Dyno Day at Porsche Exchange
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Originally posted by O-Ace
You guys could dyno at AMS located in Arlington Heights. I think they have an AWD dyno.
-Awais
You guys could dyno at AMS located in Arlington Heights. I think they have an AWD dyno.
-Awais
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Originally posted by MKW
Lou, since you and Stephen both have the same Cargraphic exhaust, and similar level ECU programming from two different companies, is there a way you can post the graphs so we can compare HP tracings and area under the TQ curves ? That would tell us as more than just peak numbers .
Lou, since you and Stephen both have the same Cargraphic exhaust, and similar level ECU programming from two different companies, is there a way you can post the graphs so we can compare HP tracings and area under the TQ curves ? That would tell us as more than just peak numbers .
Stephen
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Hey Tuner gods (Todd and Stephan), please comment on my dyno accuracy concerns. I don't want to sound like a cry baby but I really don't believe what I saw. Please comment on my questions and how LSM's car could read what they said it did.
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Originally posted by MKW
John , I've seen stock Turbos dyno around 360-370 rwhp which implies 12% drivetrain loss IF Porsche's advertised 415 flywheel hp rating is accurate. OTOH, if the stock motor REALLY puts out 425-430 flywheel as I believe , then the drivetrain loss is more like 15% , a typical figure for many high performance sports cars like the Corvette and Viper. Using the latter figure , the Upsolute/Cargraphic car of Stephen Ti ( and yours ) is probably around 455 rwhp divided by .85 = 535 flywheel HP ! Any way you look at it, you are puting down nearly 90-100 hp more to the ground vs stock.
(Of course , we lose about 10 hp stock or modded here in California due to our 91 octane gasoline .)
John , I've seen stock Turbos dyno around 360-370 rwhp which implies 12% drivetrain loss IF Porsche's advertised 415 flywheel hp rating is accurate. OTOH, if the stock motor REALLY puts out 425-430 flywheel as I believe , then the drivetrain loss is more like 15% , a typical figure for many high performance sports cars like the Corvette and Viper. Using the latter figure , the Upsolute/Cargraphic car of Stephen Ti ( and yours ) is probably around 455 rwhp divided by .85 = 535 flywheel HP ! Any way you look at it, you are puting down nearly 90-100 hp more to the ground vs stock.
(Of course , we lose about 10 hp stock or modded here in California due to our 91 octane gasoline .)
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Originally posted by ColorChange
Hey Tuner gods (Todd and Stephan), please comment on my dyno accuracy concerns. I don't want to sound like a cry baby but I really don't believe what I saw. Please comment on my questions and how LSM's car could read what they said it did.
Hey Tuner gods (Todd and Stephan), please comment on my dyno accuracy concerns. I don't want to sound like a cry baby but I really don't believe what I saw. Please comment on my questions and how LSM's car could read what they said it did.
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I believe Lou's reading were pretty close. The last level II we dynoed showed like numbers, a little more HP but the TQ was close.
Most of the GIAC programs have made great TQ. In regards to your numbers and the hook up...the dyno will read an accurate HP number without the tach reading. The TQ on the other hand could and would be skewed. So I would likely to believe the HP to be close, yet question the TQ numbers on yours since the RPM signal was in question.
When I dyno I dyno the same way every single time. We go through great lengths to ensure like situations. What is great about where we do it is all the guys know me and never ran a Porsche before I got there. So the way I taught them is the only way they know
Makes for a fun environment. They love seeing the little sixes make BIG numbers 
Most of the GIAC programs have made great TQ. In regards to your numbers and the hook up...the dyno will read an accurate HP number without the tach reading. The TQ on the other hand could and would be skewed. So I would likely to believe the HP to be close, yet question the TQ numbers on yours since the RPM signal was in question.
When I dyno I dyno the same way every single time. We go through great lengths to ensure like situations. What is great about where we do it is all the guys know me and never ran a Porsche before I got there. So the way I taught them is the only way they know
Makes for a fun environment. They love seeing the little sixes make BIG numbers
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Allboost:
375hp 302 torque stock. I have shaved heads (higher compression), triple cut valve job (better breathing), ANSA F1 exhaust (minimal restrictions)
, MSD high voltage coil and ignition, ...
Stephan:
Can you please try to answer my questions again, maybe I am an idiot. How can the same car run 250 hp and 190 torque, and then 277hp 240 torque? This just doesn't make sense, especially since the Lambo torque is almost ruler flat. If there were peaks I could maybe believe it. What gives?
375hp 302 torque stock. I have shaved heads (higher compression), triple cut valve job (better breathing), ANSA F1 exhaust (minimal restrictions)
, MSD high voltage coil and ignition, ...Stephan:
Can you please try to answer my questions again, maybe I am an idiot. How can the same car run 250 hp and 190 torque, and then 277hp 240 torque? This just doesn't make sense, especially since the Lambo torque is almost ruler flat. If there were peaks I could maybe believe it. What gives?
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It will be interesting to see what a little more favorable environment will yield. With better, less stagnent air and some proper cooling on the Mustang Dyno we should really see what is what. Looking forward to those Mustang runs! Thanks again for coming out and showing those "kids" how to disconnect a diff.
Lou
Lou
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Unfortunately I have no proof, I hate that. Since I didn't stick my head in the cockpit I would suspect as cold as she was the first time around the second run the car was much warmer. Less spitting if I recall. The TQ numbers would be different based on the RPM reading. If they corrected the RPM signal the TQ would have changed to an accurate, or maybe not reading. The dyno takes several parameters to arrive at a number. The dyno will still calculate HP even without a RPM signal. The HP increase I think could be explained by the above. The only other issue would be correction. I didn't look, was that raw or corrected?
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Thanks again Stephan, let me see if I have this. The relationship (as you well know) to torque and hp is direct!
Horsepower = (torque x rpm)/5252
So when they got bogus rpm numbers, they threw all the fudge into the torque number, right? First run probably blew a little carbon out as I haven't had my car up to 153 mph in a long time.
Horsepower = (torque x rpm)/5252
So when they got bogus rpm numbers, they threw all the fudge into the torque number, right? First run probably blew a little carbon out as I haven't had my car up to 153 mph in a long time.
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ColorChange:
Were you able to get an A/F readout from the dyno? According to somebody's description of your car on the dyno, it sounds like it may have been running extremely rich which could contribute to your low numbers.
The other thing I'd look at is the head work you had done. I've seen a lot of poor head jobs over the years and plenty of "do it yourselfers" have wound up costing themselves power by messing up the ports.
Were you able to get an A/F readout from the dyno? According to somebody's description of your car on the dyno, it sounds like it may have been running extremely rich which could contribute to your low numbers.
The other thing I'd look at is the head work you had done. I've seen a lot of poor head jobs over the years and plenty of "do it yourselfers" have wound up costing themselves power by messing up the ports.