HEI Tach adapter for Sun Super Tach?

[njsteve]

I just ran into the same problem installing the Super Tach II into my Gramma's Firebird with an HEI. GM made an HEI "filter" for its cars starting in 1975 to 1989 but it is no longer available new but you can find them in any GM car that had an HEI and a factory tach.

I saw several late model Monte Carlo SS's over the weekend at a cruise night and they all them, screwed to the firewall behind the dsitributor. It looks like an RFI filter that goes on the coil, but this actually is in line as the lead from the distributer to the tachometer. Several companies make them. Here is the guy I just bought one from.

http://rodneydickman.com/catalog/pro...roducts_id=265

I don't know what year your tach is but some very early ones won't function with modern electronic distributors.

[JRC99]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: njsteve</div><div class="ubbcode-body">I just ran into the same problem installing the Super Tach II into my Gramma's Firebird with an HEI. GM made an HEI &quot;filter&quot; for its cars starting in 1975 to 1989 but it is no longer available new but you can find them in any GM car that had an HEI and a factory tach.

I saw several late model Monte Carlo SS's over the weekend at a cruise night and they all them, screwed to the firewall behind the dsitributor. It looks like an RFI filter that goes on the coil, but this actually is in line as the lead from the distributer to the tachometer. Several companies make them. Here is the guy I just bought one from.

http://rodneydickman.com/catalog/pro...roducts_id=265

I don't know what year your tach is but some very early ones won't function with modern electronic distributors.

</div></div>

I'll check that out. The tach &quot;works&quot; so to speak, the needle moves and the light works, it's just inaccurate.

[njsteve]

When I first installed the tach last week it was &quot;jerky&quot; and would ratchet up with the RPMs or stop and hold at a certain spot. Not a smooth movement. Over a few days of driving it seems to have smoothed out. The filter arrives in a day or two and I will update as to what if any improvement in accuracy occurs.