ATTN: Anyone with MSD-type RPM Modules

[Italian LX]

I've looked all over on the web and can't seem to find a cross-reference for the resistance value of each RPM module.

I have the 3000 series and a couple of the 6000 series and was able to measure the resistance with an ohm meter, but I need to know all the other series resistances.

What I have found is that it seems like the values are linear within a particular series (ie. the 3000 sries are all seperated by 160ohms); however, it doesn't appear that they are linear across the entire range. The modules I have go from 1890ohms (3000rpm) to 2530ohms (3800rpm), but the 6000rpm module measures 4570ohms which doesn't graph out linearly.

The bottom line is, if you have any RPM modules and access to an ohm meter, I would realy appreciate feedback as to what the resistance value is for each of the ones you have.

Thanks.

[96GTS]

Just buy the pill packs cheap ass :shake:

[QWKSNKE]

:lol:

[QWKSNKE]

Brian. I still have that pack for the 6AL at the house

[Italian LX]

Just buy the pill packs cheap ass :shake:
That's my problem.... I don't want to have to worry about a bunch of pills at the track and I'd rather not spend $150 on an adjustable 3-step that I could easily make my own. :P

[Wickd GT]

That's my problem.... I don't want to have to worry about a bunch of pills at the track and I'd rather not spend $150 on an adjustable 3-step that I could easily make my own. :P


Damn Brian, get the didgital box I have 4 adjustable, the only thing you do is move it to the degrees you want it to retard, don have to worry about chips at all. Remember this, you do it yourself, it might work fine, but when you don't expect it, the damn thing does not work and you have melt down half the track, hum.... Stop been so cheap, BITCH!!!



;) Edgar

[Italian LX]

Remember this, you do it yourself, it might work fine, but when you don't expect it, the damn thing does not work and you have melt down half the track, hum.... Stop been so cheap, BITCH!!!
I will still be using the pills for my over-rev and burnout limiter, but I want an adjustable for my launch limiter (just like an MSD 8735). The only thing a 3-step box does is selects which of three resistor values goes to the MSD rev limiter depending on two inputs. There's nothing there that would cause melt down at half track. :P

. . . well, no more than anything else I have done on my car. :D

[ChipR4cam]

:lol: at all of y'all.

[Italian LX]

So, no one has access to any RPM modules and an ohm meter? :shrug:


Lee was able to hook me up with the 6000 series; I'd like to get the info on the 4000 and 5000 series. Even if you only have 1 or 2 from that range it would help.

[slvrbullit]

I have some but they are the 6000 series.

[coupe]

I wouldn't own any MSD stuff. Too many "I had to send it back in" stories for me.
Sorry Italian. :( Good idea though on the "adjustable" one.
Or you could just buy an Accell 300+; it already has the adjustable rev-limit toggle built in. :D I've had great luck outta that product.

[96GTS]

I wouldn't own any MSD stuff. Too many "I had to send it back in" stories for me.
Sorry Italian. :( Good idea though on the "adjustable" one.
Or you could just buy an Accell 300+; it already has the adjustable rev-limit toggle built in. :D I've had great luck outta that product.
He's too cheap:rolleyes:







:jester:

[Italian LX]

He's too cheap:rolleyes:
:yup:

[Italian LX]

Well, I finished the 3-step yesterday and tested it out at the track today. It worked great and makes it a whole lot easier to leave the line at a preset RPM. :nice:

. . . plus it sounds cool off the line too. :burnout:

[Dale McPeters]

:pics:
:slips:

[QWKSNKE]

I wouldn't own any MSD stuff. Too many "I had to send it back in" stories for me.
.


Really? My 6A box has around 60k miles on it. Never had a problem with it.

[Italian LX]

:pics:
I'll try to throw together a tech post on the wiring. It's really simple and cost less than $20. Sure beat paying MSD $150 for the same thing. ;)

:slips:
I got a 1.693 sixty-foot time with it. :burnout:

[Dale McPeters]

I'll try to throw together a tech post on the wiring. It's really simple and cost less than $20. Sure beat paying MSD $150 for the same thing. ;)

That is what I need as I am also cheap!!
I do have the 6AL box but need something else on the other car...


I got a 1.693 sixty-foot time with it. :burnout:

That is a good sixty foot time. Better than my 2.0 stuff....:lol:

[coupe]

Brian...
the New "DSP adjustable 3-step Rev Control" :shrug:

[Italian LX]

That is what I need as I am also cheap!!
I do have the 6AL box but need something else on the other car...

Well, you still need the 6AL box. The 2-step and 3-step modules that you buy fom MSD just interface with your existing rev limiter. The only thing they do is select which RPM chip that is used depending on whether your clutch/transbrake or line-lock is in use. Basically, I just have a relay for each that activates the different RPM values.

However, I also had to add an additional relay to latch the staging RPM so that it would only operate during launching and not during any additional shifts. Otherwise, the car tends to backfire between shifts in a 5-speed car. :bomb:

[Dale McPeters]

Well, you still need the 6AL box. The 2-step and 3-step modules that you buy fom MSD just interface with your existing rev limiter. The only thing they do is select which RPM chip that is used depending on whether your clutch/transbrake or line-lock is in use. Basically, I just have a relay for each that activates the different RPM values.

However, I also had to add an additional relay to latch the staging RPM so that it would only operate during launching and not during any additional shifts. Otherwise, the car tends to backfire between shifts in a 5-speed car. :bomb:

Well I guess I will have to dig the other MSD box out of the building. ;)
Now do a write up on the particulars...... :jester:

[93Cobra#2771]

http://www.corral.net/Tech/Engine/arm/arm

Just happened to see this today...

[93Cobra#2771]

Don't even know if that's what you are looking for, but pretty neat regardless...

[Italian LX]

http://www.corral.net/Tech/Engine/arm/arm

Just happened to see this today...
Yep, that was the only link I could find in reference to resistance of the RPM chips; however, his formula is waaaay off and nowhere near correct.

Desired RPM = (Resistance in ohms) + 1000

The equation he posted (quoted above) is linear equation and I have found out that the chips are only linear within each 1000rpm series.

It's a perfect example of why you shouldn't take everything you read on the internet as fact. I wonder how many people blew up their cars by using the wrong RPM value in their homemade nitrous switches. :rofl:


Although, other than the wrong reistance values, it's a pretty neat little tech article. ;)

[93Cobra#2771]

Well, that's some good info to know... :lol:

[joker]

A day late as always but I just now saw this thread. I had this from when i was looking into a window switch on the 96.

[Italian LX]

A day late as always but I just now saw this thread. I had this from when i was looking into a window switch on the 96.
Dude, you are the man!!!! :metal:

Thanks, Jason. :nice:

[joker]

No problem man, glad I could help.

[Scothew]

Sweet find Joker!