An Impala is a Caprice with the WX3 option(trim, wheels, leather, lower springs and all Impalas got the LT1) engines are identical as are the trannies, the SS got rear discs though a civi Lt1 Caprice got drums. The SS is in demand because of the look, and somewhat low production numbers.
They stopped building Impalas in 96 because the whole GM fullsize rearwheel drive lineup was canceled.

A 2001 Implala cost less because it is just a run of the mill FWD family car, not a bad car but it is a far cry from a large V8 powered beast like the 94-96.

Selling a LT1 Caprice to buy a LT1 Impala will get you no real performance benifit the only reason to consider this is if you want the resale or you really like the look better.

 

Actually, since the Impala SS was equipped from the fatory with Z-rated tires, the PCM programming limits the top speed to 154 MPH, the civilian Caprice (also with an LT1) is limited to 108 MPH. Besides the brakes, the Impala SS was also equipped with a heavier duty frame, so the differences aren't just cosmetic.

 

9C1 is even more beefed up.

It's been a while since I've read Mueller's FAQ and I don't even remember where it is, but it basically breaks down like this:

1) The 9C1 & the Impala SS are both a step above the standard Caprice.

2) Performance wise, both the 9C1 & the Impala SS are top speed limited by wind resistance to about 140mph, although I believe that in both cases the speed limiter is actually set higher because both cars had high speed rated tires.

3) The Impala has it over the 9C1 in the looks department, no questions asked. It has a nice interior, 17" wheels and a beautiful paint job.

4) The 9C1 has the advantage in mechanical issues. As a for instance, the 9C1 has Oil, Tranny and PS fluid coolers. It also has transmission programming that lets you romp on the pedal at higher speeds and have it stay in 4th to get the higher speeds. AL the body mounts were installed. Lots of little things like that.


Now, the 9C1 isn't collectable in the same way the SS is, although it will probably become more collectable and desireable in the years to come because very few will survive their lives as service vehicles.

On the other hand, if you're going to hot rod a car and really go apesh¡t with it, maybe it would be better to use a 9C1 and let an SS stay closer to original.

Sort of how my generation would cut up Malibus and Tempests and leave the Chevelle SS's & GTO's alone.

 

All Impala SS had LT1 350.

Many reasons the car has a following, aesthetics are probably the biggest part, since performancewise the Caprice is almost there and sometime already there. When I told my mother what I had spent 17k on(43k in 2000)"You know ma, like the Caprice." she was like, "That suppository car?" When she saw it though, "That looks GOOD!"

9C1's top speed is limited according to the factory tires, highest rating was 147. Impala's 154 is due to the driveshaft's 156 critical speed.(Something to keep in mind when running 3.42s/3.73s with a stock shaft...)

Transmission stays in 4th at WOT(above 118) for the Impala also.

As above though, don't buy an Impala for the performance advantages, it's just not cost effective, you can put your Caprice far above a stock Impala in that department, for the price of the Impala. Even the image can be achieved and even surpassed. I've seen some Caprices that were not clones that still made me say, "Wow!"

I still think a full-on Caprice Wagon SS clone is the best looking B-Body ever. (Shaved rack, radiused wheel wells,...

 

Originally posted by Wayne Bengston:
9C1's top speed is limited according to the factory tires, highest rating was 147. Impala's 154 is due to the driveshaft's 156 critical speed.(Something to keep in mind when running 3.42s/3.73s with a stock shaft...)

Can you go into more detail on the driveshaft issue?

 

All driveshafts have an RPM at which they are no longer safe, this is independent of balancing and is related to the length and diameter of the shaft, sidewall thickness, material,... For the stock Impala SS/9C1 shaft, it is 6000 RPM. This coresponds to 156 with 3.08s, 141 with 3.42s, 129 with 3.73s, 118 with 4.10s and 106 with 4.56 all with 27" tires(255/50/17) One side effect of gears is the fact that it is easier to achieve these critical speeds.(It's very easy to hit 129 with 3.73s...)

This is not to say that you won't have problems at lower speeds or that you will have problems at higher speeds, just that above 6000 RPM, there is the distinct possibility of sudden and catostrophic failure.

 

WHAT YEAR N COLOR

 

Keep in mind: there's no such thing as an 'Interceptor' engine. The only difference between the LT1s in a Caprice, Impala SS, Roadmaster, or Fleetwood, was the silicone hoses on the 9C1s. Within factory tolerances, and accounting for owner maintenance, these ironhead LT1s are identical.

The trannies themselves, are also indentical, although a 1st gear blockout was added to trannies in 9C1s to prevent the cop from grenading it.

The differences begin from there, but the ImpalaSS has more in common, functionally, with a Caprice 9C1, than with any other B- or D-body.

 

Originally posted by Wayne Bengston:
For the stock Impala SS/9C1 shaft..

That's odd...
I was under the impresion that the 9C1 driveshaft actually was better than the ImpalaSS driveshaft and even had a different part number.
I haven't looked myself, but that's the impression I had.

 

1) The 9C1 & the Impala SS are both a step above the standard Caprice.

Except for the interior

And it's only a small step up

Later,
Bob T.

 

Check out this web site. It lists the differences between the civilian Caprice, 9C1 and Impala SS.

http://impala.homeip.net/impala/faq/faq.cgi#police_overview

 

I pulled out my handy-dandy parts fiche. The drive shafts are listed as follows:

WX3/WX8 = 26047193 = Retail $455.74
9C1 = 7842127 = Retail $502.97

 

Originally posted by EricTheBald:
</font><blockquote>quote:</font><hr />Originally posted by Wayne Bengston:
For the stock Impala SS/9C1 shaft..

That's odd...
I was under the impresion that the 9C1 driveshaft actually was better than the ImpalaSS driveshaft and even had a different part number.
I haven't looked myself, but that's the impression I had. </font>[/QUOTE]Civi units have the lighter duty driveshaft.. All Impala SS's and 9C1's have the SAME driveshaft... Those of you who still have the sticker on it, should see "BB" on the sticker.

The Imps and 9C1's might have had different part #'s for the driveshafts, but they were the same .088" wall with the hardened slipyokes and weld yokes.

DRMAXIM, your Micro fiche appears to be wrong. I have the actual build sheets infront me for those driveshafts. They are as follows:

IMP/9c1 = 26047193
CIVI = 7842127

 

Damn, 160mph in an Impala is actually dangerous on stock driveshaft and rearend ratio? Huh, who would have figured?