V8-Ranger.com

I noticed a link to a v8 tach module on one of the front pages here, how does one go about getting one of these?

I don't know if Malcolm still makes those. I've just been running my V6 tach for quite some time as-is and made peace with the fact that it's off by about 25%. I do have a logic diagram with flip-flops that basically do the same thing his device does if you want to make one of your own. It's only a few components that are readily available from Digikey. If you have a Radioshack, you might be able to find them there too. I don't know. If he no longer sells his, I'll see if I can dig up my schematic, put it into Visio, and post it here. The schematic includes a simple jumper option to select whether you have a 6cyl or 4 cyl tach.

Thanks, when you have time please and I do appreciate it. I'm no stranger to a soldering iron but since radio shack is belly up it will be almost impossible to find one.

I find digikey a bit pricey and have company accounts at mouser and RS.

For due respect since I have already e-mailed Malcolm when I had a nearly impossible time registering if he has one left and don't have to make it I probably should buy it you think? I just don't want to step on toes at any price I'm like that.

EVTM's on the way from e-bay for both 2000 ranger and donor 97 mountaineer, perhaps some clues in there also.

If he has some avail, yea get one from him. I don't know, but I'm betting he hasn't sold that many of them. These just aren't commonly needed devices for the average motor head. They are quite specialized.

As for the EVTMs, I found mine relatively useless. I got everything I needed from wiring diagrams of my year Ranger.

The wiring harness I had didn't match anything I had diagrams for, so I just did a point-to-point on it, wrote down colors and what pins they went to on the EEC. I went to a junk yard and clipped every connector I would need from a similar year Ranger to make my V8 harness plug right into my Ranger's chassis connectors. Then I started hacking it all together.

When the time came, the most annoying part was bundling the "extra" wire back into the loom...and "wire-stretching" the connectors I didn't give myself enough length on to reach. But it did plug right in.

I thought the EVTM had wiring diagrams in it? DO'H!

It has some wiring, but they are more a conceptual wiring schematic. They are not nearly as detailed as the actual Ford publications called "wiring diagrams".

Ford Wiring Diagrams include things like wire color, the type/shape & pin number of the connector the wire connects to, as well as places where the wire might be factory-spliced into another wire. If your harness matches the diagrams, the wiring diagrams leave no doubt as to what wire is what, where it goes, and what it connects to. They are quite thorough and useful...if the diagram you have exactly matches year/model of your actual application. A year off, and connectors & colors MIGHT not be the same particularly if you are off by a year Ford made significant changes (i.e. 88 to 89 Mustang or 92 to 93 Ranger).

Here's the logic I came up with if I were going to make one of these devices. If there are additional resistors, inductors, or caps necessary to work correctly, I don't have the Electrical Engineering knowledge to know about those things. If I were going to breadboard such a device, I'd start with these components.

The signal voltage converters, I'm assuming would be needed to convert whatever voltage the tach signal is at to/from TTL levels (usually in the 3.3v range). If the signal is already in the 5v range, then no conversion is likely needed at all.

Cool thank you, the first time I looked in the flow chart was not there, I see it now.

Both my manuals came in, the ranger manual was labeled "wiring diagrams" but both the ranger book and the mountaineer book are filled with useful "stuff" for lack of better terms.

When it gets closer to this phase of the project I'll definitely post what I did but I bet I have to weather an initial couple weeks of bashed fingers and rusted bolts before I get to the fun stuff.

Well I decided not to do this... I guess I didn't notice my particular dash cluster simply does not have a tach. Duh.

The donor mountaineer does though.

Just noticed this thread and no sorry I don't make these anymore. Been many years since I did. I doubt I even have schematic I designed back in the day anymore but I can dig around. The concept is to basically build a frequency counter and generator and adjust the math accordingly. A V8 will produce X number of tach pulses per RPM and the V6 tach only expects to see Y tach pulses for the same RPM.

A more simplistic approach would be to take a simple decade counter circuit and just drop every 4th pulse. It would get the right number of pulses out but they'll be staggered in groups of 3 with a missing pulse or pause. It works but the needle will have a little bit of fluctuation or jitter at lower RPMs. That was how I did my original prototype to test the concept before building the frequency counter/generator version.

So your later design was more advanced than what I diagrammed above?

I can't see your diagram above. Says I'm not authorized to view.

That's odd. It's linked to a picture I uploaded to eectuning.org since I can't attach files on this forum. Although I don't think there is any kind of restrictions on it. Try this:

• Browse to eectuning.org
• Logout if logged in automatically
• Try to view this link: http://eectuning.org/forums/download/file.php?id=4112

Had to logout of eecturning.org to view it. Interesting. Very different approach than what I took. How does that method work?

Best I can figure is it has to do with where I posted the picture (where most members can't access). But I would've guessed that users not logged in would also not be able to see it. But it appears they can...at least pictures. I bet that's a phpBB bug.