Forum Rolling Road day @ Superchips 6th June 2009

[Phil Mcavity]

My querry has always been, that intake temps have been taken from inside the car, which may tend to affect the TFSI/TSI engine calculations.

I think you need to go back and read Jamie's reply again Steve as your statement about the intake temps being taken from inside the car is incorrect.

Inlet temp is measured by the dyno over obd, we do this to achieve consistency

oks, but why are the temps so different between cars??

im intrigued, and confused!.

Be good to see other cars results ie, other Brands to see if say for example, it produced simular pattern of results maybe from other RR days.

[Hurdy]

i was only making an example john as your car has shed loads more done modification wise over Dominics.You like me, would of thought you would have more power achieved when the ammount of mods youve done. You should of got the Most on the day.

Im not trying to single anyone out john.In my case, my car as an example does not produce 254bhp!

Don't worry about it Steve, I was only trying to add to your suggestions as to reasons why there are differences in results

[WhiteGTI]

Am I understanding this correctly....because my intake temps are very high the rolling road is compensating much more for it (to bring it to a crisp spring day as Jamie says), therefore meaning that my power numbers are higher as a result of more compensation? 

[Hurdy]

Am I understanding this correctly....because my intake temps are very high the rolling road is compensating much more for it (to bring it to a crisp spring day as Jamie says), therefore meaning that my power numbers are higher as a result of more compensation? 

More or less...yes.

[WhiteGTI]

Oh 

So realistically because my wheel hp is lower than Joe's it means that my car has got less power than his?

[Hurdy]

Oh 

So realistically because my wheel hp is lower than Joe's it means that my car has got less power than his?

Not necessarily.

Your engine may have a little more power, but the losses are more significant due to heat soak, intake temps, parasitic losses from other areas like air con, flywheel etc.

Joes will see more power getting to the wheels due to less losses from intake temps and heat soak especially. However the reading point is the wheels so the losses are calculated backwards to get the engine power.

The only MEASURED power is from the wheels.

[WhiteGTI]

Ahh I understand now! Thanks for taking the time to reply John 

[/Goes to find the Thank You button, but it isn't there...]

[Poppa Dom]

Ahh I understand now! Thanks for taking the time to reply John 

[/Goes to find the Thank You button, but it isn't there...]

Geez Chris - what you doing on here before 7am 

[Superchips]

DYNO 102 - I think we are all past 101!

WHP
1. Used commonly by americans because their many of their dyno's do not measure anything else. (worked there for 2yrs)
2. Valid for comparisons on the same car, same day, same dyno.

Transmission loss - more accurately Rolling loss
1. Not so much the frictional losses in the gearbox/diff BUT the double convex deformation of the tyres on the relatively small radius rollers.
2. "Rolling losses" are affected by tyre pressure and manufacturer but ultimately speed, the loss at 100MPH will be over double of those at 50MPH.

If we want to see high WHP we would pump up the tyres nice and hard and run in as low a gear as possible.

Therefore comparisons between two cars' WHP are simply not possible because of the above.

Jamie

[joesgti]

im unsubscribbing to this thread, my heads boggled!! 

my car is rapid, it feels rapid and goes like stink (ask tom  ) and im happy with my results,   

[Hedge]

my car is rapid, it feels rapid and goes like stink (ask tom  ) and im happy with my results,   

That hits the nail on the head for me. 

[Andy]

think its ok to get numbers on the rolling road but for me,its how the car performs on the road that counts

[Hurdy]

my car is rapid, it feels rapid and goes like stink (ask tom  ) and im happy with my results,   

That hits the nail on the head for me. 

Yup, sounds about right to me

I didn't know you could get a higher whp just by pumping your tyres up though

*** reminder to self - 50psi at the next RR day ***

[SteveP]

Ok, Here are the results in a nice handy table 

I will add links to the graphs and correct any mistakes over the next few days 

http://www.mk5golfgti.co.uk/RRDay2009.html
 

[winrya]

Thanks, that's really useful.

Really pleased with mine, especially the torque, for just a map i knew it was running lovely but that's a great result.  308lb ft

Oh, and it was 250.9bhp