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Anyone has a DYNO GRAPH for a 360 (6-Spped or F1)?

Discussion in '360/430' started by Jimmy540i, Feb 25, 2004.

  1. Jimmy540i

    Jimmy540i Formula 3
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    I'm waiting to Dyno my 360 in March. At this time, I'm eager to know if anyone of you have a Dyno Chart of any 360 (6-Speed or F1), I would like to know the RWHP of any 360.

    THANK YOU!!!

    Regards,
    JIMMY
    www.Jimmy540i.com
     
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  3. 4sfed4

    4sfed4 Karting

    Dec 22, 2003
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  4. Jimmy540i

    Jimmy540i Formula 3
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    Thanks, I actually saw this page a while back.

    311 RWHP is just WAYYYYYYYYYYYYY under what Ferrari stated. See if we use a 15% power-loss method, it's more like 365 HP at the Crank, it's 30HP under what Ferrari says.

    Thoughts?


    Anyone has any more Dyno Chart for any 360?
     
  5. 4sfed4

    4sfed4 Karting

    Dec 22, 2003
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    My thoughts are that there seems to be a pattern here :D
     
  6. 4sfed4

    4sfed4 Karting

    Dec 22, 2003
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    I know isnt what you asked for, but heres an F355 which are rated 375 hp I believe? Again, a rather strange and excessive driveline loss seems to be present.
     
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  8. Jimmy540i

    Jimmy540i Formula 3
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    wow.... the HP seems to be very low on the 355
     
  9. Jimmy540i

    Jimmy540i Formula 3
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    Any 360 owners on this board actually dynoed thier 360???

    Thank you!
     
  10. thomas_b

    thomas_b Formula Junior

    Sep 15, 2003
    765
    360 Modena's dyno between 310 and 320 rwhp - 311rwhp is one example at the lower end - Willis360 with 323.8 rwhp is an example for one at the upper end

    inertia losses in the gearbox and transmission are higher for 360 than for example for P cars because:
    - the 360 rev's higher
    - the drivetrain is more complex because of the gearbox layout

    you have to expect 18% - 20% for a 360 - e.g. taking 395HP of the Modena you get 18% for Willi's car and

    note that tire pressure and even how hard the car is strapped down will influence the result

    also keep in mind that dynos suffer from that fact that they can not simulate the mass of the car, road and air flow resistance - the car therefore will accelerate faster which results in more inertia losses - mass equivalent for Mustang dyno's is 1088kg and for Dynojet's is 1633kg - i.e. HP will come out higher on a Dynojet
     
  11. Jimmy540i

    Jimmy540i Formula 3
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    To match the 400HP (395HP) which Ferrari claimed, a 6-speed 360 should achieve at least 340 RWHP on Dyno (using 15% power-loss on Manual transmission). And, n F1 should be near 320 RWHP (using 20% power-loss on Automatic Transmission)

    Does this mean Ferrari overstated the 360 engine?
     
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  13. t88power

    t88power Formula 3

    Feb 19, 2001
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    Both Manual and F1 360 use the same tranny, no 360M uses an Automatic tranny.

    Thomas_b said it very nicely.

    Ernesto
     
  14. stephens

    stephens F1 Rookie
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    Feb 13, 2004
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    From my limited experience, Dynojet dyno's are calibrated for 18% power loss on a manual and 21% on an auto. The real losses are irrelevant, it is what the software writer for the dyno thought it should be when he wrote the code for the dyno, so there is no point going into a theoretical argument about real losses. In Australia the local dyno brand here is Dyno Dynamics, they work on a 28% power loss. What this means is that a Dyno Dynamics will generally give around 10% lower HP readings than the Dynojet.
     
  15. Mako99

    Mako99 Formula Junior
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    Dec 29, 2003
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    Yes, and they always have.

    Why is this shocking to the board? Ferrari has always overstated power output, hell all the way back to the 70s.

    I've seen 355s with nothing wrong on them dyno out at 265HP - 275HP consistently. Three in a row actually, leaving their owners scratching their heads.

    I read recently that car companies usually use a rule of five engines to determine their HP ratings, for example Honda uses the following rule:

    Out of five random engines that roll off the line, two will be more powerful than their published figure, two will be less powerful than their published figure, and one will be spot on. So basically three out of five of the engines are achieveing or beating the published figure. Honda's tolerances are rediculously tight, so it's not like the total spread goes beyond 5% either way.

    God knows how Ferrari comes to their published figures, but as we've seen with the Stradale dynos, nothing has changed. They're still pretty optimistic when it comes to power output and the curb weight of their cars as they've always been.

    Instead the actual performance times are all that matter when judging an F-car, meaning its 1/4 mile time, 0-150MPH time, top speed, etc.

    I wonder if the Ferrari supercars are any different, has anyone ever seen an F50 or Enzo plot? Be interesting to see if the attention paid to those car's powerplants results in more consistent outputs.
     
  16. Aircon

    Aircon Eight Time F1 World Champ

    Jun 23, 2003
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    At the risk of repeating myself, I've seen the following Ferraris dynoed with almost exactly the handbook stated horsepower being accomplished:-

    308GTB F/glass
    365BB (using the SAE/DIN from another thread)
    512BB
    330GT
    F40

    The 355s readings didn't stack up, but their straight line performance seems to stack up with what Ferrari claims...I don't get that one at all.

    However, I don't know how you can say Ferrari has always overstated their HP figures based on seeing a few 355s on the dyno.

    Also, every Ferrari I've weighed has come in almost exactly at the published handbook weight with a full tank of fuel, where the only porsche I've checked came in 100kg MORE.
     
  17. Mitch Alsup

    Mitch Alsup F1 Veteran

    Nov 4, 2003
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    Ok, lets talk about this:

    The 15% loss from flywheel to contact patch is (basically) accurate for a drive line
    that goes through a transmission with 6 bearings and has a 1:1 direct drive without any gear teeth (shaft locked to shaft) absorbing/transmitting power, followed by 2 or more universal joints followed by a differential mounted in a solid rear axle. This is characteristic of a Mustang or Camaro drive line, and as such is fairly accurate. This is the drive line for which the dyno is calibrated.

    By the time you add an independently suspended rear end, the drive line losses are nearer 16%-17% than 15%, Vette and Viper drivelines are representative here. There are more parts, more bearings, bushings, and more degrees of freedom; therefore, more power is absorbed in transmitting the driveline forces from the engine to the contact patch.

    Last time I looked in a Ferrari F355 Gear box I counted 16 bearings, and 4 sets of gear teeth interacting to transmit power from the clutch shaft to the drive axles. This arrangement simply has to absorb more power than does the more direct arrangements found in american cars. The fact that Ferrari can keep the losses below 20% with so many things happening in the gearbox are a mark of good engineering. A loss of 18%-19% should be expected from such an arrangement.

    The dyno has to make assumptions about the rotational inertia of the driveline inorder to compute rolling wheel acceleration torque and from that compute HP and TQ. Its not just the rotating inertia of the rolling wheel that gets accelerated, the wheels, tires, brake rotors, axles, transmissions gears, clutch and crankshaft are also part of the rotating inertia, and its the rotating inertia that the dyno measures. Making the rolling wheel have 4000 pound-feet of rotating inertia relegates the rest of the drive line inertia down in the 5% of the rolling wheel inertia. The dynos I know of have been programmed for the drive line inertias of a Musttang--Vette. These cars have a 360 degree V8 crankshaft with lots of counterweighting, a rather heavy transmission operating at crankshaft speeds, a heavy drive shaft from the engine to the differential, and rather heavy axles.

    The F355, on the other hand, has a 180 degree crankshaft with minimal counterweights, runs the transmission at slow shaft speeds as if they were after the differential (crown gear), has no dirve shaft, and smallish axles. Hardly a comparable driveline!

    This makes the rotational inertia assumptions in the dyno computer inaccurate when dynoing a Ferrari, or other race car engine driveline combination. These assumptions can be changed, but to what? The only real way to do this right is to measure the engine on an engine dyno, and then in the car, and adjust the shape and magnitude of the chassis dyno output to look like the shape magnitude of the engine dyno output. And then the chassis dyno is only accurate when measuring that car!

    The dyno also has to make assumptions about barometric pressure, humidity, temperature, and attempt to compensate by means of thermodynamic conversion equations back to a standard temperature (59 dF), pressure (29.x inches of mercury) and relative humidity (60%?). As such they provide a common grounds to compare different cars measured on different dynos on different days....However, the error inherent in any one measurement after correction is on the order of 3%.

    Take a batch of parts that can be used to assemble 100 engines, and assemble 100 engines with dilligence and care. The spread of optput power across this set of engines will be on the order of 5%, with 63% within 2.5% fo the average output power. So, most engines will be within 10 HP of the factory quoted output, however a few weaklings and a few killers will also be found.

    Under the things addressed in this diatribe, an F360 engine should dyno around 320 HP or above on a chassis dyno calibrated for american automobiles and corrected to standard temp, pressure, and humidity. Any engine that dynos within that range is actually a 395 HP plus or minus the production window of the Ferrari factory (about 20 HP or +/- 10HP) engine measured on a constant RPM engine dyno. A F355 engine should be about 300 HP to meet its 375 HP factory stated crankshaft ouptut power. The 96-99 F355 engines tend to be a little soft in the power department compared to the 95 F355 engines. More restrictive intake manifolding, different exhaust headers and plumbing, and a more emissions friendly OBDIO-II ECU contribute to this softness.

    In addition, if you make a couple of hundred pulls on an engine in either a engine dyno or on a chassis dyno, the engine output will be seen to vary 3% or so with 63% in the 1.5% range or slightly better. So the engine output actually chages over time, at the same RPMs, at the same barometric pressure, at the same relative humidity, same gas,... Is it any wonder that we can't compare outputs any closer than we do?

    There is noise in the measurement system, part of the noise is in the engine output itself, the rest in the measurement system. There is no way to get rid of this noise, except by taking so many measurements that the actual underlying physics, chemistry, and mechanics are visible in the data. Few people have the depth of wallet to perform these kinds of study.

    Finally, using different gasoline (european) and doing their testing in Italy and being a factory ferrari might overstate the power output as seen over hear (ROM+MON/2), heat, humidity. Using different dynos (engine vs. chassis) calibrated for different driveline configurations, calibration error:: its a wonder we can do comparative dynoing at all......
     
  18. SteveB

    SteveB Karting

    Oct 5, 2003
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    It is interesting reading what everyone has to say about rwhp vs. flywheel horsepower. Since I have a DynoJet I can tell you that making any kind of general assumption about drivetrain loss is just a guessing game.

    For example, my engine on an engine dyno made 838 hp. The motor was installed in the car and the next day with virtually identical conditions it made 707 rwhp on my DynoJet. That amounts to a 15.6% drivetrain loss. Keep in mind that this car has an independently suspended rear end.

    DynoJet doesn't like talking about converting between horsepower measured on their chassis dyno to horsepower measured on an engine dyno. There are simply too many variables. What DynoJet - or any other chassis dyno - wants you to do is use their dyno as a measurement tool to determine whether improvements have been made or not.

    I see more and more people, magazines, shops, etc. starting to refer to rear wheel horsepower when quoting numbers and improvements rather than engine dyno numbers. I think this is due to the number of DynoJets that are now out there.

    As far as trying to make numbers repeat from day to day, this can be a little difficult unless conditions are very similar. Under similar conditions I can make runs from week to week with very little variance. The one thing I am not crazy about is the SAE correction formula that is used. In my area of the country - Washington state - I am routinely penalized because of our cold weather. My 714 rwhp run is actually 722 rwhp uncorrected. In other words, the car actually made 722 rwhp but because of the lower temperature, the SAE correction formula downgraded me to 714 rwhp.

    Steve
     
  19. davequick

    davequick Formula Junior

    May 27, 2003
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    Again, not what was asked for, but here's my 328... tested at 213 w/tubi and no cats. Next weekend I'll have a chart with stock exhaust and cats from the same car.

    There will be at least 4 other ferraris at our local Dyno Day event up here in the northwest and I'll ask to photograph each of the other owner's results - especially if there is a 360 there - specifically for this thread.

    -dq

    p.s. as if you couldn't tell from the avatar... it's for sale: http://ferrari.threefourfive.com :)
     
  20. bripab007

    bripab007 Rookie

    Feb 22, 2004
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    The fact that a 360 has no 1:1 gear ratio in any of its 6 gears wouldn't have anything to do with the lower-than-expected wheel horsepower numbers would it? Perhaps the runs were done in 6th gear and threw off the dyno calculations?
     
  21. 4sfed4

    4sfed4 Karting

    Dec 22, 2003
    231
    I like the way you talk!

    That means my 2.2L Dodge is making something around 520 crank hp! I like how it sounds, but I am not sure if I believe it!
     
  22. TimF40

    TimF40 Formula 3

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    I'm getting my 2004 360 dyno'ed this Saturday. I think Thomas is right, I'm expecting somewhere between 310-320 rwhp (based on other posts). Given that the car only has 1000 miles on it (barely broken in), and I'm using only run-of-the-mill premium gas, I expect to land in the lower range... I'll let you know the results - Tim
     
  23. Brian C. Stradale

    Brian C. Stradale F1 Rookie
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    Interesting analysis, guys... but interpretation depends a lot upon the question...

    If the question is: Is Ferrari lying abou their engine HP? Then your analysis likely explains how we may be getting exactly the engine horsepower Ferrari said we should, even though we are getting lower rear wheel horsepower than we initially thought. Ferrari drivetrain losses are higher than the rule of thumb.

    However, if the question is: Does my 400HP Ferrari have as much power as my buddy's 400HP Corvette? Well, then the answer is, the engine has the same horsepower, but the car does NOT.

    In the end, we are after rear wheel horsepower. We love the sound of our high-revving engines... and we love the horsepower we get from the lighter engine due to those high revs... but, what we are saying in this thread is that although higher revs raise engine horsepower per liter, they also increase drivetrain losses. Thus, we don't really get as much additional horsepower from those high revs as we might have thought.

    For car-comparison purposes, we should subtract 5% from our high-revving cars' HP numbers before comparing with their American competitors. Right?

    Interesting. And then Mitch continues...


    Again, while this is a valid point when trying to determine if Ferrari is mis-stating their engine horsepower numbers, its not something you want to "adjust away" when analyzing car horsepower. We want cars that have as low as possible rotating inertia... we want cars with minimal drivetrain losses... we want to get as much horsepower as possible to the ground.

    So, the argument that "Ferraris engine horsepower numbers are correct; but you're seeing less on the dyno because Ferrari's drivetrains have far more lossage and far more rotational inertia, reducing rear wheel horsepower" is NOT exactly encouraging.

    But my biggest question on this latter note is this: you seem to be implying that to compute rear wheel horsepower the dyno has to adjust not just for they dyno's rotational inertia, but also for the car's rotational inertia. Here, I disagree. For rear wheel horsepower, I want to know the torque/horsepower that is available to accelerate the car forward. I want the torque/horsepower that must be spent accelerating the rotating parts of the car to be deducted.

    Sooooo, if I decide to stop using or worrying about engine horsepower and just focus on rear wheel horsepower numbers, then shouldn't I be trying to "turn off" any dyno adjustments for rotational inertia of the car's rotating parts??


    And finally, I think the ultimate question is this one:

    It makes me wonder this... is the G-Tech or other accelerometer based tools in a moving car not actually a MUCH better way to dyno a car than the dynos??

    Yes, you need to take care to find a flat, level road... but as long as you're close, that adjustment seems no more erroneous than dealing with the rotational parts of the dyno, the lack of proper airflow in the dyno, the heat build-up in the dyno, engine management software doing funny things based on lack of undriven wheel speed or airflow, and on and on.


    Just food for thought.
     
  24. G-force

    G-force F1 Rookie

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    Some of the analysis here are quite interesting and to some degree
    correct but.....Bottom line is ....310-320 RWHP is no matter how you slice it is terrible by performance standards in my opinion.
     
  25. 4sfed4

    4sfed4 Karting

    Dec 22, 2003
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    Many Hondas rev high and they dont seem to show excessively drivetrain losses in order to get back to the "rated" power. A stock S2000 for instance, revs to nearly 9000 and makes 205 whp or so. Its rated at 240. Thats a 15% loss.

    On the same dyno, an F355 laid down 298 whp with a 375 hp crank rating.

    Again on that same dyno, a 405 crank hp rated ZO6, made 370 whp.
     
  26. Mitch Alsup

    Mitch Alsup F1 Veteran

    Nov 4, 2003
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    Yes, the honda has a driveline akin to a Vette. One gear in the tranny is a direct drive (input shaft to output shaft) that does not use a gear to gear interface to transmit the forces. A dog on the input shaft latches a face on the output shaft. The differential has a single gear (90 degree turn). For a total of 1 gear of loss and various bearings and bushings and CV joints.

    The F355 has a minimum of 4 gear teeth meshing to tansmit power; drop gear (crown), spur gear (90 degrees), transmission gear (ratio gear) and the up gear (output shaft to differential); along with the various bearings, bushings and CV joints.

    The Z06 is underrated by Chevy.

    Front engine cars with wet sumps are perfect for a transmission architecture where the intermediate shaft is below both the input shaft and the output shaft. Since the crankshaft centerline is so hig, there is plenty or room to put half or the gears under the crankshaft. Anyway, these transmissions get a 1:1 gear ratio by directly coupling the input shaft to the output shaft on the same centerline and avoid any gear teeth losses in the 1:1 gear.

    The F355 transmission, on the other hand, is A) rotated 90 degrees WRT the engine (transverse), B) rotated such that the input and output shafts are at the same height above the road surface, C) operate at slower-than crankshaft rotational speeds (30%). This puts all the heavy parts lower than the crankshaft centerline even after installing a dry sump that lowers the engine by some 4"--helping the CoG.
     
  27. Brian C. Stradale

    Brian C. Stradale F1 Rookie
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    Mar 17, 2002
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    So, you are saying that Ferrari chooses to lose 3-5% of its horsepower in the driveline in order to lower the engine center-of-gravity 4"?

    Interesting trade-off.
     
  28. thomas_b

    thomas_b Formula Junior

    Sep 15, 2003
    765
    Mitch, I am confused - to busy to think it through but I thought the F355 and 360 had similar layouts - what to you mean by A,B,C - see picture of 360 gearbox
     

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