| Author | Message | ||
| Rob Lay (Rob328gts)
Board Administrator Username: Rob328gts Post Number: 5762 Registered: 12-2000 |
Here are videos at Norwoods last year to give you an idea... http://www.ferrarichat.com/discus/events/dyno2002/ | ||
| Hubert Otlik (Hugh)
Intermediate Member Username: Hugh Post Number: 1161 Registered: 1-2002 |
andy: hp is a *function* of torque; it's derived from an empircally observed (measured) quantity, i.e., torque. | ||
| Andy Barre (Abarre)
New member Username: Abarre Post Number: 17 Registered: 7-2003 |
Doesn't a chassis dyno actually record HP? Since the wheels turn faster as it goes through the pull? Not sure. We used to take engines and run them on a Superflow water-brake dyno where we measured torque and graphed it against RPM's to calculate HP.... Either way, there will definitely be losses due to the drivetrain friction, etc... | ||
| Mitch Alsup (Mitch_alsup)
Member Username: Mitch_alsup Post Number: 915 Registered: 4-2002 |
What does this thing do? It measures TQ and RPM (from a spark plug wire) and computes HP. YOu get a bunch of graphs that give you bragging rights at the local pub. Why am I interested? You are a car guy are you not? Will this make my car go faster? Used correctly, it might isolate a less than perfect state of tune, and thereby allow you to do soemthing about the less than perfect state of tune. This might get some added performance. At very least, you get peace of mind. Will it hurt my car? Change the oil and avoid over redline operation, and it cannot hurt the car. Don't show up with worn out tires, either. One thing not normally done is an all gear acceleration run (1,2,3,4,5,6) The different shape of the TQ curve in the various gears can allow you to measure the rotational inertia of the drive line (not that you can do anything about it though). But it will show you that in 1st and 2nd gears a lot less than full engine power arrives at the rear wheels. | ||
| Robin Overcash (Robin)
Junior Member Username: Robin Post Number: 173 Registered: 1-2003 |
Just to be nitpicky, a brake dyno only measures torque... HP is calculated from that. It's really only useful if you're doing some tuning or mods to the car (dyno with stock exhaust, swap to Tubi, dyno again and check for improvements..) Otherwise it's just a gee-whiz thing. Definitely record it though and let us know the results! (expect about 12-15% less than the factory claims, as they generally measure HP at the crankshaft, not the wheels) -R | ||
| DES (Sickspeed)
Senior Member Username: Sickspeed Post Number: 5474 Registered: 8-2002 |
Bart - put a Tubi solo on the car, then refer to Frankie's advice of recording the notes. As we speak (ok, type), i'm listening to a 917, followed by a 333SP, P4, 312PB and so on...  | ||
| Andy Barre (Abarre)
New member Username: Abarre Post Number: 16 Registered: 7-2003 |
If it's a chassis dyno, they strap the car to the ground with its wheels on rollers. The rollers are connected to electric motors that measure the HP the car is putting out at the rear wheels. Basically, you let the clutch out and put the gas pedal to the floor. It measures rolling speed and power output right up to the redline. Mechanical risks are about the same as running at WOT on the road - except a pull takes somewhere on the order of 30 seconds (guessing - not sure exactly how long). You'll definitely want to make sure that someone points a BIG FAN at the radiators - since there is no relative wind generated by speed. Also allow for cooldowns between pulls. The shop that works on my f-car does chassis dynos for a lot of people and it's pretty interesting really. You'll know exactly how much HP your car is putting on the ROAD (figuring mechanical losses, etc...). Might also be a great time for you to try any upgrades you've been contemplating (K&N filter, etc...) where you can compare the real difference. Have fun, and please post the results! | ||
| Bart Duesler (The_bart)
Junior Member Username: The_bart Post Number: 245 Registered: 1-2003 |
Thanks | ||
| Francisco J. Quinones (Frankie)
Junior Member Username: Frankie Post Number: 201 Registered: 8-2002 |
Measures your engines performance. awesome display of power strapped on a dyno,it tells you how much horse-powa you actually have. won't make the car faster but you get the dyno printout, maybe good for bragging rights. videotape it or record the engine song for grins. if your vehicle is in good mechanical condition it shouldn't hurt it,all the manufacturers use them, although some do report rather optimistic numbers. | ||
| Martin - Cavallino Motors (Miami348ts)
Senior Member Username: Miami348ts Post Number: 5430 Registered: 5-2001 |
Bart, it will peel the leather off your dash! Just watch the dash!  | ||
| Scott Levinsohn (Rennen)
New member Username: Rennen Post Number: 5 Registered: 7-2003 |
Measures your horsepower. | ||
| Bart Duesler (The_bart)
Junior Member Username: The_bart Post Number: 243 Registered: 1-2003 |
I won a dynothingawamjig at the Ferrari get together a couple of weeks ago. This Thursday, my 550 goes on the dynometer thingy. My questions are: What does this thing do? Why am I interested? Will this make my car go faster? Will it hurt my car? I know many of you will think I am slow and you are right. (Slow in the mind but not in my car.) |