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Ok, i have my own thoughts, but they are arent based on experience and stubborn pride :Oops:

In an R32 GTST running Works Whiteline susp and a 1.5LSD and 245/45/17 D01Js what is a power figure where the car turns from a fun spirited, challenging car to drive around a circuit to a lesson in futility.

Have to make a decision in the next day or two should i chase more power or just more midrange. The midrange once is tough pill to swallow as spending thousands of dollars to make boost 1200rpm sooner but still only make around 260rwkws is hard to justify.

So obviously 400rwks is too much, and power delivery makes a big difference, basically i need to be convinced that going RB30, which requires new gearbox clutch (more $$$) is going to result in a driveable car, no just a tyre frier.

My thinking around 320rwkws courtesy of a displacement and turbo size increase is when you start to have a look at yourself and consider that you have so much power that you are forever lighting tyres in a straight line. Is that figure even too high?

Obviously a 100% increase in power over 1500rpm is going to hurt traction, hence the tendency to look at bigger displacement to smooth out the power delviery.

Help ?

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320 rwkw is a truck load of power.

It's probably what a V8 supercar has at the wheels.

And a V8 supercar is a fully prepped race machine and they struggle with traction.

Probably 250kw would be a really nice amount of power to have at the wheel with a nice fat power curve. That way you wouldn't be caught in the wrong gear too often.

Troy i remember you talking about this last sunday at the dyno day.

250rwkw seems to be a good for everyday driving in a RWD turbo car that has a nice power curve and brings power on at around 4000rpm, well from what i have experienced with my car anyway. Anymore and it starts to be become scary and a pain in the ass coz if you try to change lanes in a hurry or accelerate hard you just end up going sideways or smoking the tyres and getting no where fast, from what i have experienced also.

Should be an interesting thread

Troy, buy a GTR, you know you want to join us :D

LOL dont want to join you, want to beat you!!!! :)..its a baby brother thing :Oops:

I would consider it if my car didnt already owe me the money it does...anyway for a road car i think GTRs are better, for the track ill take a GTST

250rwkw seems to be a good for everyday driving in a RWD turbo car...

Thats the thing im not worried about the street, i drive liek an old lady, im more interested in what it will be like on the track

Hi Roy,

This seems like a similar debate i have been having with myself.

I want to have the power, but i want to be able to use it effectively instead of just being a stupid tyre frying machine.

I think the people with RB25's making 300rwkw will experience a different power curve than that of the RB30. Hence why it would be a more 'scary' option. My reason is that they would have to rev the car more and boost would coming on hard and sharper.. (a more convex power curve as opposed to a more concave power cuver ??)

i think what will make a car more 'futile/frustrating' to drive is when it lags lags lags then jumps 150rwkw in the space of 500-1000rpm . Would be a big handle with the sudden rush of power. I enjoyed that with my RB20 for a while. I still feel the RB30 will give a more gradual increase in power, sure it will light up the tyres if you mash the pedal to the floor, but it wouldnt be as sharp or as harsh as the RB25 doing it.

i have no idea if that made sense... i just woke up :)

I think 300rwkw is more than enough power in a RWD car, especially if it's a street/circuit car. If you could make that power with an almost linear (re:N/A) power delivery I think it would be more enjoyable, controllable and faster than some of the larger nothing-then-wheelspin setups that some GTS-t owners have.

Then again, you know how to steer pretty well, and can learn how to regulate a 350rwkw car with some moderation on your right foot. But it's more fun just to plant it and try to fight it! :)

My experiences have been with lower power figures you can drive it up to the limit easier, but there is a critical point where the power is an all consuming thing, and it bludgeons everthing else into insignificance.

My experiences with 220rwkw have been positive. It is scary in the wet with my fat power curve, power and boost starts at around 2000rpm. Denham was on the money. Just putting around, you then give it a spurt and it can go anywhere (remember my tyre choice is not to use sticky's).

Open areas where I can give it plenty, like on a racetrack, it is much nicer. It stays on the boil and traction is less of an issue as you are generally going well above the speed where inertia fights traction and acceleration. It doesn't feel like a weapon, but the speeds build very fast. It is however a pig off the line and I won't be winning any drag races.

Make some time one weekend and we'll get out for a longer drive to highlight the issues.

Forget about peak power readings. Why would having similar peak power readings, but with a much quicker, easily controllable, more fun package be disappointing? You can't say "ooh er, look at my peak power reading", but if your goal is to impress people, show someone that knows what they're on about and they'd look at the WHOLE graph and go all ga-ga. If you want it for yourself to have more fun in/go quicker around a track, I'd take a fat torque curve over a high peak power figure any day.

I could put together a 200rwkW car that is painful to drive, and a 250rwkW car that is both quicker in a straight line and around corners. I could also build a 200rwkW car that is quicker than a 250rwkW car. It's all about useable power and how accessible the power is. Fat midrange and not having boost come in like a light switch will give you that.

There seems to be a lot of feedback that says 300rwkw on an RB25DET is enough.. but on an RB30, can you push out a bit more power and increase the driveability due to the larger capacity?

What is the driveability of an RB30DET (with all appropriate systems) be compared to an RB25DET at same power levels.. e.g. is similar power levels on an rb30det RWD going to be fairly similar, worse, or better than an RB25DET at similar power levels??

Forget about peak power readings. Why would having similar peak power readings, but with a much quicker, easily controllable, more fun package be disappointing? You can't say "ooh er, look at my peak power reading", but if your goal is to impress people, show someone that knows what they're on about and they'd look at the WHOLE graph and go all ga-ga. If you want it for yourself to have more fun in/go quicker around a track, I'd take a fat torque curve over a high peak power figure any day.

 

I could put together a 200rwkW car that is painful to drive, and a 250rwkW car that is both quicker in a straight line and around corners. I could also build a 200rwkW car that is quicker than a 250rwkW car. It's all about useable power and how accessible the power is. Fat midrange and not having boost come in like a light switch will give you that.

Have you actually built these cars? or is it just theory?

They actually tested this out on a bunch of gts-t's in serious performance 5 dvd, where 2rismo's current car was one of the cars tested with a bunch of other various mod gts-t's

Forget about peak power readings. Why would having similar peak power readings, but with a much quicker, easily controllable, more fun package be disappointing? You can't say "ooh er, look at my peak power reading", but if your goal is to impress people, show someone that knows what they're on about and they'd look at the WHOLE graph and go all ga-ga. If you want it for yourself to have more fun in/go quicker around a track, I'd take a fat torque curve over a high peak power figure any day.

Sorry, i should perhaps clarify. If im making 250rwkws currently, and simply simply remove all my 'bolt on betty' bits and throw it at an RB25/26/30, well airflow is airflow and the engine wont make bigger numbers. And you are right that the torque will be improved, but how often do you come out of a turn on th track at 2,000rpm where you need that hit of power.

Sadly i cant post a dyno of my current setup, but at 4,500rpm in 2nd gear it was making 1 bar (the few times i had the boost up that high), that was with a far from optimum tune. So in the rev range that i use on the track the thing would have percolated along well.

So you would take a fatter torque curve any day, would you spend 6k on a 20rwks average power improvement? Like i said i dont need to win any class of racing etc, just be quick and fun to drive so have to justify the expense...BUT if i can throw 320rwkws at the chassis via a swap from TD06-20G to 25G ec then it seems more worthwhile

But it's more fun just to plant it and try to fight it! :D

:) ...its not about whose fastest as there will always be faster cars and drivers, its about who has the most fun, somehting you have witnessed when a passenger in my car, i sure do enjoy it, but if it were a little more challenging to drive like your R33 then id be that little bit happier :D

troy from experience with my car atm, 250rwkws is a nice figure for everyday driving

uve still got enough power to boot without worrying too much about traction problems (well i dont seem to with 18's)

and ive got a nice bigish turbo running pissant boost (10psi)

so a smaller turbo with better spool and response would suit better if u were just aiming for this figure

my 2c

Troy - you said you've never even really driven a GTR before so how do you know what they are like to drive? I wouldn't say that driving around Sandown in my GTR was EASY by any stretch of the imagination.

If I can get the boys to get the gearbox back in maybe we should go for a drive this weekend to give you some food for thought!?

Anyone else wanna tell Troy to get a GTR? LOL

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