Electronic Tach conversion

[Wamp]

I just bought electronic tach to convert my 74 cable tach over. I have the pin out for the tach. Three pins (far left) 12Volt power, (far right) Ground, and (bottom left) to Hei. My question is, the 12 volt what fuseable link should I run this too? Pricey little item, want to protect it at fuse panel. Next, until I switch over to MSD distributor and 6A box (which I have been told is just a plug in for this tach. Can I run it to coil in the mean time?


wamp
74 coupe

 

[fc3]

Wamp, Who made the conversion? Where did you buy it? Does it use the original dash gauge? Sorry I can't help but I am interested how it all works out. My 72 is cable driven as well. Good luck! Fred.

 

[Wamp]

77 tach

It's a stock 76 or 77 tach, can't remember. I opened it up and there is no burn marks, so assuming it's in good working order. I have read on posts that it will hook up to the 6A box. I hate the distributor that's on there now. I rebuilt it, so the only thing original is the housing. I should of threw it away and went with the MSD pro billet from the start. I have an under the dash leak, so have to rip out dash yet again, was gonna stick new tach in at that time, cant afford the new ignition quit yet. Have had nothing but problems with that tach drive cable, think I over shimmed distro during rebuild so it's not aligned right with tach gears.

wamp

 

[Wamp]

MSD

Not getting any replys on this. I have emailed MSD, hate to order something exspensive to find out I coulda done better. Heres my Idea:

MSD probillet Distributor: want one with out mechanical tach hook up. If I do get the corvette distributor w/ mechanical tach hook up can I plug the tach hook-up and remove gears? what type of advance do I want?

MSD 6AL ignition control box (pn:6420)

MSD Blaster HEI Coil (pn:31769) is there any better or is this a match? To many choices.

Hook up electronic tach and run tach output to 6AL box.

Any suggestions on plug wires? Engine is stock so far with hooker sidemount headers. Will be upgrading engine and transferring ignition over to crate engine when the money is right.

 

[Jack]

/wamp ... Can I run it to coil in the mean time?

In mean time: Yes, run tach's trigger wire to coil's negative (-) post. Leave plenty of wire so you can run to msd box if get one.

For later: The MSD 6 boxes have a wire that is specific to trigger a tach ... no problem ... just connect that trigger wire from tach that you left plenty long.

My question: Do you presently have a points-type distributor ... or has it been retrofitted w/ a chevy HEI?

MSD Blaster HEI Coil (pn:31769) is there any better or is this a match? To many choices.

Are you sure of this pn ? ... doesn't look like MSD pn for MSD coil.

MSD 8203 is Blaster oil-filled canister style--must mount vertical
MSD 8222 is Blaster High-Vibration epoxy-filled canister style--mount any way
(I have an xtra, new in pack 8222 I don't need ... $30 vs $40)
MSD 8225 fits into top of GM HEI distributor cap--mount in cap
MSD 8252 is HVC e-core--mount any way

I’m gonna run MSD HVC pro box 6600 & cap conversion pn 8401 & pro HVC coil pn 8250 w/ gutted GM HEI & Accel 300+ 8.8 wires with 75 tach in my 71.

I'm sorta 90% there on my setup ... go ahead & ask q's. I also have a few other MSD pieces for sale including an xtra, good used 6 box (nascar 6TN pn 6401) & an xtra, new conversion to run outside coil w/ HEI (pn 8401). Have an xtra set of new Accel 300+ ferrospiro 8.8mm wires too.
JACK:gap