There is NOTHING wrong with a Mustang dyno, other than the fact that most people like to compare Dynojet numbers. The Mustang usually reads lower.

The higher torque value shown was ACTUAL torque at the wheels.

See there's this thing called a transmission that acts as a TORQUE multiplier. When you put engine torque through this thing called a transmission, the torque at the wheels varies according to GEARING. There's no way a 3500lb car could move forward with only 350rwtq. That's why we have transmissions to vary the torque load.

In BigBake's case, the dyno operator did not know how to utilize the software to display simulated engine torque, accounting for drivetrain loss. The dyno operator running the dyno during the dyno day mentioned on this thread will be able to display engine torque.

For those that do not understand dynometers and would like to learn:

The Dynojet 248C uses a BIG rolling drum. The car is placed on the drum, the wheels spin it, and the rate at which the wheels acclerate the drum is measured. Since the drum is of a known weight, HORSEPOWER can be calculated. Horsepower is the ability to do work OVER TIME.

The Mustangdyne dynometer is an eddy brake dyno. It uses hydraulic fluid to make a known resistance to the rollerS. (Yes, the Mustang has 2 rollers) Once the wheels are able to overcome this resistance, the dyno adds more resistance. This known quantity of resistance is called TORQUE. Since this actual torque is much higher than what the engine is producing due to that transmission thingy, it gets confusing to some people. A competent dyno operator will be able to display engine torque instead.

If you are able to measure horsepower OR torque, the other can be found at any given rpm point by the following calculation:

HP = (TQ x RPM) / 5252

FWIW, I actually use this dyno to tune cars, because of its ability to vary load. The dynojet has a program called "dynatrac" that uses the drum brake to simulate load, but it does not quite do the job for me. This particular dyno has shown a 16% difference from the dynojet 248C in my own testing. (Every time I finish tuning a car on this dyno, I travel to a shop with a dynojet 248C to get comparable numbers for the masses) The last car I dynoed on this dyno put down 379rwhp, 448 SAE on the dynojet, and 452 STD on the dynojet.

Have fun at the meet, and tell them Bryan "no shoes" said hello.

I'd come out there, but I am flying down to South Carolina to pick up a customer car to tune next week.

 

I've read so many things this morning, I don't know any more. Do they need to input a weight for the vehicle on a Mustang dyno?

 

The Mustang dyno requires the weight of your vehicle ONLY for the 1/4 mile simulation and for load based tuning (ie: driving up a 30% grade).

 

Is the dyno day still going to happen I'm hearing it may not because of the event at VMP but us domestics will still come out and try it and I'm sure some imports will still be in town

 

yes as far as i know everything is still on for this saturday

 

bump

 

Well the dyno day was cancelled because of rain.
I think they are going to have it Next saturday though...
Oct 18th.
Think same time.

 

sounds good to me allows more time for me to tune on the streets before I get on the dyno

 

well the mustand dyno i was told that is can put more stress on your car.. instead...

 

http://www.mustangdyne.com/Articles/...article-01.htm

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