you can see the applied correction factor 0.794 in the picture. It seems very low. A quick calculation from the temperature and pressure figures I know give a correction factor of 0.975 which would make a huge difference to the figures displayed.

Bottom line is that dynos can lie!

__________________
KiDo Racing - your choice for coilovers and high performance brake kits

Because STOPPING is never optional.

http://www.perth-wrx.com/vb/kido-racing/

www.kido-racing.com.au

out of curiosity, whats the x-axis on the graph?

__________________
MY93 Impreza GX 1.8L, 0hp, 0nm

EDIT:Sorry to hi-jack,

DD and Mainline are great equipment, with a lot more accuracy than most can imagine. Except for the correction factor part mentioned which can be abused by the operator and tyre pressures that Rossco mentioned.

My 2010 Dynapack 5000 does not allow for operator correction factors (EDIT:this is done automatically via Dynapack's software) due to Dynapack's current approach.

The torque mentioned in the pic was uncorrected torque that the DD read. The operator did not choose the right torque parameter for the screen readout, which can be changed with the click of a button -- nothing to do with the inaccuracies of the dyno in this case, except operator error.

the X-axis is time. 0 being now and 20 being 20 seconds ago.

Thats not a hi-jack Mao, the Mainline I know a little about and are very respected. The DD I am not familiar with but then I am far from being a dyno expert. The one draw back of a hub dyno from the owners perspective is the additional time required to fit a car on it, and as we know time is money.

I should also mention that ramp rate is another operator fiddle which can affect the power & torque readings particularly on a high powered turbo car.

__________________
KiDo Racing - your choice for coilovers and high performance brake kits

Because STOPPING is never optional.

http://www.perth-wrx.com/vb/kido-racing/

www.kido-racing.com.au

This thread has gone in a direction of discussing dynos instead of tuning. Everyone know different dynos read differently. Just stick to one dyno to see the differences between different tunes.

Street tuning can be done well if enough time is taken. Rosscos tune I think shows this well. All done by him and that dyno readout of him from Mao's dyno is one of the smoothest I've ever seen. I'd be interested to hear of the cons of street tuning vs dyno. Unfortunately my MY99 can't be tuned using open source software

Adi

Sent from my GT-I9100 using Tapatalk 2

Street tuning cannot beat the repeat-ability of a dyno, the ability to hold the same identical RPM for minutes etc. Also a dyno is much less likely to crash into the back of a truck while you're squinting at a laptop

__________________
MY93 Impreza GX 1.8L, 0hp, 0nm

Also, you should only street tune if you have a bright green Mitsubishi Eclipse with lots of NOS...

Silly F&F.

__________________
MY01 JDM EVO VII - 230KW / 430NM @ 1.6BAR

The only two differences I have seen between dyno tuning and street tuning is that dyno pulls are usually done in 4th and street pulls in 3rd, and after a dyno tune the tuner takes the car for a drive on the street.

I have never seen a dyno tuner hold a steady RPM.
Also worth noting, you should never be looking at the laptop while driving. Ever! There is no need, and as you pointed out, the back of a truck is something to avoid at all costs.

__________________
KiDo Racing - your choice for coilovers and high performance brake kits

Because STOPPING is never optional.

http://www.perth-wrx.com/vb/kido-racing/

www.kido-racing.com.au

I Log-> Review-> Alter -> Log -> Review and so on.

__________________
[CENTER][SIGPIC][/SIGPIC][/CENTER]
[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]

Back onto the price issue...

Surely as a tuner who has tuned lots of different subaru's you would have a build up of stored tuning maps etc for other cars with similar mods? would this not also effect the price or will the tuner still charge more due to there being more mods even if there is a map on his computer?

Would there be any more to change on a map for a tuner between a bug eye with a vf34, sti top mount and exhaust that he has done 300 times than a std wrx? just food for thought as I'm sure he won't be starting from scratch every time..

however i'm no tuner so may be completely wrong..

__________________
Twin Scroll GC8 DCCD FTW... tune and on road shortly!!