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Hey guys, i own a r33 gts25 non turbo, and was wondering if a ecu remap would increase power through out the whole rev range, plus remove the limiter? Although i currently have no mods, i heard that a ecu remap could give me some power. If this ecu remap is worth it, is there any places in melbourne that will actually do it, if so how much??

Also i use 98 ron fuel and was wondering if tuning the car to run just 98 ron fuel will increase power aswell?

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if you were to do a full exhaust, pod filter, cams and tune you'd maybe get a 25hp gain if you're lucky. natro's are hard to get power out of and take big money to do it. if you want a powerful/fast NA then you bought the wrong car.

as for removing the rev limiter, what would you want to do that for? you won't gain any power as peak power is made below redline by about 1000rpm. all you would do is drastically shorten the life of the engine.

Welcome to the forums mate. I think its definitely worth looking at the costs of your modifications and whether its worth it to you. Things like an exhaust and decent panel filter/pod filter are going to make it sound a bit better, but not much else. Having said that, 140rwkw that the skyline in the video produced is very impressive in my opinion for a na. The gtst i bought was dynoed when it was dead stock @ 145rwkw, so its right up there with a stocker gtst. Again, i think it would come down to the price of these modifications in the first place, because gtst models can be had for next to nothing these days and have much more tuning potential. Thats of course unless you are on your p's and cant have one. Anyway, give it some thought, and enjoy your skyline ownership!

Thanks buddy, and yea im on my p's, if it were upto me i would definitely get a turbo skyline, i was even consdiering driving a turbo illegally but then kjust thought of modding my non turbo, but the amount id have to spend just doesnt seem worth it, i mean for 2000 all i can get is those things listed above but if the skyline were turbo, i could get 400-500 hp with 2000, like new turbokits, plenums etc

Yeah man, the way i see it, on your p's you dont have too much choice. Everyone gives the na skylines such a hard time on here, but 140rwkw is definitely no slouch. thumbsup.gif

I had a vt ss 5l on my p's which was legal at the time, and with a manual gearbox, extractors, intake etc it was PLENTY for a p plater! I never dynoed it but i know it was around 140rwkw, so in my opinion, that sort of power is quite decent for a na 6 cylinder. I say 2k to get that level of power from a 6 isnt too bad man, good luck!

Thanks buddy, and yea im on my p's, if it were upto me i would definitely get a turbo skyline, i was even consdiering driving a turbo illegally but then kjust thought of modding my non turbo, but the amount id have to spend just doesnt seem worth it, i mean for 2000 all i can get is those things listed above but if the skyline were turbo, i could get 400-500 hp with 2000, like new turbokits, plenums etc

you won't get 400 to 500hp from a turbo skyline for 2k unless you use evertyhing second hand or a cheap chinese lag monster turbo and cheap nasty manifolds, etc. a ball bearing turbo will set you back about $2000 (plus a few hundred for oil and water lines and fittings), ecu from $1000, not to mention injectors, afm, exhaust manifold, and you would most likely be up for a rebuild shortly afterwards as the stock internals don't last that long above 300kw. bare minimum to get that power would be $4000.

n/a skyline with exhaust, cams and nistune ecu, produced 140rwkw, very close to the turbo models ;p

maybe some one like mad082 can answer how much it would cost to reach the power figure this skyline was putting down.

Because in comparison to the Na RB25DE skylines ive seen this is an impressive result.

at a guess, about $2000 for tune, cams and cam gears. what is in doubt though is the accuracy of the dyno reading. the reason being that an experienced dyno operator knows how to alter certain parameters to trick the dyno and see bigger gains (even if they only get a 10% gain from it it is still over 10kw). also in question is the safeness of the tune as well as what fuel was used. i've seen certain tuning workshops tune cars, then put a tank of c16 in, bump the timing up to suit, do the power run that which they use to show the owner how much power it made and then put it back to 98 octane fuel settings. the owner has no idea until he puts it on a dyno again and the power isn't as much as what it made when tuned. a guy i know had something like this happen to him. his car made something like 450hp when it was tuned and i don't think it has made over 415hp on any other dyno since. you have to remember that the tuning company is the one who put the video on youtube, so there is every chance that they have tweated a few things to make the outcome look better than it actually is when they sent the car out the door. it also looks like the car isn't tied down which would see a very slight gain in power as it takes away some of the rolling resistance.

the other thing is that if the car had had a blown headgasket and had the head machined then that would give a slightly higher reading than a car with the stock gasket in there as it would have higher compression.

at a guess, about $2000 for tune, cams and cam gears. what is in doubt though is the accuracy of the dyno reading. the reason being that an experienced dyno operator knows how to alter certain parameters to trick the dyno and see bigger gains (even if they only get a 10% gain from it it is still over 10kw). also in question is the safeness of the tune as well as what fuel was used. i've seen certain tuning workshops tune cars, then put a tank of c16 in, bump the timing up to suit, do the power run that which they use to show the owner how much power it made and then put it back to 98 octane fuel settings. the owner has no idea until he puts it on a dyno again and the power isn't as much as what it made when tuned. a guy i know had something like this happen to him. his car made something like 450hp when it was tuned and i don't think it has made over 415hp on any other dyno since. you have to remember that the tuning company is the one who put the video on youtube, so there is every chance that they have tweated a few things to make the outcome look better than it actually is when they sent the car out the door. it also looks like the car isn't tied down which would see a very slight gain in power as it takes away some of the rolling resistance.

the other thing is that if the car had had a blown headgasket and had the head machined then that would give a slightly higher reading than a car with the stock gasket in there as it would have higher compression.

wow, since i joined SAU ive come to learn, that the performance of cars isnt as simple as reading a power figure. There are so many factors etc. that contribute to a cars actual real life performance.

prob sound like a bit off a noob, but ive learnt alot

wow, since i joined SAU ive come to learn, that the performance of cars isnt as simple as reading a power figure. There are so many factors etc. that contribute to a cars actual real life performance.

prob sound like a bit off a noob, but ive learnt alot

x2 mate. I didnt realize before i joined this forum that power figures can be effectively fudged. I was of the opinion 'a dyno is a dyno' if that makes sense. Sadly enough it seems some companies use these fudged figures to quote their products too. I guess it comes down to real world driving experiences.

there is fudged data and there is inaccurate data. just make sure to not get the 2 confused. inaccurate data in the case of dyno readings just comes from dynos that are a bit out. you will never get 2 dyno readings that are exactly the same, but they should be close. if you get one that is noticably different (either higher or lower) then you can usually put it down to the dyno error rather than operator error (if you are simply getting a power run done and they aren't charging you for tuning where they want to show off their skills).

and yeah, the max power a car puts out is somewhat meaningless. average power is what makes a car fast. no point having a big turbo that makes 400hp at 8500rpm if at 5000rpm it's only making 150hp because even a stock v6 commodore will be a pair of tail lights off in the distance by the time you get it to come on boost.

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