Hey,
Anybody got a picture of their tach filter wire going through the firewall on a 5th generation? I need to know which of the many factory dimples I need to drill out for this grommet. (Adding factory tach to a '79 with gauges, but no existing tach.)

On my car ('84) I poked the tach wire through the grommet around the steering column shaft. That way there's no holes to drill and seal in the firewall.

My tach filter has a very nice cone shaped rubber grommet on it. Looks like it would fit through about a 7/16" hole. There are several "predimpled" different places in the firewall which I know got drilled out from the factory as holes for various options. The rubber grommet will seal very well, as soon as I find out which one to drill.

Here is a picture of the tachometer filter and the firewall grommet in my 86 MCSS. When I put a tachometer in my 87 Elky I mounted it in the same location. Be careful you don't drill the hole too big.

http://elcaminocentral.com/users/elcamino/pics/tach_filter1.jpg

Anyone know the actual size of hole for the tach filter grommet? That would really help me before I start going hogwild with the drill. Thanks, Ben

Thanks Mr. Platinum Ernie G! That picture is just what I needed.

Boyd:
Does your factory tach match the year of your Elky? I've heard that in some of the earlier models (78-81) the circuit board on the back of the tach doesn't match the later years, thus if you get a tach from an '86 it's not compatible with an '81 Elky?

I'm interested in replacing the Non-Functioning Quartz Clock in my '81 with a factory tach but have heard that unless the tach is compatible with the Elky it won't work.

Anybody know for sure?

78-85 tachometers have a clock in them that sticks out the back.

http://elcaminocentral.com/users/elcamino/pics/78_85_tach_back.jpg

86-88 tachometers do not.

http://elcaminocentral.com/users/elcamino/pics/18_pin_con.jpg

I'm pretty sure the flexable circuit board on the back of the gauge pod is the same.

Ernie,
The tach I bought has the clock, and is supposed to be correct for my year. (1979) As for knowing whether it works right or not, we are a LONG way from finding that out! (Still in several hundred pieces in two different buildings.)