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Just had the new motor on the rollers.

The power figure looks good but are the losses, (Drag Power) to be expected?



Just want to be sure that the tester wasn't inflating the result.

Cheers

glug

Unable to see image.

What was the peak power and torque reading.

What type of dyno - dyno dynamics or some other?

Corrected power 706.8
Engine Power 671.5
Wheel power 417.3
Drag power 254.2
Max power at 6350
Max torque at 4035
Torque 904.2nm
Slip, (manual input) 6%
Ambient temp 18.9
IAT 39.8
RH 61.5%
MAHA rolling road at QST.
Cheers
glug

Drag power 254.2 -

bam_bam wrote:Drag power 254.2 -

I noticed that one and was wondering whether it was a true measure of transmission losses or a calibration problem?

Glug, thanks for the post and reply.

The dyno '"experts" i have spoken to with extensive awd dyno experience on a "Dyno Dynamics" dyno with modded turbo subarus, evos, skyline/nissan claim up to 30-35% transmission loss can be expected from awd transmission.

based on say a 35% transmission loss, you engine is making 688 bhp. If your beast is an mtm 700 bhp special, I would say the dyno whp is a little conservative, but the Mustang(?) dyno correction factors make it up to 700 bhp as it should be.

I find the 254 bhp drag power with an engine power of 706 bhp works out to a ~ 60% transmission loss. This is a bit high. I would hazard a guess that your beast was really tied down to the rollers with the rollers loaded more than what you would see in normal road conditions. Not surprising as dyno mishaps are not pretty when the tie down straps let go! http://www.youtube.com/watch?v=OzFGUUR1 ... re=related

For example my APR mapped C6 showed 558 whp on a Dyno Dynamics dyno. Applying a 30% loss, engine power is ~ 750bhp which is a bit high. More like ~700bhp, I believe.

If i applied the drag power of 254bhp, my engine is making 812 bhp, which it clearly is not.

Dyno readings are very variable and depend on setup of the car on the rollers- how tightly it is tied down onto the rollers - very signifcant factor and no one places a strain gauge on the tie down straps for consistency. Also critical is how much load placed on the engine and rate at which load is placed- governed by the operator and the "dyno mode".

For example on a dyno dynamics you can run a C6 in 'shootout 8F mode' or '44 mode'. Results will be diffferent, a function of the load and rate of "braking" applied to the rollers.

What the above shows is that Dynos are ok for relative comparison of vehicles with identical set up on the dyno on the same day, same temperature, same tied down / staic load on the rollers. But dynos of different makes give different readings.

The true test of the engine power and torque your beast is the time to run the 1/4 mile strip.

With 700bhp mtm trim, it should run mid- high 11 seconds, depending on the ambient and track temperature on the day.

This is the reason I asked for fellow RS6 C6 owner quarter mile times in another post, so could see what correlation there was between claimed engine power and quarter mile time.

We know that an APR tuned C6 according to APR will run the quarter mile in 12.1 secs with claimed 665 bhp. http://www.goapr.com/products/ecu_upgra ... c6rs6.html

My beast is APR tuned plus MRC filters and ran 11.9 secs with 89 degF ambient/104 degF track temperature.
So maybe running close to 700 bhp. Should make more power and run faster in May when night time temperatures drop to 60degF.

We have the luxury in Perth of being to run street registered cars and bikes every wednesday night ("whoop ass wednesday") for most of the year on a pro quarter mile strip (with or without passengers). You 'run what you brung' unless go faster than 10 seconds. see http://www.motorplex.com.au/news.php?ne ... 27&g=1&pg=
and see http://www.motorplex.com.au/gallery.php ... 59&pg=drag

So look forward to seeing your quarter mile time and ambient and track temperatures.

Our RS6 C6's are truly awesome vehicles and wil become collectors items with their V10 Lamborghine derived engines.

apologies for the rambling on.

john

Our RS6 C6's are truly awesome vehicles and wil become collectors items with their V10 Lamborghine derived engines.




I like this bit!!!!!!!!!!!!!!!!!!!!!!!

On a snowy December morning....

At Inters on a hot (very) day my C6 ran 11.8s 124mph before I had the GBox mapped.

VBox 0-60mph in 3.74s and 0-100mph in 7.98s.

Had VBox 203mph with more to come but a LOT of distance required to do that, 3 miles plus with ceramics

Thanks for the detailed reply.

The tie down is certainly an element that I hadn't considered.

My main interest was that perhaps the car was not making anything like 700 bhp and the rest of the figures might reveal a scam to make the bhp up to the mtm advertised output, but if you cannot see anything untoward then perhaps I'm just being paranoid

As you say the quarter mile time will reveal all.

Hope you're right about becoming collectors cars as all I can think about is £10k pa depreciation

BTW Perth sounds like my kind of city

Cheers

glug

perthwaRS6 wrote:Glug, thanks for the post and reply.

The dyno '"experts" i have spoken to with extensive awd dyno experience on a "Dyno Dynamics" dyno with modded turbo subarus, evos, skyline/nissan claim up to 30-35% transmission loss can be expected from awd transmission.

based on say a 35% transmission loss, you engine is making 688 bhp. If your beast is an mtm 700 bhp special, I would say the dyno whp is a little conservative, but the Mustang(?) dyno correction factors make it up to 700 bhp as it should be.

I find the 254 bhp drag power with an engine power of 706 bhp works out to a ~ 60% transmission loss. This is a bit high. I would hazard a guess that your beast was really tied down to the rollers with the rollers loaded more than what you would see in normal road conditions. Not surprising as dyno mishaps are not pretty when the tie down straps let go! http://www.youtube.com/watch?v=OzFGUUR1 ... re=related

For example my APR mapped C6 showed 558 whp on a Dyno Dynamics dyno. Applying a 30% loss, engine power is ~ 750bhp which is a bit high. More like ~700bhp, I believe.

If i applied the drag power of 254bhp, my engine is making 812 bhp, which it clearly is not.

Dyno readings are very variable and depend on setup of the car on the rollers- how tightly it is tied down onto the rollers - very signifcant factor and no one places a strain gauge on the tie down straps for consistency. Also critical is how much load placed on the engine and rate at which load is placed- governed by the operator and the "dyno mode".

For example on a dyno dynamics you can run a C6 in 'shootout 8F mode' or '44 mode'. Results will be diffferent, a function of the load and rate of "braking" applied to the rollers.

What the above shows is that Dynos are ok for relative comparison of vehicles with identical set up on the dyno on the same day, same temperature, same tied down / staic load on the rollers. But dynos of different makes give different readings.

The true test of the engine power and torque your beast is the time to run the 1/4 mile strip.

With 700bhp mtm trim, it should run mid- high 11 seconds, depending on the ambient and track temperature on the day.

This is the reason I asked for fellow RS6 C6 owner quarter mile times in another post, so could see what correlation there was between claimed engine power and quarter mile time.

We know that an APR tuned C6 according to APR will run the quarter mile in 12.1 secs with claimed 665 bhp. http://www.goapr.com/products/ecu_upgra ... c6rs6.html

My beast is APR tuned plus MRC filters and ran 11.9 secs with 89 degF ambient/104 degF track temperature.
So maybe running close to 700 bhp. Should make more power and run faster in May when night time temperatures drop to 60degF.

We have the luxury in Perth of being to run street registered cars and bikes every wednesday night ("whoop ass wednesday") for most of the year on a pro quarter mile strip (with or without passengers). You 'run what you brung' unless go faster than 10 seconds. see http://www.motorplex.com.au/news.php?ne ... 27&g=1&pg=
and see http://www.motorplex.com.au/gallery.php ... 59&pg=drag

So look forward to seeing your quarter mile time and ambient and track temperatures.

Our RS6 C6's are truly awesome vehicles and wil become collectors items with their V10 Lamborghine derived engines.

apologies for the rambling on.

john

A few weeks ago at 47,000 miles I took my unmodified car to a rolling road.
579.9bhp at the flywheel and 459.2bhp at the wheels.

Is that really your Reg number?

Doug_S2 wrote:Is that really your Reg number?

HA!

Reg = "FAG 9OT"

In the never ending search for 'reliable' and 'repeatable' power and torque at the wheel numbers, have any UK owners used the "Dynapack Hub Dyno" and advise their whp and torque readings and state of tune?

Home web site: http://www.dynapack.com/

According to the website, UK speed shops that use the dynapack hub dyno are;

http://www.advancedme.co.uk/

http://www.thor-racing.co.uk/Chassis_Dynamometer-23.asp This site has a good FAQ section on how and what a dyno hub test does.

There may be other UK speed shops as well.

I will test my C5 and C6 RS6 here in Perth on the local speed Shop with Dynapack dyno hub and report back on results.

john

Doug_S2 wrote:Is that really your Reg number?

Yup

Only bought it to wind up the P.C. bores at work.

I was banned from the car park for the first week until the union intervened.