Caprice Mods

What do you do with an LT1-based Caprice? You modify it, of course. There's a healthy aftermarket for the Impala SS, and most everything bolts onto the 9C1.

Keep in mind that because this is a 9C1, it already comes standard with several things Impala owners add to their cars, including:

• Auxiliary engine oil and power steering coolers
• Improved air dam (for redirecting cold air to the front brakes)
• Brake dust shields (in conjunction with the air dam)
• Full set of body/frame bushings in all seven pairs of mount points, to aid in body flex control. Impalas and civilian Caprices only received bushings in four mount point pairs.
• Lifetime silicone rubber coolant hoses (easily spotted because of their green color)

The 9C1's suspension is also set up to be the stiffest suspension offered on the B-body sedan platform. It's obvious that Chevrolet meant business when they specified Bilstein shocks to be used at all four corners of the car.

Even so, there are still plenty of upgrades and modifications that can be done to this car. My planned mods aren't all that exotic compared to some of the other Caprices and Impalas out there.

These are mods I've already done:

Performance

• K&N air filter
• MSD Blaster ignition coil
• Taylor 8mm silicone plug wires
• Drilled out airbox in front, bottom, and along left-hand side
• "Home plate" delete (I used an ABS sewer plug - $1.06 from Home Depot)
• AIR pump delete (before you tree-huggers start grousing, GM got an exemption from the EPA because the AIR pump wasn't necessary to meet federal smog requirements, so it's legal, plus it also declutters the engine bay)
• Performance Friction Carbon Metallic brake pads

• High-torque Corvette starter

  

  This is the old fragged starter:

  

I've also removed the first-gear lockout bracket from the transmission.

Interior

• Replaced humongous GM airbag wheel with a Grant Challenger steering wheel. A standard Grant adapter for the generic 70s-90s tilt column worked, although the tilt housing is about a half-inch taller, requiring clearancing of the Grant metal trim 'bell.' Loose tilt column tightened as well.
• Reconnected rear door lock/unlock and opening mechanisms
• Reconnected rear window up/down switches
• Reconnected door jamb switches for interior light
• Recentered passenger front seat (found build sheet!)
• Replaced stock AM/FM radio with a Pioneer KEH-P4400 head unit
• Realistic PRO-2026 scanner mounted in place of ashtray
• TSI "Clutter Catcher" console ($25 at Wal-Mart)

Exterior

• Rewired wimpy headlamp wiring harness to handle high current via relay actuation; replaced Wagner 9004 bulbs with Sylvania XtraVision units (blue lights are junk, but you already know that)
• Taillight blackout (chrome trim and recessed horizontal ribs painted black)

Near-future mods (as time and money permit)

I just (May 2006) acquired a cruise control unit, throttle cable, harness plug and steering column lever from a '94 Buick Roadmaster for $30. The only things left I need are a brake switch for the cruise control release and to fabricate a wiring harness. Fortunately the lever wiring is already present inside the steering column.

• "First base" delete and MAF relocation
• 9C1 deflector dam installation (I'm missing all three pieces!)
• Driver-side spotlight addition - maybe. There's some douchebags running around locally impersonating police vehicles right now and I've already been pulled over once at 2am just so the real police could check me out. Probably don't need the 'extra' attention.
• Installation of amateur radio gear (and 11m gear for highway use)
• "Stealth bolt" brake proportioning upgrade.
• 9C1 wipers (for some reason, I have regular wipers on there now)

Past non-mod repairs

• Fuel pump (twice) - stick with AC-Delco pumps. The cheap imported pump I had put on only lasted a noisy year and a half.

• Water pump (twice) - they seem to fail around every hundred thousand miles or so.

• Transmission - Rebuilt by AAMCO about a hundred thousand miles ago. Still holding up so far.

• Optispark - failed at 215,000 miles from oil infiltration through the optical pickup plug (there's a rubber seal on the Weatherpak connector but it's not very effective). New water pump and Optispark drive seals in the timing cover were also replaced, since one of them was the source of the oil leak which caused the Opti to fail.

• Ignition system - replaced soon after the Optispark. Ignition coil and wires were upgraded but it also got a new stock ignition module and Autolite AP106 platinum plugs.

• Brakes - new Timken wheel bearings, stock rotors and hoses, loaded Raybestos calipers up front. Now running Performance Friction Carbon Metallics on all four corners.

• Window Rollers - since the old ones were of a weak design and broke on all four windows.

• Battery - desert heat is tough on 'em. AutoZone DuraLasts hold up pretty well and the warranty on 'em is prorated.

Imminent repairs

• EGR valve and solenoid - the original ones cause a part-throttle surge between 45-50mph.

• Air conditioning - it's got at least one leak and won't hold a charge.

• Front Suspension - the current parts are past old and worn. The steering floats at speed and the front suspension clunks over bumps now. The sway bar end links shed their rubber bushings a long time ago and have already egged out the control arm mounting holes.

• Harmonic balancer - the existing one's currently in the process of shedding its rubber insulator.

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