, don't hear much from neither state).

THANK GOD for that :laugh: .

far to much work involved to be worth it. ITB's, Nitros, CAMS, Exhaust, timing gears, lightened pully's, gearbox (if an auto), injectors, etc.... the list goes on.

Is that not the same for turbo?

welcome to the modified car world..

skits r31 is atm being redone to run around 12:1 compression and that will have to be solely on methanol/pump combo (even at present thats running on a touch of methanol)

thats wihout ITB - so if you were to fabricate a custom set of boxed ITB's, run 12:1 compression and run on methanol/98ron mix, and have a 8500 rpm redline to make any power at all, then to be beaten by a turbo making the same power cause your power doesnt start till 5500rpm then fine, be my guest

it would sound like a f**king screamin jet when it revs high, but imho that amount of work is not worth it for a street car

maybe a dedicated track car, but it would be a pig on the street

Yeah its running about 25% mix of methanol at the moment, I'm fitting it with a microtech LT12 though, and tuning in an extra injector for full time water/methanol injection, so i can just fill up at the pump still.

also i only intend to rev it to about 7000rpm, revs generally replaces displacement for more power, that said though i don't want it to be too much of a pig down low, I'm certain ill get more than the power i want without needing to rev it further than that. Also, best cure for cam lag (or any lag) is compression and ign timing, my car still has way more down low than a standard rb30, and buckets more than a 25de (with stock vct setup, should get improvement on adjustment). But it isn't much in comparison to what its got up top, and it revs so fast in the first 2 gears compared to my turbo. Also i just love the feeling of stomping the throttle and having the rear wheels spinning before your foot hits the floor, N/A response :). Also, i cant see there being too much of a power difference between one large tb and 6 smalls on the same type plenum, and I've got enough response, thats why i didn't take that route

I think most state in AU has that law now, except here @ WA (& maybe NT or TAS... not sure, don't hear much from neither state).

THANK GOD for that :) .

yeah Tas has no laws like that, but we're pretty strict on hooning, since everybody drives around at half the limit and as if the accelerator maxes at 10%, so if you stand out to be moving quicker than the pack on take off, and your in a modified car, your as good as gone :).

I'd trade no turbo for that any day

power = capacity, revs, timing, tune, flow, weight, efficiency (so cold intake, cool combustion chamber, intake and exhaust scavenging, strong spark - example, index the plugs, get colder type, slightly over gap and run strong ignition)

CR tip - you want the most possible practical compression on the most efficient squash (you don't want to see cylinder walls at tdc) 12:1 is doable on good pump fuel with no extras (like my water injection) i just didn't do it the best way possible the first time around.

flow is obvious, bigger isn't always better, match length and diameter for most efficient velocity at peak power/air flow in and out (if you go from 2 pipes to one, they should have the same total area with a smoother transition to keep air speed with no pressure drop), match the cam. Polish it all, remove ridges, etc

Remember, you cant just wind up the atmosphere, you only have the atmo 14.5psi to play with, you don't want to be lower than that pressure by the time it hits the cylinder

Big power should really be a walk in the park, i mean look at dons original engine, 151rwkw, untuned, technically stock with a mild cam and extra throttle body (30 bottom, 25de pistons, all stock bits inc head, on budget exhaust, stock plenum, breathing hot air, only revving to 6k etc).

150kw is pretty decent to start on, if you cant get another 30+ kw from working it from there, there really is a problem somewhere. People just need to get back to the old, every kw counts, if you gain 2-3kw from all plugs indexed, 1 or so from polishing the inner plenum, its worthwhile doing it, unlike typical turbo modifications where its just - get a bigger turbo, run more boost, instead of fixing problems, like intake pressure drops and limited flow.

also, people cant forget - its also illegal to modify your n/a engine under the p plater laws....

Edited by SKiT_R31
hmmm........... 100 hp shot of nitrous............yummy................................. :P

Thought you were selling your bottle of juice? what happened to it?

and yeh the laws here in Vic are super....tight i should say....they come down hard now...1000 bucks, then 5000, then they sell your car....so its not worth the risk or i too would be one of those 18-20 year olds with a 34 GT-R :) that being said i posted this to see what i can do without cops noticing when they open the hood, they havn't seemed to evolve too much other than harsher penalties and more regular pull overs.

That being said i'd much rather a 25DET than a 25DE, but i thought if possible to pull good power from it than it would be something moreso unique than that of the DET's you see plenty of now days in any state.

thanks for all the inputs guys. :D been helpful.

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