Tach reading high

[4spdragtop]

I might not be the best student, but I'm trying lol. What initially was a carb issue that I was wrestling with, then this damned "tach issue". I've gradually worked my way back to it looking like a connection/ supply voltage issue at the ignition switch "area".
With that being said, while trying to diagnose, I noticed that the fusible link I installed while doing Mad Bypass a couple years back was undersized. Its 18 ga now and Mad Bypass suggests 16ga. I initially ran the 18 ga from starter relay to under the dash where I connected it to both large red and black wires for Mad Bypass.
Long winded, but what length should the fusible link be?
All the connections were a crimp/solder deal that I thought were all good, but there are several of them and am going to minimize what I can while I'm upside down lol.
Thanks
Steve

 

[4spdragtop]

So, took for a couple short(20 min) evening test drives. I guess the neighbours got tired of hearing/smelling this thing idling as the Bylaw officer paid a visit. I was at work so Lori "handled" it lol.
Anyway, 2 test drives all appears good. 1st drive had a couple slight "stumbles".
2nd one nada. I'll take it for another run tonight after work.
To summarize what I did,(so far lol)
-Replaced ecu harness, thanks @Wire !!
-Replaced 2 undersized fusible links.
-Shortened blue coil +ve wire by about 18"(not sure why it was so long)
- replaced and moved Black/Red Mad bypass splice to engine bay instead of underdash.
-redid a couple of other solder connections while I was under dash.
So still have to reinstall ac diffuser, triple gauges and tidy up wiring.
Fingers crossed and then onto tuning the carb(again)
Thanks for all the help/advice!
Out for test drive the other night I was turning around at a quarry and thought the moon looked cool.
Looked better in person.

 

[67Dart273]

I might not be the best student, but I'm trying lol. What initially was a carb issue that I was wrestling with, then this damned "tach issue". I've gradually worked my way back to it looking like a connection/ supply voltage issue at the ignition switch "area".
With that being said, while trying to diagnose, I noticed that the fusible link I installed while doing Mad Bypass a couple years back was undersized. Its 18 ga now and Mad Bypass suggests 16ga. I initially ran the 18 ga from starter relay to under the dash where I connected it to both large red and black wires for Mad Bypass.
Long winded, but what length should the fusible link be?
All the connections were a crimp/solder deal that I thought were all good, but there are several of them and am going to minimize what I can while I'm upside down lol.
Thanks
Steve

View attachment 1716144340

I would not make it too long. "Let's say" max of maybe 3"

 

[4spdragtop]

Thanks Del, its approx 9-10", I'll check after work. Now that I redid the black and red large wires, i dont think there is any slack left in them to be able to shorten the FL.

I would not make it too long. "Let's say" max of maybe 3"