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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

wiring monster tach

  • Thread starter Thread starter myslo50
  • Start date Start date Jun 15, 2006

myslo50

Member
Jun 12, 2006
247
3
18
ohio
Jun 15, 2006
#1
  • Jun 15, 2006
  • #1
the white wire goes to the headlight switch, but which wire do i splice into

the red wire goes to the ign switch, what fuse can i put it into rather than the ign. switch.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jun 15, 2006
#2
  • Jun 15, 2006
  • #2
You can use fuse 13 for the lighting (this is the dimmer fuse). YOu can use almost any key-on 12 volt source for the tach - I let the mounting location determine what wire I would use.

If you choose to use a fuse for the power source, I would install a small fuse on your new power wire in the event of an issue with your new wire or the tach (so you dont blow the fuse you sourced power from).

Good luck.
 

Roland69

Sergeant Tangnet
Sep 17, 2005
2,867
2
58
Port Elgin, Ontario
Jun 15, 2006
#3
  • Jun 15, 2006
  • #3
I put my white wire to the fog light fuse (don't use my fog's they will start a fire lol)

I put my red wire to a fuse that was switched on with the key in the fuse pannel

I put the ground to the dash frame with a self tapping screw and it worked fine.

I put the green tach wire to the green wire with a yellow stripe from the coil..Just spliced it in so I have the stock tach aswell.
 

91lxttrim

New Member
Mar 7, 2006
194
0
0
AZ
Jun 15, 2006
#4
  • Jun 15, 2006
  • #4
Ever since I hooked my MSD BTM for the s/c, my tach is reading lower than the stock tach and when I get on it the needle is all over the place. I have it hooked up just like you Rolan, what gives?
 

Strype

Cuthbert catcher
Founding Member
May 11, 1999
61
34
104
Huntsvegas, AL
Jun 15, 2006
#5
  • Jun 15, 2006
  • #5
91lxttrim said:
Ever since I hooked my MSD BTM for the s/c, my tach is reading lower than the stock tach and when I get on it the needle is all over the place. I have it hooked up just like you Rolan, what gives?
Click to expand...

What is the BTM? If it has a harness to the coil, hook the tach up to the harness I would think. You don't want an MSD box going straight to the tach. I believe you're supposed to hook the tach up before the harness... anyone know


also try to ground the wire to the fender or somewhere instead of the dash panel
 

91lxttrim

New Member
Mar 7, 2006
194
0
0
AZ
Jun 15, 2006
#6
  • Jun 15, 2006
  • #6
The BTM is the Boost Timing Master that came with the Vortech s/c. It has a vacuum port to pull out timing according to boost levels.

So I still have the tach hooked up to the coil like before, should I try hooking it up to the MSD connector? The BTM came with a new harness that goes in between the coil and stock coil connector.
 

Codydubb

Member
Nov 3, 2011
149
9
18
Preston, Id
Dec 15, 2011
#7
  • Dec 15, 2011
  • #7
old post but good question do i hood my tach to the coil or to the msd btm??
 

Beasty306GT

Active Member
Dec 19, 2002
671
4
28
Oxford,Mass
Dec 15, 2011
#8
  • Dec 15, 2011
  • #8
Codydubb said:
old post but good question do i hood my tach to the coil or to the msd btm??
Click to expand...
you can hook it to the coil
 
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