I have a van and I will be installing a tachometer today so I can finally see how fast the motor is going!:)

Anyway, the directions say to cruise at highway speeds and calibrate the tachometer that way. I just need someone to tell me a certain speed/rpm combination like 65 mph is xxx rpm or something like that.

I have the 4 speed automatic tranny and 3.73 gears. It came with and has 245 tires. No changes in tires or gears or anything.

Thanks for any info.

the measured mile, several averages, and a stopwatch would probably be better

I believe that at 70mph you should see ~2100 RPM with that combination with the tranny in OD and TC locked.

2050 @ 65, that is, if that's not breaking any laws.

Second method: use high idle switching with the ECM so you can set it while parked. Check out Kennedy's site for more info on "how-to" with fast idle setup. I dailed mine in while in the driveway. Mine was reading 2050 @ 65 w/4.10. Now, I'm a little disappointed, yet more smypathic to that fuel needle getting more friendly with "E", than with previous calibration. Now reading 2250 @ 65, almost 10% off. Close 'nuff for nuclear warfare.

Hook a scanner up to it, in data display, Engine RPM will be right at the top.

Hook a scanner up to it, in data display, Engine RPM will be right at the top.
you cheater! Not ALL of us have the fun toys.:p:

Thanks for the replies. I guess after I set it at a higher rpm, I can double check it by seeing what it says for idle speed when I go to park it.

What should the idle speed be? I think I've read 700 somewhere?

I think I'll look into getting a scanner. Any suggestions? I know there's probably a lot of information available here with a search!

For a scanner a GM Tech 2 is about your best bet. But be prepared to lay down some $ for one. Check out ebay, they're on there all the time, I'm going to 5 finger one for myself ;)