: 83 Coupe Deville.. To buy or not to buy? Gem or huge headache?

08-19-07, 09:18 PM
Hello. I've been the proud owner of several Cadillacs. Currently, my daily driver is a 1998 SLS that just turned 87K miles, and I like the car very much, despite its many Cadillacisms.

I was formerly an Oldsmobile guy. I currently have an 84 98 Regency Coupe. I dumped the 307 and put in a nice 350 Rocket that runs like new, as it should with only 5000 miles since I installed it. I really enjoy that car, but it would require a lot of work to fully restore. Its a solid as a rock PA car, no rust, but several dents, some bondo, and would need some interior work. It also has 268,000 miles. (yes, the 307 DID make it to 263,000!!!!!)

I have an opportunity to pick up an 83 SDV. It's a Bluish Grey color, with a dark blue interior. This car is in REALLY amazing condition, no rust anywhere, underneath still shows the original undercoating.

All of the accessories work, the AC even works.

Issues include needing an exhaust, and the headliner is sagging. It could also use a paint job. Mileage is 84K miles.

This is an Upstate NY car that clearly made a trip to Florida every year while it was in use. It was repainted at some point. There is no evidence of accident damage or bondo ANYWHERE on the car, but the paint is faded on the roof and hood. The chrome shines like new from every angle, even underneath the bumpers. No dings, dents, scratches.. its kind of strange for such an old car, especially one that hasnt been restored. It's a one owner car.

The car itself is a gem. But my question becomes that HT4100 underneath the hood. That thing is clearly a heap of you know what. It goes up to 60 ok, but it doesnt have any kind of passing grunt, and I'd fear its abilities on a hill.

I do have the 98 to rob for parts, including its engine, trans, and everything else. I'm pretty sure the olds 98 is the same basic car, they even look a lot alike. I hate to take apart my olds, but the Caddy is in much better shape, and I hate doing body work.

But how good, or bad, is the HT4100? It seems awfuly small for such a large car.

There is no evidence of oil seepage, and its clear that the engine hasnt been washed. So that is a good sign. I would like to think the car would be useful with the original engine for some time, at least... I guess it might get ok fuel economy?

This one is not far from being a show winner as is, it's THAT nice. The leather seats look like they have not even been sat in, and even the armrests on the doors havent cracked. All the plastics are supple, even the rear fillers by the tail lights are still flexible, the correct color, and not cracked!!!

With a paint job and a new headliner, the car would look brand new. It still smells new. I've carefully checked it over, and it looks good, I just hate the thought of having to dump a new engine into it next week.

I'm interested in any suggestions before I dip into my wallet.

Thanks in advance!

Aaron K

08-19-07, 09:37 PM

i also wonder how the ht4100 runs. sluggish?

08-19-07, 09:47 PM
I'll try to get pics. It runs fine. As fine as such a wimpy motor can run. It gets up and goes OK, but not like my 350 in the olds. I'm pondering that 350.... that mated up with the 3.41 or whatever gears are behind the 4100 should be scary... and gas guzzling...

Another thought. I know they used thed HT4100 in FWD cadillacs... It would shock me to know that maybe the 4.9 would adapt to RWD?!!???

THAT would be awesome. I loved the 4.9 in my 93 sixty special. Doubtful though, I'm assuming they changed the bolt pattern for the FWD 4100s. Its a happy thought though.

But to answer your question, with a few new hoses the 4100 would run well. It started fine, and ran without stalling.


08-19-07, 10:04 PM
Did you see this one, is it near you?

http://cgi.ebay.com/ebaymotors/83-Caddy-2-door-De-Ville-113k-4-1L-V8-lthr-NICE-No-Res_W0QQitemZ150151899995QQcmdZViewItem?hash=item1 50151899995

08-20-07, 09:10 PM
That one is about 1.5 hours away from here. Not bad, but the one I am looking at is in overall better condition (no dents, perfect leather).


08-20-07, 09:43 PM
Best thing about the 4100 is that most drivers almost never get a speeding ticket.

08-20-07, 10:49 PM
I would still get a ticket. For forgetting to turn on my hazard flashers for going less than 40 up a hill on the interstate.

08-22-07, 05:17 AM
Best thing about the 4100 is that most drivers almost never get a speeding ticket.

is it that much of a slug with that lac body around it?

08-22-07, 06:46 PM
About two years ago, I test-drove an 85 Fleetwood Brougham with a 4100, and was afraid I might not be able to pass a bicyclist.

I've gotten the owner down to a reasonable price, and after a test drive tomorrow, I am going to likely end up driving it home.


Jonas McFeely
08-23-07, 02:34 AM
Ok. Call my HT4100 a freak, but she will GO.

I have driven FAST cars, '05 GTO, '03 Z06, '05 SL500. I know what a truly fast car is. The HT4100 has a horrible wrap, and i understand, but its really not that bad.

Dont get me wrong, i want to swap her for something better, but she really isnt that bad.

I got mine with 43k, it just hit 78k tonight. Performs beautifully. Never any hiccups. The tranny is a different story. But the HT4100 by itself has never given me shit.

As for highways, it will get up and go above 60mph. I drive on I4 everyday to work, so it is on the freeway everyday, never had a problem passing anyone. It will get up above 80mph with no problem, and i made the needle disappear. Had to have at least been going a 100mph+.

HT4100 isnt that bad. Explore her, open her up, take her to the limit. Its better than you think. Though i still recommend you swap it out, like i will do eventually.


08-23-07, 07:31 AM
If the car is in the good shape that you described, I think it's worth getting. Mechanicals are actually the easiest to fix/swap, it's when you get a rusted hulk with bad interior that the $$ will skyrocket. Plus, if the HT4100 runs decently, then you are buying time as well to think about what to do about it.