1 (edited by Crazybob 2021-11-15 10:10 AM)

Topic: Tach install on ecotec swap

Sorry but I’m a total idiot when it comes to anything electrical.
Against our better judgement we swapped in a 2.4L LE5 into our NA Miata.
I just want a tach. The inter webs said to get an MSD tach driver like the 8913 and use it to drive a tachometer and everything will be easy button.
I’ve got the MSD box wired between what should be the 12v wire to the #4 coil and I have it running a cheapo Autogage tach with a shift light. All I can make it do is sporadically give a reading between 500 and 1000 rpm. Granted that tach has been in a box for a couple years and all the connections are just twisted together to see if it would work before I start soldering stuff. But that still seems wrong.
What obvious dumbass thing am I doing?

Emily's Power for a Cure 1990 Mazda Miata (I Got Screwed 2014 Southern Discomfort)
Help in the fight against Neuroblastoma, a devastating childhood cancer.
http://emilyspowerforacure.com/

Re: Tach install on ecotec swap

This probably isn't the right answer, but I'm pretty sure every aftermarket tach has a setting to tell it if it's a 4/6/8/etc cylinder. Are you sure that you set that up correctly?

Full Ass Racing
#455 Piñata Miata

Re: Tach install on ecotec swap

I did set the little dongles to 4 cylinder. I also tried every other setting.

Emily's Power for a Cure 1990 Mazda Miata (I Got Screwed 2014 Southern Discomfort)
Help in the fight against Neuroblastoma, a devastating childhood cancer.
http://emilyspowerforacure.com/

Re: Tach install on ecotec swap

I ran this same set up on my L61 with the Distributorless Tach Driver - PN 8913 and it worked ok, now with LE5 the harness I got came with a nice tach output wire. We did have to screw around with the settings on the tach.

Apocalyptic Racing - Occupy Pit Lane racing
Racing the "Toylet" Toyota Celica powered by Chevrolet Ecotec.
24x Loser with the Celica. 16x loser in other fine machines
Overall winner Gingerman 2019