tachometer dropping out ??? [Archive] - Chevelle Tech

: tachometer dropping out ???


71stroker
Apr 19th, 09, 10:11 PM
Well I can't seem to find this question asked before soo...

My tack is completely dropping to 0 at wot anywhere over 4000 rpm ,as soon as i let off the throttle it comes right back to life. I'm using MSD distributer and a factory tack in a 71 Velle. any ideas? thanks, Doug

Bob's66396
Apr 20th, 09, 8:15 AM
Doug, I'm not exactly sure if this is any help,But don't you have to have an adapter for the HEI to run the tach?...Bob

71stroker
Apr 20th, 09, 10:50 PM
Doug, I'm not exactly sure if this is any help,But don't you have to have an adapter for the HEI to run the tach?...Bob

Well Bob you may have something there! What kind of adapter? The wiring harness was ordered from M&H for the HEI ignition , but thats just the harness plug. Hmmm anyone else????

Bob's66396
Apr 20th, 09, 11:14 PM
Doug, You can check with Summit,Jegs,or even OPG. I believe they all sell that adapter..Bob

lowrollin70gmc
Apr 21st, 09, 12:19 AM
Also make sure your tach is grounded well, as they can jump around if they have a crappy ground. Or was I actually running 8000 rpm???