Rusty Shackelford
Inactive
What do you think??
The 9C1 Difference
Note: the following information mainly pertains to the '95 9C1 Caprice, and may or may not be relevant to earlier or later year models. Even so, don't take any of the facts here as gospel - this was mostly from memory, and I might have some of the facts wrong.
This Isn't Your Grandfather's Caprice!
For those of you who might be unfamiliar with a '9C1' Caprice, here's the basic story. The code '9C1' is a decades-old GM option code designating a group of Special Equipment Options for the manufacture of a police fleet vehicle. There are several of these 'SEO' options that separates the 9C1 from the regular granny Caprices.
The first big item is the motor. My 9C1 is home to the LT1 350 engine (supposedly a 'corporate' engine, but give us a break, it's a small-block Chevy), derived from the LT1s used in the Corvette. (This motor is radically different from, and should not be confused with, the early-70's "LT-1" motors Chevy used to build!) GM used a different camshaft in the Caprice than in the Corvette, bringing maximum horsepower down from 305 to 260, but adding more torque in the process. The Caprice LT1 also got iron heads (essentially Vortec heads with an intake bolt pattern unique to the LT1) rather than the aluminum heads of the 'Vette's LT1 (but which outflow the aluminum pieces by 20cfm!), and a two-bolt block instead of the 4-bolt 'Vette motor. These motors were options for the civilian Caprice, but they were limited by the computers to 105mph. The police cars generally have no such restriction, and at stock power levels are drag-limited to a 135mph top speed.
The LT1 itself is a marvel of engineering. GM realized that compression could be raised without detonation/knock problems if the cool water from the radiator was first routed to the heads instead of to the cylinder water jacket. This required a redesign of the block, heads, and intake manifold, but resulted in a 'reverse-flow' cooling system which provides superior engine cooling. (Who else can run 10.5:1 compression on 87 octane without knocking?) Along the way, they redesigned the water pump to be driven off the camshaft rather than by a serpentine belt. This adds reliability to the pump (since bearings are no longer side-loaded, they last longer) and to the car itself (since the car can run without overheating even if the serpentine belt is lost). Because the coolant enters through the heads and returns directly to the water pump, the coolant crossover pipe in the intake manifold can be eliminated.
There are other features in the engine compartment besides the motor that set the 9C1 apart from the civilian Caprice. The coolant hoses are made of 100% silicone rubber, will last the lifetime of the car, and have a truly unique bright green color. The hose clamps are 100% stainless steel and have solid backings to prevent the hose from extruding through the slots. Auxiliary engine oil, transmission oil, and power steering coolers help keep essential lubricants cool during high-speed pursuits. The lower air dam was redesigned to direct air flow to the front brakes, keeping them cooler and free of dust.
Behind the motor is a 4L60E 4-speed overdrive automatic transmission (the latest rendition of the venerable TH700-R4) with a 0.7:1 ratio overdrive. The 9C1 (and Impala SS) can run at high speeds in overdrive, unlike the civilian Caprice, which will downshift to third gear. The torque converter has a higher-than-stock stall speed, and the shift characteristics are also reprogrammed for more performance. The motor itself breathes through a true dual-exhaust system - each side has its own cat, muffler, and resonator. Power is transmitted through a limited-slip 'posi' rear end with 3.08:1 gears.
The chassis is also different. The frame for the 9C1 Caprice (and the derivative Impala SS) is made from a thicker gauge of steel than the civilian Caprice. In addition, body/frame bushings are present at all 14 body/frame mounting points (on the civilian Caprice and Impala SS, GM left out three pairs of bushings), resulting in less body roll. The springs are also much stiffer, as are the stock Bilstein shocks. You can't see them through the steel wheels, but there are disc brakes at all four corners of the car, with the front calipers wearing thicker pads than the civilian Caprice and Impala SS. You can, however, see the beefy rear anti-sway bar hanging below the rear axle.
The 9C1 wears steel wheels since because of the rear disc brakes, standard Caprice rims will not fit the rear axle. (The Impala SS copes by going to alloy 17" rims.) The strength of the steel wheels, though, combined with the stiff suspension, LT1 power, and heavy-duty cooling, give the 9C1 a towing capacity of 5000 pounds. (Because of the softer suspension and alloy rims, the Impala is rated at 2000 pounds, though many Impala owners swap rims with the 9C1 units and tow much heavier loads.)
The interior bears some differences too.
Law enforcement agencies had a fair amount of variety in selecting interior packages, and I got what is probably pretty representative of the common selections. The front bucket seats are made with heavier cloth and thicker foam to hold up better to wear, and with armor plate in the backs to prevent occupants from being stabbed. The rear bench seat, though is vinyl, and the floor is covered in black rubber in lieu of carpet. In addition to the stock dome light, there's also a 'ticket-writing' light located up front. There's a switch on the dash to turn off the dash lights.
Speaking of interior lights, the cars ship with the dome light disabled at the door switches. The rear door linkages also ship in a state of incompleteness, and the window switches aren't hooked up at all.
The passenger seat also sits on a factory bracket which offsets it to the right just enough for an aftermarket police console to fit in between the front seats.
All this adds up to a pretty quick car for its size. In stock form, I've run a best (uncorrected) 1/4 mile time of 15.875@87.75 mph (with a cracked flexplate, shot torque converter, and dirty air cleaner!). Keep in mind that this is a 4200+ lb. beast running in 95-degree temperatures at a 3800' Ft.
All of this for 3000-4000$
The 9C1 Difference
Note: the following information mainly pertains to the '95 9C1 Caprice, and may or may not be relevant to earlier or later year models. Even so, don't take any of the facts here as gospel - this was mostly from memory, and I might have some of the facts wrong.
This Isn't Your Grandfather's Caprice!
For those of you who might be unfamiliar with a '9C1' Caprice, here's the basic story. The code '9C1' is a decades-old GM option code designating a group of Special Equipment Options for the manufacture of a police fleet vehicle. There are several of these 'SEO' options that separates the 9C1 from the regular granny Caprices.
The first big item is the motor. My 9C1 is home to the LT1 350 engine (supposedly a 'corporate' engine, but give us a break, it's a small-block Chevy), derived from the LT1s used in the Corvette. (This motor is radically different from, and should not be confused with, the early-70's "LT-1" motors Chevy used to build!) GM used a different camshaft in the Caprice than in the Corvette, bringing maximum horsepower down from 305 to 260, but adding more torque in the process. The Caprice LT1 also got iron heads (essentially Vortec heads with an intake bolt pattern unique to the LT1) rather than the aluminum heads of the 'Vette's LT1 (but which outflow the aluminum pieces by 20cfm!), and a two-bolt block instead of the 4-bolt 'Vette motor. These motors were options for the civilian Caprice, but they were limited by the computers to 105mph. The police cars generally have no such restriction, and at stock power levels are drag-limited to a 135mph top speed.
The LT1 itself is a marvel of engineering. GM realized that compression could be raised without detonation/knock problems if the cool water from the radiator was first routed to the heads instead of to the cylinder water jacket. This required a redesign of the block, heads, and intake manifold, but resulted in a 'reverse-flow' cooling system which provides superior engine cooling. (Who else can run 10.5:1 compression on 87 octane without knocking?) Along the way, they redesigned the water pump to be driven off the camshaft rather than by a serpentine belt. This adds reliability to the pump (since bearings are no longer side-loaded, they last longer) and to the car itself (since the car can run without overheating even if the serpentine belt is lost). Because the coolant enters through the heads and returns directly to the water pump, the coolant crossover pipe in the intake manifold can be eliminated.
There are other features in the engine compartment besides the motor that set the 9C1 apart from the civilian Caprice. The coolant hoses are made of 100% silicone rubber, will last the lifetime of the car, and have a truly unique bright green color. The hose clamps are 100% stainless steel and have solid backings to prevent the hose from extruding through the slots. Auxiliary engine oil, transmission oil, and power steering coolers help keep essential lubricants cool during high-speed pursuits. The lower air dam was redesigned to direct air flow to the front brakes, keeping them cooler and free of dust.
Behind the motor is a 4L60E 4-speed overdrive automatic transmission (the latest rendition of the venerable TH700-R4) with a 0.7:1 ratio overdrive. The 9C1 (and Impala SS) can run at high speeds in overdrive, unlike the civilian Caprice, which will downshift to third gear. The torque converter has a higher-than-stock stall speed, and the shift characteristics are also reprogrammed for more performance. The motor itself breathes through a true dual-exhaust system - each side has its own cat, muffler, and resonator. Power is transmitted through a limited-slip 'posi' rear end with 3.08:1 gears.
The chassis is also different. The frame for the 9C1 Caprice (and the derivative Impala SS) is made from a thicker gauge of steel than the civilian Caprice. In addition, body/frame bushings are present at all 14 body/frame mounting points (on the civilian Caprice and Impala SS, GM left out three pairs of bushings), resulting in less body roll. The springs are also much stiffer, as are the stock Bilstein shocks. You can't see them through the steel wheels, but there are disc brakes at all four corners of the car, with the front calipers wearing thicker pads than the civilian Caprice and Impala SS. You can, however, see the beefy rear anti-sway bar hanging below the rear axle.
The 9C1 wears steel wheels since because of the rear disc brakes, standard Caprice rims will not fit the rear axle. (The Impala SS copes by going to alloy 17" rims.) The strength of the steel wheels, though, combined with the stiff suspension, LT1 power, and heavy-duty cooling, give the 9C1 a towing capacity of 5000 pounds. (Because of the softer suspension and alloy rims, the Impala is rated at 2000 pounds, though many Impala owners swap rims with the 9C1 units and tow much heavier loads.)
The interior bears some differences too.
Law enforcement agencies had a fair amount of variety in selecting interior packages, and I got what is probably pretty representative of the common selections. The front bucket seats are made with heavier cloth and thicker foam to hold up better to wear, and with armor plate in the backs to prevent occupants from being stabbed. The rear bench seat, though is vinyl, and the floor is covered in black rubber in lieu of carpet. In addition to the stock dome light, there's also a 'ticket-writing' light located up front. There's a switch on the dash to turn off the dash lights.
Speaking of interior lights, the cars ship with the dome light disabled at the door switches. The rear door linkages also ship in a state of incompleteness, and the window switches aren't hooked up at all.
The passenger seat also sits on a factory bracket which offsets it to the right just enough for an aftermarket police console to fit in between the front seats.
All this adds up to a pretty quick car for its size. In stock form, I've run a best (uncorrected) 1/4 mile time of 15.875@87.75 mph (with a cracked flexplate, shot torque converter, and dirty air cleaner!). Keep in mind that this is a 4200+ lb. beast running in 95-degree temperatures at a 3800' Ft.
All of this for 3000-4000$
