What is the difference?

I have an 88 caprice classic and was wondering what the difference was between the regular caprice and the 9c1

9C1 is the GM SEO (special equipment option) for Police Package. Generally, a 9C1 has a strengthened frame, improved suspension, heavy-duty brakes and suspension components, an upgraded electrical system, a more powerful engine and a stronger transmission. Some also have shorter gearing (most 350s have 3.42 gearing, while mine has the "stock" 3.08 gearing). Basically the upgrades it takes to produce a good police car.

For example, the '88 Caprice Classic came with a 305 engine as the most powerful, with the TH200-4R as the 4-speed overdrive automatic.

My '88 9C1 came with a 350 and a TH700-R4 transmission.

I think silicon212 covered it pretty well. Depending on the year, the 9c1 SEO included several options. Here are some of the ones the same for all years of the Caprice 9c1:

*Heavy-duty frame
*Stiffer/stronger suspension components (springs, shocks, lower control arms)
*Front and rear stablizer bars
*Larger radiator
*Green silicon hoses and worm clamps good for the life of the vehicle (these seem to last forever)
*Larger bolt wheels
*Heavy-duty battery
*External engine oil cooler
*Heavy-duty front and rear brakes (another thing better than civie caprice)

The 9c1 also had a larger displacment engine available (350-cid was an option on 9c1 since late '70s; it was unavailable in civie Caprice until 1994 with exception of 1993 LTZ)

Thanks for the responce, good info