| Author |
Message |
Erich Walz (Deleteall)
| | Posted on Tuesday, January 15, 2002 - 2:14 pm: | |
There are other home dyno options. This one uses real-time information from the engine in making its calculations. And, it gives you the numbers for the entire power curve.
http://www.charm.net/~mchaney/homedyno/homedyno.htm |
Richelson (Richelson)
| | Posted on Tuesday, January 15, 2002 - 6:01 am: | |
I think about 15-20% loss is about right. Depending on the car. Some cars from the 70's were rated high HP when in actuality are much less. |
Hubert Otlik (Hugh)
| | Posted on Monday, January 14, 2002 - 2:54 pm: | |
Your refering to the G-Tech pro's, and they are not all that accurate. For example, a friend of mine has one, and used it to time his TT RX7, he got 1/4 mile times of ~ 12.5-12.8 [this is a moddified car], later at the track, he actually got 13.0's consistently! Same elevation, same tires, same launch, and the same shift points!
So, if anything, the G-Tech's crude measurments are good for the ego! |
Michael (Mtabije)
| | Posted on Monday, January 14, 2002 - 2:31 pm: | |
Are those G-Force or what every you call them...accelerometers that look like radar detectors that you mount on your window, do they work?
I wonder if there has been a shop dyno comparison with this doo-hickey G-Force machine, and if the results were similar. I'll have to research that. |
Eric Hawley (Eric)
| | Posted on Monday, January 14, 2002 - 12:09 pm: | |
Last spring, several members of the NW region Ferrari Club visited a local Dyno shop, and my 95 456 showed a corrected 371 HP at the rear wheels. With Ferrari literature claiming 436 HP, this works out at pretty close to 15% drivetrain loss. |
J. Grande (Jay)
| | Posted on Monday, January 14, 2002 - 11:57 am: | |
When I had my N* Fiero it put out 300hp (claimed by GM) and on the dyno it showed almost 260hp at the wheels. 30% loss sounds like alot even for an automatic (which the mondial is not). I'll have to get the 308 GT4 on a dyno when it's done, I'm also interested in knowing hp to the wheels. |
Dave Mills (360dave)
| | Posted on Monday, January 14, 2002 - 11:08 am: | |
Few people have actually dynoed their engine on a stand as well as in the car on a chassis dyno. So real numbers are typically pretty hard to find. But 33% drivetrain loss sounds like quite a stretch to me as well.
Another option is to get the car on a 1/4-mile track, and use some of the horsepower calculators to estimate the power. I may have to do that with the 360. I was told by the salesman that strapping the car down by anything other than the wheels will quite possibly bend suspension components (anyone have experience with this?). A dyno shop is probably not going to be able to strap the car down right, I'd think. But I would like to know what kind of power it gets to the rear wheels.
Dave |
Paul Newman (Newman)
| | Posted on Monday, January 14, 2002 - 10:14 am: | |
No offense, but 33% loss is high. Any dyno testing Ive been involved in uses 15-20% as a rule of thumb. 20% applying to automatics. Maybe the 270hp rating is generous. Ferrari has been known to inflate their numbers. I have not dynoed my 308 GTB yet. Using a late model Z28 as an example, RWHP measured at 224 on a chassis dyno worked out to approximately the 275 flywheel HP that GM claimed the engine produced.
Paul. |
Peter Connolly (Mondial_32_Aus)
| | Posted on Monday, January 14, 2002 - 8:41 am: | |
87 Aust Mondial 3.2 Dynoed at 135kw (~180HP) at the rear wheels, flywheel power is quoted as being 200Kw (270HP). This 33% loss thru the drivetrain should be about right.
Remember that very few dyno's are the same, they are setup differently and you will get wildly varying results from dyno to dyno. They are generally used to assess the benefit of fitting a mod or for progressive tuning.
I am a veteren of dyno's as I have had 3 Subaru WRX's and have had my cars on the dyno extensively when fitting mods and tuning the aftermarket ECU's. The amount of debate in the WRX clubs over different dyno results is enormous!
PC |
Michael (Mtabije)
| | Posted on Monday, January 14, 2002 - 1:45 am: | |
Any of you ever dyno your cars?
What were the operating conditions when these were done?
Results?
Does the generalized 15% loss from engine hp to wheel hp apply to Ferrari's?
Any good articles on this?
Thanks in advance for your comments |
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