The one feature I really like is the remote start. At first I thought it would record from the instant you hit the remote start button but Andy informed me it can be set up to start at any designated RPM. We set this one to start recording at 4,000 RPM. Just hit the remote start button after the burnout and it will start recording when your engine hits the preset RPM. We set ours at 200 RPM under the starting line RPM rev-limiter.
 All it takes to arm the RPM Performance Data Logger is a pushbutton that can be reset after the burnout. After that it will automatically start recording at the RPM you program it for. |
One other feature that makes the RPM Performance Data Logger so nice is it will store up to 20 runs in case you don’t have time to download them. Once the memory is full it simply replaces the oldest run with the newest run.
The first runs we used the RPM Performance Data Logger were throttle stop runs at the IHRA Pro-Am. Of interest to us at this point was RPM while on the throttle stop, tire spin on launch or after the stop opens back up and of course converter efficiency at the finish line. WOW! From the first run on it worked perfectly. The first runs we made showed the RPM was climbing about 600 RPMs while the throttle stop was closed, not a good situation for consistency. We closed the throttle stop two additional turns and the engine stayed right on 4400 RPM
while on the stop.
The next thing we noticed was a drive shaft and engine spike on launch. This was an indication of tire spin and possible inconsistent reaction times and E.T.s. We had just raised the launch RPM from 4400 for bracket racing to 5000 for Pro-Light racing to make the car react quicker. The higher launch RPM worked as we went from no delay and .017 lights to .020 red and a need to add delay. The downside was that striking the tires that hard caused tire spin. I am pretty used to seeing dragsters launch and I could not really see the tire spin by watching but it was there and the RPM Performance Data Logger proved it. A drop of ½ pound in rear tire pressure cured that problem.
The next thing we wanted to check was to compare one run to another by using the overlay feature. You can overlay up to four runs on one graph. Do you really want to see where your E.T. is varying? This will flat out SHOW YOU! It is so easy to use that Andy actually lets me do it now. I am going to have to get one of these on “Project 4-Link” real soon.
Start line RPM is flat when on the start line rev limiter (4400 in this case). You can see the flash when the brake releases and rev limiter shuts off. Flashes about 5700 again but pulls through pretty good until the shift point (6800 rpm). The shift pulls the engine down about 1,000 rpm and if you look at the line below it you can see a little tire spin at the shift point. Right at the end of the run you can see some small spikes in the wheel speed, I think it is the bumps in the track and the tires spining a little bit. Also the finish line RPM is 6800 and tire speed is 6400. This is 400 RPM of slippage which makes it about 94% efficient (6% slippage). The flat-out E.T. on this run is 8.15 at 162.00 mph.
All in all I give the RPM Performance Data Logger an A+ on everything from ease of installation, function and tech support when you call with questions. We will continue this article next month when we get some full throttle runs in and can show you those graphs before and after some changes we make. 
Thanks to: RPM Performance Products, Inc.- 7213 NW 3rd St. – Oklahoma City, OK – 73127. (405) 495-0454 or www.rpmperf.com
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