KO4/RS6 or KO4/24

[S2tuner]

I wouldn't hold my breath and look too much at those numbers. I am just now trying to source a full kit and fit it to my car, then map it to see if it holds its promises in terms of BHP and torque, because I've never believed in american dyno numbers unfortunately, although I have used several of them (in the US) in the past.

Mihnea

[viperbl]

I wouldn't hold my breath and look too much at those numbers. I am just now trying to source a full kit and fit it to my car, then map it to see if it holds its promises in terms of BHP and torque, because I've never believed in american dyno numbers unfortunately, although I have used several of them (in the US) in the past.

They say the wheel hp is 492, and they say this is 630hp crank.

I got 376hp @ wheels, which if times by 22% you get 459hp @ crank, which sounds right for my setup.

I you use the same method for their wheel hp you get 600hp, not 630hp.

So, 630 maybe a little high??? or are my maths out??

[S2tuner]

I don't even believe in 600 on GT25s TBH.... if the GT28RS kit I'm trying to get does 600 plus then ok fine but everyone will know it and I won't be shy posting logs and everything, even if the result is utter cr@p. In which case I'll be seriously pi$$ed off anyway.

[JonnyX]

I wouldn't hold my breath and look too much at those numbers. I am just now trying to source a full kit and fit it to my car, then map it to see if it holds its promises in terms of BHP and torque, because I've never believed in american dyno numbers unfortunately, although I have used several of them (in the US) in the past.

They say the wheel hp is 492, and they say this is 630hp crank.

I got 376hp @ wheels, which if times by 22% you get 459hp @ crank, which sounds right for my setup.

I you use the same method for their wheel hp you get 600hp, not 630hp.

So, 630 maybe a little high??? or are my maths out??

Personally, I think transmission loss is an absolute figure not a percentage.
After all, you are not changing any of those components so why would you
expect to suddenly start dissipating more power through them?

[MarkB]

I wouldn't hold my breath and look too much at those numbers. I am just now trying to source a full kit and fit it to my car, then map it to see if it holds its promises in terms of BHP and torque, because I've never believed in american dyno numbers unfortunately, although I have used several of them (in the US) in the past.

They say the wheel hp is 492, and they say this is 630hp crank.

I got 376hp @ wheels, which if times by 22% you get 459hp @ crank, which sounds right for my setup.

I you use the same method for their wheel hp you get 600hp, not 630hp.

So, 630 maybe a little high??? or are my maths out??

Personally, I think transmission loss is an absolute figure not a percentage.
After all, you are not changing any of those components so why would you
expect to suddenly start dissipating more power through them?

More pressure (torque), more friction?

[ZeroK66]

Personally, I think transmission loss is an absolute figure not a percentage.
After all, you are not changing any of those components so why would you
expect to suddenly start dissipating more power through them?

If your theory was correct then running at part throttle the car would not move until you got over like 60BHP. It is deffo a percentage... maybe the % loss does decrease slightly, the main losses are incurred through rotational mass of all the components. The rotational mass would increase the harder you tried to spin everything therefore maintaining the loss at a certain percentage rather than fixed figure.

This is one for Dr-Al to answer really.

[JonnyX]

Personally, I think transmission loss is an absolute figure not a percentage.
After all, you are not changing any of those components so why would you
expect to suddenly start dissipating more power through them?

If your theory was correct then running at part throttle the car would not move until you got over like 60BHP. It is deffo a percentage... maybe the % loss does decrease slightly, the main losses are incurred through rotational mass of all the components. The rotational mass would increase the harder you tried to spin everything therefore maintaining the loss at a certain percentage rather than fixed figure.

This is one for Dr-Al to answer really.

Not really. Power is given at a specific RPM, it's not an integral. At the end
of the day it's all energy. You are increasing the specific output of the
engine hence there is more energy available per unit time hence greater
acceleration and greater top speed. As you say, what we term as
transmission loss is mostly the energy required to accelerate the rotating
components between the crank and the road. These components don't
change therefore their ability to store and dissipate energy doesn't
either. There will be an increase in transmission loss due to increased
hysteresis but it's not linear as a flat percentage would suggest. Consider
a car generating 265BHP and losing about 80 through the transmission -
if you raise this cars power to 530 do you really think it's reasonable to
lose 160bhp through the same transmission components? 80bhp is a
substantial amount of energy. What you can say is accelerating from
say, 1000RPM to 6000RPM takes x amount of energy and will take a
certain amount of time - reducing this time requires supplying more
energy per unit time which is what we see on the road when you increase
the 'power'.

[ZeroK66]

There must be a formula, the figure certainly is not fixed - as you say probably not a fixed percentage either... where is Dr-Al.

[DavidT]

RR discussions are off topic here guys.

[viperbl]

I think its gotta be KO4/RS6's then ...

Dam engine has still not been pulled!! I should have pushed it over to the UK and down to MRC, would have been quicker at this rate!!!

[MarkB]

I think its gotta be KO4/RS6's then ...

Dam engine has still not been pulled!! I should have pushed it over to the UK and down to MRC, would have been quicker at this rate!!!

I hope they are charging you a rate that reflects their speed!

[viperbl]

I hope they are charging you a rate that reflects their speed!

Nice thought but somehow I doubt it ... heading down tonight to attempt to chase it ... and the make matters worse the mechanic who has worked on my car before is off on holiday tomorrow ... how selfish