has anyone installed a tachometer?

I want to know how many RPM I'm revving to when driving 100mph. :naughty:

What year is your car? I know many people putting tachs in there Crown Vics. Diffrent years calls for a diffrent way to hook up.

1998

if the vic is caborated it will be 5 grand when driving and when its in park it will go up to 6 1/2
fuel injected 4.6 v8 will rev up a grand higher than carborated. But if you have a 4.6 and wont to install a tack you can only run it to one of the packs and the idle will be jumpy ontile you give it gas. good luck, Roadkill(my name)

so it would affect my idle?

No it wont effect your idle the tack will just jump a little ontile you press on the gas because, the tack will only be hooked up to one coil pack. I hope this info was usefull (goodluck)

Why don't we accurately answer this guy's question?

First, which MODEL 1998 CV do you have? Does it have dual Exh? Because it DOES matter to which gears you have. The Single Exh has 2.73 gears, the dual cars have 3.27s. Your tires should be about 26.6" tall, and your OD is about 0.74 (4R70W). That's *about* 3617 in 3rd, and 2676 in OD with single exhaust. Multiply by 1.978 if you have dual exhaust.

Second, NEVER attach any wires to your coil modules. A 1998 Crown Vic has "Coil On Plug" ignition. The ONLY safe way to get a tach signal without using an inductive pickup on the primary ignition circuit is to get a signal generator and slave it off the crank sensor. They are available.

Third, a fuel injected 4.6L will NOT "rev up a grand higher" than a carbbed (box body) 5.0 will. Not at all. The 4.6L is electronically limited in these cars to about 6250 in "N" at WOT. They upshift at WOT at about 5600. Peak numbers are; Tq: 230 @3800, and Hp 165 @4200 (both rear wheel) stock. The 2001 up cars do about 20 Hp and 15 ft-lbs better.

"The 2001 up cars do about 20 Hp and 15 ft-lbs better."

How? ^

I guess I have the 2.73's.

thanks

They got the "Performance Improved" cylinder heads that FORD first put on the '99 Mustangs and '99 5.4L truck enignes in pick-ups.

Contrary to popular belief, there are exactly TWO modular camshaft profiles for the 2V engines. The Non-"PI" profile, and the "PI" profile (each with LH and RH cams of course). PI = Performance Improved, BTW.

So that's why 99 1/2 Expeditions have more power than earlier models? They also have PI heads?