I read that the resistance in ohms + 1000 is the RPM value, I just wanted someone to verify this.

I have two potentiometers mounted in my N20 switch panel so I can fine tune my RPM switch from inside the car. It should be pretty sweet but I need to get a better ohm meter and I don't have any of the pills to test.

Thanks
Dustin

 

I got
5100=3.70 kohm
5300=3.89 kohm
5500=4.08 kohm

 

Thanks a lot for the quick reply! From the numbers you got it looks like the resistance in ohms + 1400 gives you the RPM.
I got the idea from corral.net where there is instructions to build the "ARM" switch. It said that the resistance in ohms + 1000 would be the RPM but it sounds like that was bad information. Has anyone else made an adjustable module for their RPM switch? Do these numbers sound good?

Right now, to set the "on" RPM I just revved my car to 3000 RPM'
s and then slowly turned the pot until my light came on. I don't want to try this at 5800-6000 RPM's for the off value.
This will turn out to be better and cheaper than buying the modules if I can make it work.

Thanks a lot
Dustin

 

TTT

 

There used to be a table of all the values somewhere on the internet. Maybe someone has it or a link to it? I'll host it if someone can email it to me.

 

That would be great

 

...I'd be willing to measure all the pills I have, if we need to recreate the info... I have 8-9 different ones.

Dave

 

http://www.corral.net/tech/powerplant/arm/

 

I have the adjustable module from 4600-6800 I think I can make sure those values are good, except I don't have the best multimeter.

 

That link is where I got the idea. The numbers on there aren't working out for me though. When I set the "off" value at 4800 ohms (supposedly 5800 rpm) my light (the light is on when the system is spraying) doesn't go out before the transmition shifts. My A4 should shift after 5800 rpms right? The tach says it shifts at about 6000 but I don't know if I should trust it.

The numbers that someone measured earlier look like the formula should read: Desired RPM = Resistance in Ohms + 1400.

Thanks for the help, hopefully I can get this figured out.

 

I know for a fact there was an old chart that had exact values for each rpm and suggested using high precision resistors and showed you how to pull the resistor out of the pill msd gives you and replace it with whatever you want..

 

I remember that chart too. I can't find it right now, but I'll keep looking. I even printed it off and put it somewhere for future reference......Now if I could only find it again!


How about that, just found my printed version but the website I got it from is down. I do have an email address for the guy who had it before. blownf1@aol.com if it still works. Otherwise here is what that list says:

5100 rpm - 3691 ohms
5200 - 3791
5300 - 3877
5400 - 3979
5500 - 4082

 

Thanks for all of the help guys. Does the chart you have list values any higher: 5700, 5800, or 5900 rpms is where I would like to set it. Those numbers again look like the ohms + ~1400 gives you the rpm. I will try it out again setting the "off" pot at ~4300 ohms giving me approximately 5700 rpms. I'll tell you how it works out.

thanks again
Dustin

 

Did anyone ever check out Harlan's Window switch.
It does pretty much what your saying.

Here's the link.
http://www.harlan-engineering.com/store/store.html

If you already have the window switch then making one would be cheaper but if you don't have one then this may be the way to go.