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dunno if its just me but the sensation of 300rwkw in a GTR is peanuts compared to what u feel in a 300rwkw GTS-T

the weight definately comes in to play

then there is the power delivery of the turbo(s)

and i'm pretty sure the AWD has an effect too... dunno if its just me but I seem to feel the rush more in RWD cars compared to AWD ones

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Makes 280rwkw@13psi and 315rwkw@19psi

Obviously boost is tapering off up top with the 19psi tune - otherwise you'd be making at least 330rwkw judging from your 13psi tune.

I agree that the rush feeling usually comes from the mid-range torque and yours should be decent, say~590nm. Considering torque to weight though and that would only be a touch more than my GTST on 1 bar. So I can relate to that fast, but not THAT fast feeling.

My personal rule is you need a 20% increase in torque for it to feel substantially different - but that is HIGHLY subjective.

10% improvements you clearly feel but it's not a big leap.

5% improvement you only feel if you are attuned to it.

A 20% midrange difference is almost exactly that between your 13psi and 19psi.

A 10% midrange difference you can test by comparing between 16psi and 19psi.

If you had that 10 or 20% increase again would it be sufficient? If you think so then a E85 tune might be for you, complete with slightly bigger turbos and much bigger injectors/fuel pump. Otherwise you'll need to pump 22 or 25psi into that thing with some bigger turbos.

Then again, perhaps only a slightly higher torque but over the wider range might just do the trick. Hence the garrett consideration. Did I just talk in circles?

my 5cents (soon to be 10c)

hmm... my car still makes me smile when I open it up... 360rwkw and no traction issues whatsover (unless you clutch dump at 8000+rpm)

you really benefit from the extra traction a GTR has when changing hard from 1st to 2nd... the old GTSt used to spin the rears for a moment which would blunt acceleration a little... however the GTR almost breaks your neck

RWD is more fun as it hunts for traction and squirms around under power, but the G's created by wide tyres and AWD make for more of a push in the seat

when bored of the power just go E85... I'm going to for shits and giggles;)

its the torque that you feel
I wish people would stop saying things like this, torque and power are directly related, at a given rpm with a given power level, you will always have the same amount of torque and vice versa.

You feel the acceleration, this is caused by power OR torque, they are both the same thing when you are talking about acceleration.

You do realise that you took exception to "it's torque that you feel" and then said they're both the same thing?? :wacko: wat.

They're not the same thing. Torque is an instantaneous force. It is what you feel. Acceleration is the byproduct of a force. Torque is closely linked with power as you say but you don't go "wow I really felt the kinetic energy of my car increase over the last second" you say "wow my butt is being pushed into the seat". That force is produced by torque. Torque provides a force on the driving wheels which produces acceleration (it becomes a linear force at the tyre/road boundary). The engine is doing work to achieve this and the net result over 1 second is your power figure.

It definitely comes down to torque delivery. If you get a hard hit of boost (and torque) in the midrange then it feels like a big rush. If your turbo is very progressive and linear then you don't get the same smack in the back it's more of a smooth push.

I should have Clarified that the power figures were high(19psi 315rwkw) and low(280rwkw) boost settings not progressive increase in the one run.

From 2000RPM start in 3rd it hits full boost(19psi) at 4200RPM.

really starting to think about some new Garretts now....... Wife says "Thanks alot"...NOT!

Thats the weight :D

My car's acceleration, coupled with 4.3 diff is absolutely savage for only 280rwkw if im lucky enough to hold traction (its borderline)

i agree, light with high diff ratio is the way to go if you want that feeling of psycho acceleration.

really starting to think about some new Garretts now....... Wife says "Thanks alot"...NOT!

Hahaha I bet

From reading about what you think of the N1s, -7s will just give you more response but not much more top end. You wont get much more of a 'thrill'. I think you should go the -5s. It sounds like your all about the rush and perception of a fast car. -9s are a great overall solution but it sounds like you dont track your car and want the max straight line thrill.

It must be hard to get a car to give you the thrill of a big bike.

Info from PaulR33's signature:

Garrett 2860R-7's 0.42a/r (60.0mm) compressor 0.64a/r rear (HKS GT-SS equiv) = 300 to 330rwkw range

Garrett 2860R-9's 0.42a/r (59.4mm) compressor 0.64a/r rear (HKS GT-SS equiv) = 300 to 330rwkw range

Garrett 2860R-5's 0.60a/r compressor 0.64a/r rear (HKS 2530 Equiv) = 360 to 420rwkw range

Garrett 2871R-10's 0.60a/r compressor 0.64a/r rear (HKS GT-RS Equiv) = 440rwkw to 500rwkw

Edited by Harey
Build the motor tough, add GTRS's, e85, 25psi and grippy tires.

You'll feel the rush then

If the wife doesnt like the sound of upgrading to Garrett turbos, I am not sure if she will like the sound of that! hahaha

definetely need to experience that

can i be in the passenger seat sometime?? :)

DONT DO IT!!! Then you will have the same problem as Turbo Dave because then anything less than that wont feel fast anymore!

Edited by Harey
Thats the weight :)

My car's acceleration, coupled with 4.3 diff is absolutely savage for only 280rwkw if im lucky enough to hold traction (its borderline)

thats an alternative, put a shorter diff in it.

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