B7 RS4 Rolling Road Day 18th April 2009 (Free of Charge)

[ArthurPE]

all 4 graphs make ~ the same RAW power at 40 mph (145 or so, the lowest being dubs at 140)), the cf's are different for the cars at this speed
Oli 0.22
Dom 0.25
P_G 0.30
dubber 0.29

You lost me at this point - can you put into (very) simple words please!

the wheel HP measured (actually it measures torque and calculates HP) by the dyno was the same (within 2HP from the average) for all 4 cars...but they each had a different correction factor for some reason...

so using the average wheel HP of ~145...if you use P_G's cf that equals ~188 at the crank...if you use Oli's that equals 177, >6% difference...for the same measured power....

[RI_RS4]

Arthur,

comparisons at 40 MPH on a 3rd Gear pull are useless. RPM and airflow is low at this point in the curve. The throttle body is only open 50% at this point. Where you will see differences is in the "boost" that occurs between 4500 and 5500 rpm, when the short intake runner is switched in and (in some cases) the intake power flap is opened. In dubs case I believe he'll find a massive timing pull, either an intake restriction or obstructed flow at the valves. Something was not right with this engine when it when the throttle body opened.

[ArthurPE]

Arthur,

comparisons at 40 MPH on a 3rd Gear pull are useless. RPM and airflow is low at this point in the curve. The throttle body is only open 50% at this point. Where you will see differences is in the "boost" that occurs between 4500 and 5500 rpm, when the short intake runner is switched in and (in some cases) the intake power flap is opened. In dubs case I believe he'll find a massive timing pull, either an intake restriction or obstructed flow at the valves. Something was not right with this engine when it when the throttle body opened.

40 mph in 3rd at at the engines peak output...~100% torque...
in fact for the 4 dyno charts I analyzed, it was peak torque...

HP is not a force, it's a measure of the rate of application of force...torque is a force and the instantaneous output of the engine...

although airflow DP is ~ velocity (actually v^2), the main points of pressure drop in an engine are the filter, and more so the throttle, hence the vaccum going to 0 when it's opened...other drops are minor...

and regardless, the engine will inhale ~ the same volume (for a given engine), it will just lose a bit more in pumping losses...

how can I upload an xls spreadsheet?

[klauster]

here is mine

[rAudiguy]

Has everyone had there print out's now??

thanks

Jim

[RED_ROCKET]

Still waiting for mine...

[PetrolDave]

Don't know if this is OT or not - doesn't the ECU SW restrict the throttle opening to 70% of max in 1st, 2nd and 3rd gears? I think I've read that here and elsewhere.

If so, are results in 3rd gear representative of the actual maximum power output? Wouldn't results in 4th be needed?

[pippyrips]

Has everyone had there print out's now??

thanks

Jim

Still waiting on mine.

[pippyrips]

Don't know if this is OT or not - doesn't the ECU SW restrict the throttle opening to 70% of max in 1st, 2nd and 3rd gears? I think I've read that here and elsewhere.

If so, are results in 3rd gear representative of the actual maximum power output? Wouldn't results in 4th be needed?

Yep, vagcom scans show 51% throttle up until 5500rpm on stock cars, that is why the healthy cars show a jump in power around this mark on the graphs.

In theroy it doesn't matter as you are measuring peak power which in the they get to.

[ArthurPE]

Don't know if this is OT or not - doesn't the ECU SW restrict the throttle opening to 70% of max in 1st, 2nd and 3rd gears? I think I've read that here and elsewhere.

If so, are results in 3rd gear representative of the actual maximum power output? Wouldn't results in 4th be needed?

if this is true, it would limit power...less air=less fuel=less power...

this would explain why torque makes spec at low rpm, ie, when the air volume is satisfactory, and as rpm's climb, HP tails off...

very interesting...

perhaps what the modified ecu mapping does is allows full throttle in < or = 3rd gear? therefore full power...

[pippyrips]

Don't know if this is OT or not - doesn't the ECU SW restrict the throttle opening to 70% of max in 1st, 2nd and 3rd gears? I think I've read that here and elsewhere.

If so, are results in 3rd gear representative of the actual maximum power output? Wouldn't results in 4th be needed?

if this is true, it would limit power...less air=less fuel=less power...

this would explain why torque makes spec at low rpm, ie, when the air volume is satisfactory, and as rpm's climb, HP tails off...

very interesting...

perhaps what the modified ecu mapping does is allows full throttle in < or = 3rd gear? therefore full power...

Not all mappers do this, there were a few mapped cars at the RR day that delivered 'standard' curves if you know what i mean

Weridly, Jim's car seemed to have redeveloped its throttle restriction at the RR day even though it had been removed previously.

I think this is what most people notice when their car has been mapped and the throttle sorted. They don't actually gain many if any more horsepower but it feels like you have as you get more of them early on!


Mine is now fully open in all gears and the difference off the mark is really noticable, its also now very easy to drift the tail on roundabouts

[bn8959]

Still waiting for mine too

[mac4RS]

Still waiting for mine too

Me too...

[pippyrips]

I gave Paramount a ring yesterday and got mine via email a few hours later. Might be worth doing the same if you are still waiting.

[youry]

We at RS QUATTRO (Belgium) is exactl what we do in our ECU mod, we modify the intak valve limitation in firt three gears, this is huge difference in driving. we don't put the limitation to 100% though as its also a protection for the clutch, but increasing it is a myst ansd to be honest is probably one of the main reasons why an ECU remap is worth it....

more info on www.rsquattro.com