Supercharger, Part IX: Ignition Boost
Paradise Garage




 Related Pages
 Reciprocal Links

We recommend Internet Explorer set to 1024x768.

© 2001 Brian F. Schreurs
Even we have a disclaimer.

Come on baby ignite my fuel.


Buy our book!
 With all this extra supercharged power available to the Paradise Garage Mustang GT, it's not the best idea to trust the engine computer to figure out what to do with it. Vortech appreciates this and includes an ignition/boost retard unit. The unit, called a boost timing master (BTM), is actually manufactured by MSD. Vortech provides instructions for hooking it up, but they leave the location up to the installer.

Vortech actually makes this part relatively easy, a nice change of pace from some of their earlier steps. Start off by hooking up the adapter wiring. There's a plug on the ignition coil -- disconnect it, insert an adapter provided by Vortech, and reconnect the harness to the other side of the adapter.

We mounted the boost timing master on the firewall near the master cylinder. It was the last brick-sized flat surface left.
Find a place to mount the boost timing master. It's about the size of a brick, so finding a place for it to go in the crowded Mustang engine bay is no easy task. To complicate matters, this toy doesn't like getting too hot, so mounting it anyplace close to the engine is out of the question. We finally settled on a piece of turf along the firewall. Drill four holes into the wall and use the provided hardware. Be sure to mount the box with the aluminum cover on the bottom.

Now, the box has to be grounded. There are a ton of great opportunities to mount a ground wire in an engine bay, but we already have a bunch of custom wiring in there so we just patched into the existing ground wires. If you don't have this option, just check the wiring diagrams for a nearby ground point and run the wire to that.

Next, find a place to mount the boost control knob. We decided to mount it right on the dash, on a blank piece of trim just to the right of the gauges.

The dash has to come apart anyway, to route the wiring through the Mystery Grommet in the firewall. To get the front fascia off, you must first remove the headlight knob. Pull the knob to its full-open position and look for a slit near the base. Supposedly there's some sort of clip in there that you just loosen with a pick or punch, but we dunno. We just fiddled with it for about a half hour till it fell off. It'd probably be easier to just buy a new one and break the old one off.

With the headlight knob out of the way, it's possible to pull the fascia off. It's held in place by two Torx bolts, size T-15. They are located along the upper edge. With those removed, gently pry the fascia off.

At left are the vacuum lines at the fuel management unit, and above are the vacuum lines at the adjustable fuel pressure regulator. They are connected using brass fittings and nylon zip ties. These must be attached in the correct order to keep everything working.
The knob itself sticks in place with tape, but the tape really isn't strong enough to hold the knob into place. We ended up having to use crazy glue. Be sure that it starts out set at 3. The knob connects to the box with a connector. Easy.

And now it's time to make sense of the rat's nest of vacuum hose. The order goes like this:

  • FMU on passenger fender
  • ignition/boost control, 4" from the FMU
  • bypass valve, 8" from the FMU
  • fuel pressure regulator, 8" from the manifold vacuum tree
  • boost gauge, 4" from the manifold vacuum tree
And with the vacuum lines all plugged in, everything under the hood is done!

But we're not completely done yet. It'd suck to go to all this trouble, only to melt a piston from lack of fuel. The 190-lph in-tank fuel pump went a long way to help with this, but just to be especially safe, we also installed a T-Rex external fuel pump.