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
I noticed that one and was wondering whether it was a true measure of transmission losses or a calibration problem?bam_bam wrote:Drag power 254.2 -
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
HA!Doug_S2 wrote:Is that really your Reg number?
YupDoug_S2 wrote:Is that really your Reg number?
Users browsing this forum: No registered users and 83 guests