How Much Rear Kws = 300kws At Fly

[andypower5.7]

Can someone tell me to get 300kws at the flywheel how much do you need to have at the rear.

[SS Enforcer]

There are a lot of variables but if you have 230 odd rwkw you probably have 300 fwkw. This is not gospel but a reasonably close estimate.

It's the sort of question gaurenteed to start a flaming debate. :bawl:

cheers

[mustanger]

Roughly 235rwkw for a manual

[Wonky]

Manual or auto? Autos lose more through the driveline and A6 are worse than A4. If you :search: the question on conversions has only been asked a million times before...... I've seen figures been 20% and 30% quoted but it varies depending on various factors. Of course it also depends on dyno used to measure it on as I've seen over 30rwkw difference on the same approx 250rwkw car on different dynos.

[cvy57l]

300KW at flywheel is about 230KW at the wheels:)

[planetdavo]

Type in "rwkw" or "fwkw" into ANY of this forums search functions, and you will get handfuls of answers.
This question has been done to death.

[cbwolf]

Well, the last STOCK VE GTS that i saw dynoed made 212RWKW and they're meant to have around 307FWKW.

[Wonky]

I've seen figures been 20% and 30%....
:doh: * between!! :doh:

[Spectrum]

I've also seen someone quoting ONLY 17% losses, which makes 300FwKw 249RwKw....

hmmmmmmm..

[SIG-054]

just chuck a stock VT-VY GTS on the rollers and there ya have it. :)

[cbwolf]

Well, the last STOCK VE GTS that i saw dynoed made 212RWKW and they're meant to have around 307FWKW.

Expanding on my previous post, a stock VE GTS is meant to have 307 FWKW and it was dynoed at 212RWKW.

So, the difference is 95KW, which equates to 30.9% loss from 307KW. So in general, i think a figure of around 30% drive train loss is a good guide.

This was by the way performed on a famously "accurate" dyno, not one of those happy happy joy joy dyno's some workshops use to inflate their customers' genitals.

[MclarenF1]

I can answer this question based on an artilce in Motor magazine based on the current VE V8 range. All dyno test were done on a Dyno Dynamics AWD dynomometer at 16 degrees at a Victorian tafe college. The results are shocking. There is not much power difference between a GTS and an SS.

HSV GTS manual-flywheel 302KW, Claim 307KW,RWKW 245
R8 auto-flywheel 299KW, Claim 307KW,RWKW 243
SS manual-flywheel 292KW, Claim 270KW,RWKW 236
SSV auto-flywheel 285KW, Claim 270KW,RWKW 232
Force 8 auto-flywheel 282KW, Claim 290KW,RWKW 229
Force 6 auto-flywheel 275KW, Claim 270KW,RWKW 229
XR6 turbo auto-flywheel 236KW, Claim 245KW,RWKW 195

[awddynotodd]

I can answer this question based on an artilce in Motor magazine based on the current VE V8 range. All dyno test were done on a Dyno Dynamics AWD dynomometer at 16 degrees at a Victorian tafe college. The results are shocking. There is not much power difference between a GTS and an SS.

HSV GTS manual-flywheel 302KW, Claim 307KW,RWKW 245
R8 auto-flywheel 299KW, Claim 307KW,RWKW 243
SS manual-flywheel 292KW, Claim 270KW,RWKW 236
SSV auto-flywheel 285KW, Claim 270KW,RWKW 232
Force 8 auto-flywheel 282KW, Claim 290KW,RWKW 229
Force 6 auto-flywheel 275KW, Claim 270KW,RWKW 229
XR6 turbo auto-flywheel 236KW, Claim 245KW,RWKW 195

And a $2 Calculator will show you that an across the board 20-21% is simply added to the RWKW numbers in that article, very scientific, but hey, it sells magazines.

[cbwolf]

lol, Motor magazine. What a bunch of retards. I'd take anything i read in that magazine with a grain of salt.

I'll bet you anything you like, that the plebs from Motor did NOT pull the engine out of each of those cars to put onto an engine dyno to get those flywheel figures.

[SS Enforcer]

Whilst those figures arn't very accurate they could be used as a rough guide for comparisons only.
It wouldn't matter how Motor derived the figures they would be disputed anyway by someone so take em with a grain of salt and don't get too hung up on them.

cheers

[MclarenF1]

lol, Motor magazine. What a bunch of retards. I'd take anything i read in that magazine with a grain of salt.

I'll bet you anything you like, that the plebs from Motor did NOT pull the engine out of each of those cars to put onto an engine dyno to get those flywheel figures.

Yeah like you know better, how the **** would you know wether there accurate nor inaccurate? They put the cars on a chassis dyno measuring flywheel plus real wheel KW's. Why would you call them 'Retards"?, like your ever going to conduct a test like this!

[SS Enforcer]

Chassis dyno can't measure flywheel HP it's just an estimate.

cheers

[MclarenF1]

Chassis dyno can't measure flywheel HP it's just an estimate.

cheers

It is surprising though the chassis dyno is and estimate its unbeleivave the GTS ans SS are so close. Given the fact the GTS is claimed to have 37kw on the SS, the dyno certainly show only a 12kw difference. No wonder in alot of performance tests the SS was quicker in a straight line given it's weight advantage over the GTS:rofl:.

[VXSS346]

All this shows, is that dyno figures mean absolute s***

Its only a peak figure at 100% throttle at one particular RPM.

How it feels to drive, and the spread of torque is much more important and will also add up to much stronger overall acceleration. (MPH on the track)
But that doesn't show up as a high dyno number. So WTF is the point chasing a dyno number???

Variations of 30+ rwkws are seen on the same car. :confused:
Do you really think they can be believed??

My 2c

Merry Christmas all :xmas:

[MclarenF1]

Well i can you one thing, there must not be much of a power difference between the two cars as Motor have not been able to go any quicker with the GTS than 5.2's/13.5's. They have done 5.2's/13.4's with the SS. This to me points toward the GTS not delivering or the SS over delivering in a straight line. I would have thought the GTS with it wider rubber, 3.7 diff compared to 3.45's on the SS would easily have the SS's measure in acceleration terms but it turn out it doesn't. Maybe the fact the GTS is heavier is the defineing facter here. But then again there must be only 40kg in it.

[cbwolf]

Yeah like you know better, how the **** would you know wether there accurate nor inaccurate? They put the cars on a chassis dyno measuring flywheel plus real wheel KW's. Why would you call them 'Retards"?, like your ever going to conduct a test like this!

lol,

Firstly, as SS Enforcer said, a chassis dyno can't measure flywheel power. To measure flywheel power, they would have needed to remove the entire engine from the car and set it up on an engine dyno to get a reading. This can take the good part of a whole day for one engine.

Secondly, if you could use a calculator, you'd see that all of the Holden's RWKW measurements simply have 23% added onto them to get the supposed "flywheel" power. Really scientific huh?

Not to mention that chassis dyno's are virtually useless. I'v had my car dynoed at 4 different dynos (3 of them being at sponsors workshops) and i got 4 vastly different figures with a range of 37KW.

And, as i said before, i saw a stock GTS dynoed on what is generally considered one of Victorias most "accurate" dynos and it pulled 212RWKW. Speaking to the owners of that workshop, they informed me that figure is about average for the new VE HSV's.

Also, Dyno Dynamics dynos are known to be a bit figure happy, and that's taking out any error or lack of ability of the person conducting the run.

[MclarenF1]

I'm not so much amazed by the RWKW's but the fact the GTS is not faster than an SS in a straight line, it a bit of a disappointment. I was planning to get either an R8 or a GTS as my next set of wheels in a few years but the fact there is not much in it in a straight line drag i wonder whats the point.

[cbwolf]

Well this thread was about flywheel to rearwheel kw conversions.

But if the figures you posted are correct, it is a little disappointing. I'd put it down to the extra weight of the GTS over the SS (Approx. 60kg) and the extra weight of the 20" wheels over the SS 18".

I know that i definately felt the difference when i fitted my 20" wheels. Unsprung weight = evil.

Kind of reminds me of when Holden released the Supercharged V6 and it turned out to be more powerful and faster then the old 5L V8's. Talk about being red faced.