Mach V Dyno Day preliminary results [long]
04-14-2001, 08:47 PM
#11
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ECU cannot accurately calculate torque.
Yes, there's an internal ECU value that's estimated based on change in engine/vehicle speed (?), but I think the consensus is that this internal calculated torque number doesn't correspond well to any real-world numbers.
--Dan<ul><li><a href="http://www.machvw.com">Mach V Motorsports</a></li></ul>
--Dan<ul><li><a href="http://www.machvw.com">Mach V Motorsports</a></li></ul>
04-14-2001, 09:11 PM
#12
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Sorry, you are not correct in that assumption Dan! - updated
The drive train loss is the SAME for both cars! Check out Audi's information on the cars. The Same multiplier is used for both cars, 1.15. The FronTrak and the TTQ are both Frontwheel drive until the rear wheels slip. You are losing the SAME amount in the drivetrain in this case. Just because the rear wheels are on a roller does not mean you are transferring torque to the rear wheels!
Forgetting about the chips for a minute. How can a STOCK FronTrak produce 7 more hp than an exhaust alone? Then when you add in a chip, you should be even HIGHER! Something is not right here.
Also how can Dave and Michael with identical setups have a 6 hp difference? Also does not make sense.
You have a problem in how you ran your tests.
Forgetting about the chips for a minute. How can a STOCK FronTrak produce 7 more hp than an exhaust alone? Then when you add in a chip, you should be even HIGHER! Something is not right here.
Also how can Dave and Michael with identical setups have a 6 hp difference? Also does not make sense.
You have a problem in how you ran your tests.
04-14-2001, 09:15 PM
#13
Don't know much about this stuff, but I tend to agree with you
Ivan. Even taking into consideration Dan's answer to your post...sorta looks like we're doing okay just the way we are. No flames please, just my preference. And, I'm sure there will be further interpretation of the charts, which will be interesting to see.
04-14-2001, 09:28 PM
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All right, you're getting me torqued off. (Pun intended.)
>The drive train loss is the SAME for both cars!
Whatever you say. All I can tell you is what I have observed, and that is that on a Dynojet inertial dyno, a FWD car has a higher wheel horsepower rating than an AWD car of the same type, and that includes Audi TT's.
(Why would this be? Since BOTH rollers on the dyno have mass, the AWD TT must spin both rollers. On a real road, the AWD car can drag its rear wheels around, only driving its fronts, since the rears maintain the same speed. So, on-road drivetrain loss IS the same as a FWD car. But on the dyno, the rears are at rest, and as the fronts start to turn, the rears are forced to turn as well because of the immediate speed differential.)
>You have a problem in how you ran your tests.
Nope. I have no problem at all with the numbers we saw today. To me these aren't "tests." I'm not trying to prove or disprove any hypothesis here, I'm just reporting numbers that happened on the dyno today. These numbers are FACTS. Interpret them however you like.
My joking title aside, where do you get off saying "You have a problem in how you ran your tests"? You can come down and strap some cars to the dyno yourself to show me how it's done, if you like.
My goal in posting these numbers is to give REAL, OBSERVED DATA on REAL CARS. I see this as a public service; there's all too much made-up, estimated, or interpolated performance data out there, and I think real-world data makes for much better, more-informed discussions.
--Dan<ul><li><a href="http://www.machvw.com">Mach V Motorsports</a></li></ul>
Whatever you say. All I can tell you is what I have observed, and that is that on a Dynojet inertial dyno, a FWD car has a higher wheel horsepower rating than an AWD car of the same type, and that includes Audi TT's.
(Why would this be? Since BOTH rollers on the dyno have mass, the AWD TT must spin both rollers. On a real road, the AWD car can drag its rear wheels around, only driving its fronts, since the rears maintain the same speed. So, on-road drivetrain loss IS the same as a FWD car. But on the dyno, the rears are at rest, and as the fronts start to turn, the rears are forced to turn as well because of the immediate speed differential.)
>You have a problem in how you ran your tests.
Nope. I have no problem at all with the numbers we saw today. To me these aren't "tests." I'm not trying to prove or disprove any hypothesis here, I'm just reporting numbers that happened on the dyno today. These numbers are FACTS. Interpret them however you like.
My joking title aside, where do you get off saying "You have a problem in how you ran your tests"? You can come down and strap some cars to the dyno yourself to show me how it's done, if you like.
My goal in posting these numbers is to give REAL, OBSERVED DATA on REAL CARS. I see this as a public service; there's all too much made-up, estimated, or interpolated performance data out there, and I think real-world data makes for much better, more-informed discussions.
--Dan<ul><li><a href="http://www.machvw.com">Mach V Motorsports</a></li></ul>
04-14-2001, 09:40 PM
#19
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By the way...
...I mentioned to most (but not all) of the Dyno Day participants that I'd post an update online with the results. If you participated, and DON'T want your name or figures printed for any reason whatsoever, just let me know.
--Dan<ul><li><a href="http://www.machvw.com">Mach V Motorsports</a></li></ul>
--Dan<ul><li><a href="http://www.machvw.com">Mach V Motorsports</a></li></ul>
