Rando

HI
Dose anyone has a Tricom scan tool from OBD-2.com? If so, how well can it show times in-between 1k RPM intervals in a WOT run from 1k RPM to 6k RPM. I am planning to do some mods and testing on my 2002.5 and like to use it as a way to benchmark and to show where in what RPM range did the mods have to most gains. I know how fast my car can go. I what to find and improve how fast I can go fast .

Thanks

carguycw

I've used OBD-II scanners before, and IMHO the rpm vs. time sampling isn't good enough to gauge performance with. Typically the scanner will only sample at a constant time-determined rate, and the rate usually isn't fast enough to really judge performance in the lower gears.

Here's what I mean. This is probably what you want:
2000 rpm - 1.52 sec
3000 rpm - 1.83 sec
4000 rpm - 2.08 sec
[2000-4000 rpm = 0.56 sec]

Here's what the OBD-II scanner will give you:
1.40 sec - 1247 rpm
1.60 sec - 2845 rpm
1.80 sec - 4125 rpm
2.00 sec - 5499 rpm

In other words, if you're a truly dedicated Excel spreadsheet junkie, you *might* be able to extract some useful info from the scanner, but mostly what you'll see is a big mess of numbers. An OBD-II scanner is REALLY nice for diagnosing engine problems, but using it to spit out acceleration times would be like trying to measure the length of your drive to work manually with a 25-foot tape measure- it could be done, but there are MUCH easier ways.

Here's what I would recommend:
1) An NHRA-certified 1/4 mile dragstrip
2) A dyno
3) A precision accelerometer (NOT an original Gtech Pro though)
4) A buddy with a stopwatch

Rando

Thanks Chris. I will be getting one any way, but I was hoping it will be able to be used to spit out acceleration times. Dynos are great but HP and torx dose not necessary show how fast you can accelerate. A car with a higher HP to weight dose not all ways win.

carguycw

That's why my favorite way of measuring performance will always be a dragstrip.