Dashboard Timing Display for Hot Rod

I think the easiest thing to do would be to calibrate a vacuum gauge to read timing.

It all depends on throttle position, and that says vacuum, above some known RPM, if you have a mechanical advance.

I'm sure there are other ways to do it.

Adjustable Timing Control Part number: 8680 The MSD Adjustable Timing Control puts you in control of your ignition timing from the driver's seat! A dash-mounted control knob allows you to adjust (...)


http://www.msdignition.com/products/rpm_timing_controls/timing_controls/

I've got the Crane version, neither one has a display gauge though. Installing that unit was one of the best things I've done for my old truck.

Whatya advance it when yer haulin stuff er what?

I think it shifts the timing proportionally to the rotor's pick-up frequency; but you have also the option of using the dial for added (or subtracted) time, I guess it'll help during cold mornings. I need one of those, I have the MSD basic unit and it does wonders for my in-line 6.

As per the OP's question, you could use a DSO to meassure period between rising of the pick-up pulse and rising of the ignition pulse.

Regards

I actually bought the Crane ignition so I could eliminate the stock HEI ignition module in the base of the distributor. It's a 1986 GMC with a 454 motor. The ignition modules I could find were cheap Chinese junk and kept going bad.

The optional timing adjustment knob was pretty reasonable so I went ahead and got it..................mounts right on the dash. Yeah, I find myself tweaking it a little with almost every tank of gas. Since the new cars are continually self adjusting, I'm pretty sure that fuel quality has gone down.................there's also the ethanol factor.

I installed the MSD 6200 along with the adjustable timing control and Accell coil in a Dodge van. I would use the dial to find the highest speed when the throttle was held steady. Loved it. I also used the duel pickup from the lean burn engines, and left it connected to the original firewall control unit. It would allow an easy switch in case of a failure.

This site has lots of gauges. Will a vacuum gauge work?

A vacuum gauge would only give the advance component due to vacuum, assuming you could calibrate the gauge in advance degrees. The other parts of advance are initial and RPM. If we could get the elapsed time between cylinder #1 firing and TDC, that could be massaged to drive a display. TDC could be had with a crank trigger, but I was hoping to avoid adding or changing hardware on the motor.

Yes, right, but once your engine gets to 2,500RPM or so the mechanical advance is at maximum advance and no longer varies.

Maybe the vacuum gauge won't work for you, just a thought.

Vacuum gauges suck.

Sorry, here's the link.

Wow, that is a great little gadget. I might get one of those so I don't have to lug my Tektronix 465B anchor around. Thanks!

Does your hotrod donk have an ECU with OBDII or is it all mechanical feedback and control?

If it has OBDII then the timing data (and the rest) is extractable for display however you want it.

Here is one out of the box http://www.aeroforcetech.com/products_interceptor.html

There are also schmutt-fone apps and dongles available.

If it is not ECU controlled then you should get in touch with antique hotrod operators to see what they did...A strobe light and a CCTV would work.

A vacuum gauge will tell you what the manifold vacuum is. A timing assertion from this assumes all is working per calibration and is not a real time positive revertive ignition timing reading.

What type of ignition timing system do you have? MSD sells a crank trigger that could be used to determine TDC, and then pull a signal from the ignition system that you have. That would give you the two signals needed to show actual engine timing. How to get it to show on a gauge is above my skills, but it should not be that tough. Good luck.

Hi Bob! (homage to my favorite TV show of all time). I have a Mallory MaxFire programmable distributor. There are distributors made for EFI applications that output a "cam sync" signal and that could do the job too, but I don't want to change distributors. The crank trigger is the most direct approach to getting a TDC signal. I'm still trying to figure a way to get it without more hardware. And getting the result on a gauge will take some circuitry. I can do it in analog (I'm old school), and I know it could be done in digital too.

Optical...I hadn't thought of that. Lots of cheap and easy ways to implement that. The aftermarket crank triggers are over $200 and take up lots of space. You get a GA.

How about a flip-flop that sets when #1 fires and resets at TDC? The output would be a square wave with a duty cycle proportional to advance. A little massaging and I'd have a signal to go to a dash volt meter calibrated in degrees of advance.

A little massaging and I will be fast asleep.

I do like the idea of a photo-electrical. It eliminates the need for close proximity. Just find a convenient spot to mount the sensor, and bring the engine to TDC, and stick a piece of reflective tape on the balancer in line with it. GA.

I like the idea of pulse width to analog gauge! Simple, cheap, kinda fun to play around with resistors and caps to get it to read right.

Send pictures, and let us know what you did, once the project's done.

Good luck.

I am redoing the induction this winter and will incorporate this into the project. Thanks to all for the good ideas and I'll post the results.

I wanted a meter to match my other meters and there it is already in the dash! I was going to replace it anyway with a digital display in the console, so I'll crack it, gut it and use the movement. Relabel the face, add my circuitry and it'll look like an OEM Autometer. That should get some looks and questions.

I have a design for my meter: Timing display

I'll be most interested in your suggestions, questions, etc.