Dyno tutorial
Posted: Mon Apr 18, 2005 3:37 pm
Specifically for Camry or Solara owners with the V6 1MZ-FE and the A541E 4-Speed automatic transmission but the concept also applies to other automatics with a little modification:
There are many dyno operators that don't do well with automatics. Don't let them do 2nd gear pulls. Your numbers will be roughly 8% low, the run duration is too short to get all the data and it is just an easy way out for them. The reason they like to do 2nd gear pulls is, they can lock it into gear and not worry if the converter is going to lock-up or not. Also, they have trouble with the tranny downshifting when in 3rd. Don't let them take the easy way out, it's your money, get what you came for. This is what you need to tell them to allow them to successfully make a 3rd gear pull with the automatic.
Take off the overdrive (disable it with the button) and put the car in drive (or the operator can walk it through 1rst + 2nd, doesn't matter). In 3rd gear make a smooth increase to around 73MPH, start the dyno right there or just before. At 73MPH, don't just floor it, walk into it, smoothly taking it to the floor and hold it for the run. I've had it downshift into 2nd gear just below 78MPH. This procedure will keep it from downshifting.
Like I said, this is applicable for other automatics as well, the speed will probably differ though. A good way to figure it out before going to the dyno is to (not on a public road of course) floor it and see what MPH your car wants to shift from 2nd to 3rd. Subtract just a little bit off that number and that's where you want to start. -JoeB
There are many dyno operators that don't do well with automatics. Don't let them do 2nd gear pulls. Your numbers will be roughly 8% low, the run duration is too short to get all the data and it is just an easy way out for them. The reason they like to do 2nd gear pulls is, they can lock it into gear and not worry if the converter is going to lock-up or not. Also, they have trouble with the tranny downshifting when in 3rd. Don't let them take the easy way out, it's your money, get what you came for. This is what you need to tell them to allow them to successfully make a 3rd gear pull with the automatic.
Take off the overdrive (disable it with the button) and put the car in drive (or the operator can walk it through 1rst + 2nd, doesn't matter). In 3rd gear make a smooth increase to around 73MPH, start the dyno right there or just before. At 73MPH, don't just floor it, walk into it, smoothly taking it to the floor and hold it for the run. I've had it downshift into 2nd gear just below 78MPH. This procedure will keep it from downshifting.
Like I said, this is applicable for other automatics as well, the speed will probably differ though. A good way to figure it out before going to the dyno is to (not on a public road of course) floor it and see what MPH your car wants to shift from 2nd to 3rd. Subtract just a little bit off that number and that's where you want to start. -JoeB