uh..i don't think there is much unless you have the tools to remove the exhaust resonator yourself and happen to have some 1-3/4" straight pipe lying around.
gutting the cat is always free.
forcing air into the intake is also free if you have the right tubing and harware.
can't think of much else.
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1995 GL Zetec MTX...Light Blue
Born: July 1995 Purchased: November 1997
KKM Intake
Superchip
FocusSport Ignition Wires
Autolite Platinum Pro Plugs
WINTER PAWS: Blizzaks on stock 14 inchers!!! Bring on the snow!
Viper 500+ Alarm
Sounds by: Pioneer CD/Polk dB/MTX Subs/Alpine Amp
Richbrook Shift Knob
"Recontented" Foggies