1979 Cadillac Brougham

[Barry Wheeler #2189]

My wife and I just got back from a 10 day trip to Richmond, VA and back to NW IN. Just over 1500 miles round trip in my just purchased 1979 Brougham. Quieter than our "new" 2003 Olds van. The only problem with the "quiet" was that I could hear the gas guzzling through the carb. Only got 13 MPG, but that was running interstate speeds. No trouble going up the mountains generally, but it was getting a little tired going up Sandstone in WV on I-64W. That is a steady five mile, no break climb that tops out at 2700 feet. But we were still going 55 at the top without a drop-down into a lower gear. It should do slightly better out on the prairie going to Des Moine.

[Porter 21919]

Barry,

Nice ride, you cant even buy a car like that today. With what you paid for it dont worry about the gas.

I used to get 12 mpg around town and 17mpg @ 70 mph highway with my 66 CDV back in 89/90. Not too shabby compared to a Chevy Avalanche, etc.

Hopefully I will finish it soon and get it back on the road.

Porter

[George Woodford clc21025]

The mileage should be somewhat better than 13 mpg.  I have a 1978 Fleetwood Brougham, but I have not checked the mileage.  I dont drive it very much, but the gasoline usage appears to be reasonable for this car.  My 1983 SDV 4.1 HT with 72K miles gave 21 mpg through the mountains (4000 feet elevation) of WV this past May.  You may want to do the basic tune-up check on the car and see whether it improves your mileage.

[JIM CLC # 15000]

06-05-05
Berry, sounds like you are doing pretty-good. A turn-up may help some,how much depends upon its present condition. I had a 1971 Cadillac SDV that got about 8 GPH, regardless of MPH, so, I figured the faster I drove, the better the MPG would be, so, I drove fast most of the time. (MT, no day-time speed limit at the time).
Good Luck, Jim

[Porter 21919]

He is an afficianado of the 472/500/425 engine family, I will let him jump in here. I have a 66 & 67 CDV with factory 429s, both with original engines and they run great, you can see pictures of them at the modified chapter website. We are all CLC members.

If any of you guys are looking for another related forum, visit us at http://www.modifiedcadillac.org/ TARGET=_blank>http://www.modifiedcadillac.org/

Many of us are poor and we rescue old Cadillacs from the crusher, nothing wrong with an updated engine or custom paint, suspension mods, etc. None of us would ever butcher a rare  premium Cadillac or a common one built in mass quantity ,in good shape. We just cant afford  nice mint condition Cadillacs.

When all is said and done we are all afficianados of Cadillac, in any shape or form, the good, the bad and the ugly.

Porter

[Mike #19861]

 The 425 is a very sound engine, one of the best.But, I feel you should get slightly better than 13 MPG overall.

 A good tune up may be in order. Pay close attention to the details here. Make sure the carb is set up properly. Float levels are important in the Q-Jet for driveability and economy. make sure the timing is to spec, and that the vacuum advance is functioning properly. Inspect and be sure the mechanical advance in the distributor is also in good condition. These items are very important, and a scource of many driveability concerns.

 A well tuned 425 should be able to peel rubber at will (even with the 2.24:1 rear gear) and give high teens in the fuel economy area. My parents had a 77 Fleetwood that regularly gave low 20s (imperial) on the highway with power to spare. This in contrast to the 80 368 deVille they had which was a pig on gas and made very little power.

  Mike