How many RWKW do you have with what mods?

Engines, Transmissions & Final Drive questions and answers

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oztrackdays
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Power the answer ... depends on the question.

Postby oztrackdays » Thu Jun 12, 2014 11:46 am

I will admit to being guilty of only liking cars capable of decent "bursts" of acceleration a car that is all handling
and no power doesn't really work for me as more mundane cars get comical levels of power being satisfied
with < 150 rwkw per tonne is becoming more difficult to perceive as "fast" at least to me anyway.

I had the 270 kw SS Ute and I never felt it was fast as it had 2 tonne of Dunnydore to motivate.

the 200 awkw STI my partner had felt nice.

My BRZ is numb and slow it makes around 100 rwkw and weighs 1200+ kg, it is comfy driving in a Canberra winter with heated leather seats though.
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Novice1
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Re: How many RWKW do you have with what mods?

Postby Novice1 » Thu Jun 12, 2014 1:06 pm

I could start a new post. However, I am sure someone will be able to answer my query re power made ar rear wheels.

eg Nc 1quoted 118 kw at the engine. On the dyno 92 kw atw seems to be average.

Subaru brz 147 kw at the engine, but last poster quotes 100 kw atw.

Given drivetrain losses are normally quoted as

Fwd 10 % drive train loss
Rwd 15 % drivetrain loss
Awd 17 % drivetrain loss

It would seem the above drivetrain losses are excessive.
Are the quoted figures for new cars exaggerated or are drivetrain losses more substantial than 10-17 %.

Cheers Novice1

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Re: How many RWKW do you have with what mods?

Postby Nevyn72 » Thu Jun 12, 2014 1:18 pm

Factory figures (at the engine) are for a brand new engine in optimal conditions with no accessories hanging off.
So in addition to drive train losses you will need to add drag from things like power steering pumps, AC compressors (drag even when not running), alternators under load, etc.
On top of this you have other factors such as conditions at the time of testing, wheel/tyre choice, wear on the engine, the dyno itself, etc......

I've always believed you should be looking for ~30% loss from the 'factory' figure in the real world. :wink:
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Lokiel
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Re: How many RWKW do you have with what mods?

Postby Lokiel » Thu Jun 12, 2014 1:25 pm

I'm betting the unexpected discrepancies are because the flywheel figures quoted are for a pre-production engine under ideal circumstances with none of the emission control crap involved - bigger numbers look better.
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oztrackdays
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I call it "at the brochure" kw

Postby oztrackdays » Thu Jun 12, 2014 2:52 pm

The BRZ is posted as 147 flywheel Kilowatt I feel the real number is more like 130-140

my 101 rwkw dyno chart is from a hub dyno which often read lower than rolling road dyno's.

the real test is how quickly it builds speed and it basically doesn't :(
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Novice1
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Re: I call it "at the brochure" kw

Postby Novice1 » Thu Jun 12, 2014 5:06 pm

oztrackdays wrote:The BRZ is posted as 147 flywheel Kilowatt I feel the real number is more like 130-140

my 101 rwkw dyno chart is from a hub dyno which often read lower than rolling road dyno's.

the real test is how quickly it builds speed and it basically doesn't :(


Yup having dríven the toyota 86 I wud buy a turbo version one, expected release date 2016.

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speed
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Re: How many RWKW do you have with what mods?

Postby speed » Thu Jun 12, 2014 10:17 pm

x2 re 30% loss.


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NA6 turbo - 140kw atw - not the most powerful but so much fun :D

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How many RWKW do you have with what mods?

Postby speed » Thu Jun 12, 2014 10:17 pm

x2 re 30% loss.


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Sorry tapatalk posted twice!
NA6 turbo - 140kw atw - not the most powerful but so much fun :D

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Re: How many RWKW do you have with what mods?

Postby Sage » Wed Jun 25, 2014 10:36 am

1.6
Big Plenum
Big Intake
No mechanical water pump
Extractors to 2" exhaust
Adjustable CAM gears (factory cams).
Adaptronic ECU

82kw at 7900rpm.

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Re: How many RWKW do you have with what mods?

Postby rascal » Wed Jun 25, 2014 1:29 pm

Sage wrote:Big Plenum

Got any details and/or pics?

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david_syd_au
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Re: How many RWKW do you have with what mods?

Postby david_syd_au » Wed Jun 25, 2014 2:03 pm

NB8A 1.8
No cat (race car) and Mazspeed muffler. Otherwise stock exhaust system.
Driver's side short air intake with MAF removed
Megasquirt2 PNP
83.4 RWKW
2011 NC LE "Black Beauty" (ours) | 2006 NC race car "Shazza" (his) | 1998 JDM NB race car "OMG" (hers) | NC Trailer

speed
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Re: How many RWKW do you have with what mods?

Postby speed » Wed Jun 25, 2014 8:42 pm

Sage, that's some awesome power from a na6.
Wonder how much the plenum, intake and cam gears give.
Not for me as I'll probably turbo in a couple if months but curious all the same :)


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NA6 turbo - 140kw atw - not the most powerful but so much fun :D

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Re: How many RWKW do you have with what mods?

Postby speed » Wed Jun 25, 2014 8:44 pm

david_syd_au wrote:NB8A 1.8
No cat (race car) and Mazspeed muffler. Otherwise stock exhaust system.
Driver's side short air intake with MAF removed
Megasquirt2 PNP
83.4 RWKW


I'm green with envy. Amazing how much difference that extra 200cc makes.


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NA6 turbo - 140kw atw - not the most powerful but so much fun :D

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Re: How many RWKW do you have with what mods?

Postby Sage » Thu Jun 26, 2014 11:38 am

Yeah she goes real well. Hoping for a little bit more out of her. I have a suspicion she has some mild head work too.

Pic of the plenum. She is a big one :)

Having no mechanical water pump too should help a bit. (has an electric water pump instead).

Image

Sage
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Re: How many RWKW do you have with what mods?

Postby Sage » Thu Jun 26, 2014 11:45 am

i just went back over the last few pages. I should add the Adaptronic is superb to work with and even has Youtube clips from the developers to help you tune your own ride. Its not all secret mens business like a lot of other aftermarket ECUs. Gotta give them credit. I am looking forward to playing around with it. (I only got the car a month ago - still performing some maintenance and cosmetic tasks).


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