I had my car dynoed at APS today in order to increase the 'sample rate' of cars dynoed. Anyway, now we have 3 cars (with the Hi-tech exhasaut) done on the same dyny over a period of one week.

Here are the specs of my car as it was when dynoed:
- 350Z Track
- 9,600km on the clock
- Hi-tech exhasut (since 1,200km)
- K&N filter (since 1,200km)
- OME 18 Track wheels
- OME 245/45/18 tyres at the rear @ 35psi (cold)
- Running on Optimax fuel (since new)

Interesting thing is not that I dynoed 162kW @ rear wheels, but that the power peak is at around 6,500rpm. That (I guess) shows that the exhaust did what I wanted it to do ie. increase the power over the last 1000rpm of the rev-range and move the power peak closer to the red-line.

Here's the dyno plot from the APS dyno:

 

what is the difference with Shoot Out mode and not?

 

Shoot out mode (software) normally reads a tad higher than the normal (older DD dyno software).

Peter

APS

 

Well that make me feel a little bit better 7kw differerence, I knew mine was always on the low side must have been built on a Monday morning, I believe another dynoed at 159kw.

DavidC

 

Here's the output from my test done 30 minutes later.



There is an interesting little hump right at the peak on David's that I didn't have. We discussed the likelihood that it could have been his K&S air filter (mine is stock).

It was an interesting experiment to get a baseline of sorts on your car, for what it's worth. A pity we couldn't watch, Peter couldn't allow us into the factory for safety/insurance reasons, while that was disappointing it was understandable. I had high hopes of getting the car on AVI in full song but alas it was not to be.

Jim

 

162kw well done David, thats a bitmore like it. So presumably you should be able to push ~173rwkws with the Unichip.

EDIT: Just noticed they've got RPM on their charts!! Bastards

 

Still nowhere near 170kw+ as per Sydney dyno's

David

 

Makes me wonder if APS wants to increase their sample size by dynoing sydney cars. I'm willing to do it when I'm down in melbourne in around 4-5 weeks

By the way my car is stock except the intake and has done 23,000km

 

Jim great to meet you today and thanks for making your Z car available to APS in order to collect some further power data..............as discussed we will most likely organise a tech day for 350 Z Melbourne base members (and anyone else who would like to attend) and we will take out the necessary liability insurance so that members can view the cars being dyno'd, sorry we don't have customers in the dyno room for safety and insurance reasons.

Peter

APS

 

Yeah but you can't compare Melbourne to Sydney

 

Still nowhere near 170kw+ as per Sydney dyno's

I don't think you can compare power readings from one dyno to another. Which means that you can comapre with mine and Sundog's as we were all done on the same dyno.

Have the Sydney dynos been done on the same dyno, or was each different? I'm wondering what the variation on the same duno is as on the APS dyno with the 3 cars we all fit within 7kW range.

There is an interesting little hump right at the peak on David's that I didn't have. We discussed the likelihood that it could have been his K&S air filter (mine is stock).

I was looking at the readings a bit more, and what I find even more odd, is how much the power readings vary between 4000 and 6000rpm. Look at this (me vs sundog):
- 2000rpm = 55 vs 55kW
- 3000rpm = 80 vs 80kW
- 4000rpm = 113 vs 109kW
- 5000rpm = 144 vs 138kW
- 5300rpm = 150 vs 143kW
- 5600rpm = 155 vs 150kW
- 6000rpm = 159 vs 153kW
- 6400rpm = 161 vs 159kW
- 6500rpm = 162 vs 159kW

So, no difference until 4000rpm, then this 'difference grows to about 7kW (max) between 4000 and 6000rpm. And then the 'difference' gets smaller where we have only 2 - 3kW difference at the peak.

I wonder if that is just a difference between cars?

ps. I'd love it if Peter could chime in here and let us know how the 350Z dyno-reading compares to other cars out there (ie. what peak do they hit on your dyno)? Cars of interest would be:
- XR6-T
- Commdore SS
- HSV cars
- Porsche 911
- Boxster S
- WRX
- STi
- S15 200SX
- and anything else you've got handy

 

Dave you should be able to get some of those readings from the unichip dyno chart section on their website.

http://www.************************/un...lications.html

Under commodore they have:

300kW GTS GenIII
VT SS
VT GTS
VT 220 kW GenIII 5.7L - This gets 155kw stock according to the chart.
VT R8 250 kW GenIII 5.7L
VT 5L
VS 5L
Supercharged VT 5L
VL 3.0L Turbo

Some of the graphs actually look different so they might be using older dyno software or different dyno altogether so same rules may apply. i.e. Direct comparison might not be 100% accurate.

 

DavidM, You don't need much of a variation in the engine, or fuel quality to see + - 3 to 4 kW's from engine to engine, I'd guess the small power variation will be due to air/fuel mixtures (you only need a small difference in fuel pressure for this to be the case) though there are many other reasons for power variations such as wheel alignment, this alone can also impact on power readings by up to 10 kW's.

With regard to dyno power readings of other cars you can really only compare cars which run in the same test software, 6 cyl engines are tested in shoot 6 dyno software. To give you guys a good comparison the XR6T (with manual trans) will produce approx 190 to 200 RWkW's once the engine is fully run in.

Peter

APS

 

Not that you can draw any conclusions about how quick the car is from that figure. We all know the real story.

 

Well your correct of course............because Melbourne has been voted the most liveable city on the planet 3 times.


Regards

Peter

 

Just the place for a coupe!

Freeze yer ***** off or dump on yer!

Should never have water restrictions!

 

Some of the graphs actually look different so they might be using older dyno software or different dyno altogether so same rules may apply. i.e. Direct comparison might not be 100% accurate.

Yeah, you're right ... I just was interetsed to see if there's a relation between different cars in the same dyno. I did not realize that the dynos use different 'programs' for different cars (as Peter pointed out).

I often heard the figure of 130k atw thrown around for an STi and 100kW atw for the WRX.

To give you guys a good comparison the XR6T (with manual trans) will produce approx 190 to 200 RWkW's once the engine is fully run in

That's interesting. If I comapre that to our 350Z with Hi-tech readings, then the XR6-T looks to have 30 - 35kW advantage (taht is if the figures are at all comparable). My understanding is that the XR6-T is claimed at 240kW (at the crank), but this is using some 'alternate' standard. If you convert that to the regualar 'standard' that everyone else is using, then the XR6-T will transtate to 230kW or so.

So I was expecting the XR6-T and 350Z (even stock) readings to be closer. Again, nt sure if one can compare between cars like that, but I'd pressume that one can't as the programs used are different and also each car willprobably 'react' differently to the dyno in terms of the measurments.

 

I was thinking the XR6-T had too much at the wheels compared to the V8 comodore or 350z.

240kw down to 190kw - 20.8% loss
220kw down to 155rwkw - 29.5% loss
206kw down to 147rwkw - 28.6% loss

 

Dave you should be able to get some of those readings from the unichip dyno chart section on their website.

I had a quick look through there and here are some cars of interest and their power readings (in the bracket aproximate claimed figure at the crank):

MX5 1.8L (105kW) = 65kW
Magna 3.5L (155kW) = 97kW
WRX '96 (155kW) = 99kW
WRX '01 (160kW) = 104kW
S14 200SX (147kW) = 104kW
Audi S3 (160kW) = 105kW
Audi TT (160kW) = 105kW
Falcon (4.0L) (168kW)= 105W
WRX '99 (160kW) = 106kW
BMW 330ci (170kW) = 115kW
S15 200SX (147kW) = 117kW
Commodore VS 5.0L (175kW) = 122kW
STi '99 (200kW) = 126kW
Commodore VT 5.0L (175kW) = 127kW
STi '02 (195kW) = 133kW
Commodore VT 5.7L (220kW) = 155kW
EVO 6.5 (205kW) = 157kW
HSV 5.7L (250kW) = 190kW
HSV GTS 5.7L (300kW) = 225kW
966 TT (306kW) = 228kW

Again, not sure how comparable are these agaisnt each other, but it they are it seems that:
- S14 200SX was undarated by about 10kW, while the S15 200SX more like 20kW.
- EVO 6.5 was underated by about 20kW.
- Interesting how much losses there seem to be at the dyno for the 300kW cars .. it's like 30%.

 

David you can't really compare rear wheel figures to flywhel figures (car to car) as drivetrain loss varies depending on the transmission and the particular style of drivetrain in the car. And drive train power loss it's not a % as many people think it's much closer to a constant value - that is the drivetrain loss.

In addition the power loss (power measured at the wheels) is not all drivetrain loss as the dyno requires approx 15 Kw's of power to be driven. For example if a car has 240 kW's flywheel (and measures approx 190 kW at the tyres) you need to deduct approx 15 kW's for retarder loss and the balance (35kW) is the approx drive train loss. Hope this helps you understand more about chassis dyno readings.

Bottom line if the power measurement is accurate and you gain an additional 10kWs of power at the tyres you will have a quicker car, the key here is to achieve accurate power measurement from the chassis dyno.

Peter

APS