Analog/digital tach replacement....ideas????

I have a simple engine/instrument setup, and want to lean accurately on the ground to reduce plug fouling, and airborne for the obvious reasons.
I have a single EGT, but the tiny 2" tach makes it tough to lean by rpm, or make fine adjustments.
I'd love a large analog tach to show trends, with a digital readout in the centre for accuracy. .... Nothing in the automotive, marine or racing world seems to fit the bill.
The odd one I've found that comes close, is over $400.
Are they worth it?

I replaced my analog tach with an EI digital and am very pleased with it. Yup, it cost about $400. The resolution is 10 rpm on the digital. I replaced the analog one because I learned it was reading 200 rpm high!

flyboy1963 said:

I have a simple engine/instrument setup, and want to lean accurately on the ground to reduce plug fouling, and airborne for the obvious reasons.
I have a single EGT, but the tiny 2" tach makes it tough to lean by rpm, or make fine adjustments.
I'd love a large analog tach to show trends, with a digital readout in the centre for accuracy. .... Nothing in the automotive, marine or racing world seems to fit the bill.
The odd one I've found that comes close, is over $400.
Are they worth it?

Click to expand...

Have you looked at MGL Avionics? Here's the site http://www.mglavionics.co.za/ Couple alternative choices in 2 1/4" (Infinity) and 3 1/8" (Velocity) round digital instruments. They do not have the analog/digital that you're wanting but I think they'll do nicely.

Tach ideas

Carlos,
I had NOT seen the MGL -Infinity stuff, it actually has a analog bar which would show the trends that I want, and looks reasonable at $165....depending on the sensor cost etc. thanks for the tip!!!

flyboy1963 said:

Carlos,
I had NOT seen the MGL -Infinity stuff, it actually has a analog bar which would show the trends that I want, and looks reasonable at $165....depending on the sensor cost etc. thanks for the tip!!!

Click to expand...

You can get away without a sensor. Some folks connect it to a mag-p lead, others seem successful wrapping a couple of turns of wire around a spark plug lead (I think that needs a bit of experimentation to get right).
Best solution that I know of is to use a UMA mag RPM pickup. This way you get RPM even during a mag-check so you can see the exact drop.
These instruments have a little trimmer accessible on the back with a small screw driver which allows the input circuit to be set to a wide range of sensitivities. In addition to that you can set the number of pulses per revolution that the instrument should expect.

Rainier
CEO MGL Avionics

Tachs

Rainier,
thanks for the info. I did a bit of research after my last comment, and saw that some people use one P-lead, or both, with some kind of switching, perhaps thru the ignition switch?
Evidently if I'd stayed in Electronics class in school, I'd know what a trimmer was also?!
Sounds like I'd get a bit of help from my builder or AME across the ramp to ensure I didn't end up with a live mag etc. after all the wiring work.

much appreciated,

VDO Industrial Tach

I used a 3000rpm VDO industrial tach, with hour meter I like it it can be driven many ways I drive it off my LSE (BTW if you have a LSE you can get a digital tach from Klaus) I like the round gauge
Peter