I did put my new CS onto the corner balancing scales and performed a dyno run today Weigth: 3101lbs - full tank of 92 octane gas - no radio - no fire extinguisher - standard Alcantara interior version see attached dyno result sheets first: 5th gear; 335HP @ 8250rpm & 249.8 ft-lbs @ 4750rpm second: 4th gear; 331.2HP @ 8000rpm & 243.3 ft-lbs @ 4750rpm we did have some heat problems until we placed a fan so that it would blow through the oil cooler - otherwise the car did behave very well - with racing gas I guess that we could see 340HP (5HP was the delta I picked up last time when I used it)
If we go with 340 HP and assume an approximate 20% driveline loss - that gets to 425HP. So maybe the factory numbers are close?
Thomas - I'm taking my CS to the Dyno on Saturday - a stock 360 has previously been Dynoed on the same machine at 311.4 - see the link below. I'll report back on the numbers I see at the weekend for comparison. http://www.ktrperformance.com/services/Dyno_Graphs/Other/graph_360modena_stock.htm
Can you buy 98oct in US? 92oct on a Ferrari sounds strange to me, I gess you loose a lot of horsepower using it.
<chuckle> Definite F-Chat FAQ... a Euro vs. US confusion... we measure/report octane differently... Euro uses RON, we use (RON+MON)/2... so our "super" grade of gas is 92-94 octane... and roughly equivalent to your 98 or so.
Brian, Not sure if you saw my post on the US/Euro weight difference. While at the factory I asked what is the difference due to. The answer was US regulations require differences in 1) The exhaust system (we can see that in the photos) 2) The front and rear bumper (they have more material in the US versions) 3) The roof pillars (they have more material in them and the A pillar is thicker
The 409 to 425 static vs dynamic is also not all down to air flow but electronics, I guess detecting incraesed road speed and modifying the ECU characteristic. I didn't get a measure of how much is due to air flow and how much ECU response. Ferrari are certain the figures thay give are right and not made up in any way
Im very interested in what's going to happen here, especially robinH's input...my only question though, is that doesn't the HP peak in both cars at 8500 RPM? the torque peak is spot on ayt a claimed 4750 by the factory, but it is confusing to me about the peak power...any answers?
Thanks for the frank info. Driveline loss in a standard transmission is generally considered to be in the 12-15% range. The Z06 Corvette generally dynos at about 360 rwhp, the Viper GTS at about 400 rwhp and those cars are rated at 405, 450 hp respectively. 12% loss or less. From the dyno data it seems unavoidable that the CS makes more like 385 flywheel hp. Perhaps there is some effect of moving air over the car that should help when the car is in motion, but then again the Viper/Vette dyno stationary just fine. I doubt that anyone buys the CS or most any Ferrari for the hp alone, but someone is kidding to rate the CS at 400hp or higher. The low weight is really nice to see, though! All of my street cars are more portly than that ( the 355 might not be too bad, but I have not weighed it). I am very interested in the Noble M12; at 400 hp and 2500 lbs, it sure sounds good on paper.
Oh, I did not notice at first, but the fact that this was a Mustang dyno may affect figures a bit - I have heard that the Mustang is a bit lower than a Dynojet, and I have only used and observed the Dynojet. As for road speed and ECU, where does the ECU pick up road speed? Unless it uses the front wheels, it should detect road speed since the rear wheels are turning. Seems to me Ferrari is being optimistic about its power numbers. A better calibration is the drag strip. Don't worry about the launch, look instead at trap speeds. The Viper, an aero brick, pulls 117-119 mph typical trap speeds, the Z06 more like 113-115. Given the low weight and aero, the CS should be able to produce trap speeds of at least 114 mph. Not that anyone will defile their CS by braving the drag strip bubbas and ricers, but that would tell a more accurate tale.
Like their weight figures? Thomas' car has nothing extra... yet weighs 101# more than the owners' manual says it should... and 279# more than the marketing literature.
Yeah... what I'd love to see for all cars is 30-120mph times. Or even 30-60, 60-90, and 90-120. That's the kind of acceleration I do with my cars. And if actual driveline losses are higher in a Ferrari, then that's bad... it means lower times. In the end, HP and Torque numbers aren't too interesting... its the acceleration those get me that is.
I disagree that this represents 12% loss, it is more likely to represent 3% more power than advertized (e.g. 417 HP rather than 405 HP). However, using the more standard 15%. 335/85% = 394 HP so something is still missing.
I had it on a 4 wheel dyno - that's the reason I use a Mustang and not a Dynojet (which has a ME closer to the CS) - it did not work out since the combined roller mass (ME) was too high - i.e. we did not even get to the top speed - I can post the dyno chart once I am home - it is not pretty
the ECU interacts with the ABS/ASR system - on a two wheel dyno the ABS failure light (and corresponding error) is activated immediately - at the same time the ABS/ASR ECU generates an error which is communicated to the engine ECU via CAN bus - the error is called "road bed roughness ..." and indicates that a threshold value between front/rear wheel speed has been reached - the error is used commonly in combination with the misfire detection system however the ECU is all software so who knows whatever F (or Bosch) does with that information - this leads to my theory that P considers the dyno situation (and optimizes for it) since a large percentage of cars are dynoed while F has all kind os stupid protection mechanism in the code - theory based on having had now several P and F cars on the dyno
Sorry to pick on you e-mail but you have been the first to pop up but I am really tired of these kinds of car and HP comparisons I does not make any sense and one of these days I have to stop posting dyno charts (I know I am doing it to myself) There is no way of calculating flywheel (crank) HP from rear-wheel HP it is all guessing and very dependent on the engine / drive train, dyno, tire pressure, strap-down load, weather, .. and including operator mood F cars since the rev higher will usually have a significant higher parasitic loss than other cars 17-18% or even higher is very sensible since the loss does not grow linear with RPMs but as I said before it is all a guess and comparing it to other guesses is even worse F claims in the spec. 409HP for the CS and with 335HP we are in a sensible range I am therefore happy and looking at the curves I am even more happy since they indicate a great behavior of the engine (if you like to rev high) I dont understand the (dynamic) 425 HP claim F makes in the marketing (not spec.) literature - hopefully one of these days we find someone who can explain this at the moment I have it filed as marketing blabla (say similar to the GT3 P delivered to some magazine test in Germany that had a modified air intake system and outperformed its spec. by a margin that did not make any sense) they all do it no need to bash F I believe we will see that CSs in the US and on a Mustang dyno do come in between 330-340HP and that is a perfectly reasonable number for a 409HP claim at 8500RPM combined with the driveline layout of the 360 - this is a good baseline
Thomas, Thank you very much for doing your research and sharing it with us all!! I have to say I am a little disapointed with the 335 HP but very happy to see that the torque of 250 ft lbs is so high. It looks like the torque is about 20 lbs higher then advertised. And that's a good thing
I agree that driveline loss is at best a guesstimate and at the end of the day, what matters is acceleration. That's why I suggested a drag strip test. 17-18% seems high, even with revs, but that may be right. But having dyno'd small bore motors in Miatas to 7200 rpm, we still see 105-118 rwhp in a 1.6l engine, which works out to a guesstimated 125 hp or so flywheel, very near advertised numbers for te car and closer in rpm to Ferrari than to Viper.