1966 Buick Riviera 425ci

General Comments:

I bought my 66 Riviera from a classified ad in my local paper back in 1989. I wasn't looking for one, but when I saw this car I knew I had to have it. I still have the car and can honestly say it's the best car I've ever owned. The 425 nailhead engine was in it's last year of production, but runs very smooth and idles so low, you don't know it's running. The 400 trans has fantastic shifting and that coupled with the posit rear gives all around wicked performance. This car has remained bone stock and considering it's age, it remains a strong and solid car. All I've done since I bought the car is brakes, exhaust, tires and suspension rebuild. GM really put quality and styling into their cars back then as most of the hardware is metal and has held up very well. The engine and trans have not been rebuilt and even though the engine smokes a bit it still has tremendous torque. The 66 and 67 are almost identical except for a few trim changes and the 430 replacing the 425. Parts are difficult due to the uniqueness of the body and interior, but this body style is just as beautiful as the 63-65's. The prices on Rivieras has recently gone crazy due to the Chevy's and Pontiac's having been snatched up by collectors. It's going to be hard to get a decent early to mid 60's Riv at a good price, but if you find one and it's all there, grab it.

Would you buy another car from this manufacturer? Yes

Review Date: 22nd August, 2007

23rd Sep 2009, 09:33

Man, if you are worrying about fuel mileage, then don't even consider buying a classic car. People do not buy these types of cars and sit around worrying about how economical they are, but to answer your questions, 13/16 mpg is the expected range for one properly tuned and driven responsibly.

As for your second question, a good rule of thumb is Pre 1972 you should run a lead additive or do some head work so that you don't have to run lead, and any V-8 engine from 1973 up should be run with premium or 91 octane. Considering that my 1971 Lincoln Mark III with the 460 had a minimum fuel requirement of 99 octane, I part my fuel with airplane grade fuel I get from a friend who works on single engine planes. Works perfectly and I get better economy. Believe it or not, makes no difference to me.

Oh, one more thing, NO ETHANOL, old V-8's don't like that.

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1966 Buick Riviera 425ci

Summary:

Classic GM styling that still looks great

Faults:

Car was mostly original when bought. The only major repair was an oil pump replacement. I believe the engine has never been rebuilt and it does smoke some, particularly at start up.

General Comments:

The 1966 Riviera was and still is a classic beauty. It rides and handles very well. the 425 engine is quite reliable, but is seriously thirsty. The interior is beautifully laid out and the cars are usually optioned with all the bells and whistles.

Would you buy another car from this manufacturer? Yes

Review Date: 25th December, 2004

27th Dec 2004, 10:09

Do you have a 1965 or 1966? it's not clear from your review.

I greatly admire the 1965 model, especially the GS version.

1966 Buick Riviera Coupe 412 cu in OHV

Summary:

Pure Classic Americana!

Faults:

The 412 cubic inch motor had awesome power, but was worn out by time I bought the car. The mileage was only 45000 when it got it.

General Comments:

On the plus side, this big Buick had a pretty good transmission and road handling characteristics. The body was heavy and it sat on a real chassis (frame). No cheap unibody stuff. The 4-speaker AM/FM stereo radio was one of the first true multiplexed models put into a car. The chrome was classy and blended into the body lines well. In 1966, this was a hotrod for upscale, middle-aged folks -- with room for the kids. 0-90 mph in the blink on an eye. Sadly, like most V8 engines of its time, the 412 could not take much more than 50000 miles of city driving before showing its age. It only cost about $700 then for a pro engine rebuild, but that was a lot of money then. $700 could buy you another big, used, American land yacht.

Would you buy another car from this manufacturer? Yes

Review Date: 23rd October, 2002

5th Mar 2005, 16:23

You don't have the right size of the engine for this car-the standard size engine for the Riviera (the only size offered, actually) for this year was a 425-it is likely the engine you purport to have rebuilt in the Rivi wasn't the original engine. Also, unless an engine gets VERY poor upkeep, or is abused, or has a particular design flaw, none should need rebuilding at 50,000 miles.

The 425 Nailhead engine from this Riviera would last forever if kept properly.

In reply to 5th Mar 2005, 16:23

11th Dec 2011, 22:03

I agree with the previous comment... The 425 cu in was the only engine offered. It was a hot rod.. 150 mph speedo. I disconnected the secondaries in the carb. It breezed to 100 pretty quick on the small primaries; was just curious to see what she would do.

The worst hazard was using low test or too low an octane... pinging or even silent pinging on this dome pistoned, high comp. engine would damage pistons or the bottom end. Octane and timing is critical.

The running gear on this car was neat. Adjustable cavitation of the differential and other sway bars and control arms, always drew a crowd while on a hoist.

GH.

In reply to 11th Dec 2011, 22:03

18th Nov 2012, 01:22

There was also a 401 V8 offered in this year of production; the reviewer might have accidentally written '412' instead.

+1 and +1 to the above comments though, neither the 401 nor 425 engines, if treated and serviced properly, would EVER need rebuilding after only 45,000 miles.

Hope the original reviewer is still enjoying his/her Buick!