What was the best Cadillac engine produced between1970-1979?

I've owned 16 Cadillacs over the years - 1939 up to my 2008 DTS.  My favorite engines were the 472 (which is in my currently owned '70 limo) and the 500 that was in my '75 Sedan DeVille.  Actually, there were no "bad" engines until the 4.1 debuted.  I tell anybody who asks about buying a used Caddy to avoid the 4.1, 4.5 and even the 4.9 motors. There were very few 4.1s that went 50K miles without head gasket issues.  A few more 4.5s made it to 100K.  Probably half of the 4.9s will make it to 100K. In normal Cadillac terms, these are TERRIBLE percentages.  I would also avoid the first year Northstar engines - they developed valve guide wear around 50K.  The newer Northstar engines are great, but a little difficult to work on - a lot of non-dealership mechanics can't even find the starter. The old 365 and 390 motors are very durable.

Bob Woodside 

Everyone loves the 500, but good Lord knows your gas mileage will be 8 mpg. The 472 is a bulletproof motor. I'd be pleased to own it. 

Over the years I've owned, or currently own, 1939 LaSalle, 1953, 1954, 1960, 1963, 1965, 1966, 1967, 1968 and a 1976 with a 1969 engine in it.  The '39 is currently being rebuilt, so I'm excited to get this warhorse back on the road.  My '53 & '54 cars with 331 engines are solid performers, although their displacement is less than the more recent cars.  I've never owned a car with a 365 in it, so I can't comment, although I've heard a few bad things from friends.  Even though I love the styling of the '65, '66, '67, I'll probably never buy one again as in my experience there is a problem with rings that causes blowby.  Typically, the oil vapors start to flow backwards out of the oil filler cap, pooling directly below the cap, and even beginning to stink as you drive down the road and the car is fully heated. 

I owned a 1968 (Superior hearse) for a while, and sold it because of rust problems.  But the 472 engine had 36,000 miles on it and was THE smoothest (older) Cadillac engine I'd ever owned.  Note that starting 1971, 472 compression ratios were changing to accommodate emission standards, and through 1974, in my opinion, the 472 only got weaker.

Hands down, my '76 (S&S hearse) with the '69 engine is the star of the fleet.  It's totally solid, and runs down the road as the proverbial you-know-what ape.  I'll be bringing it this summer from my home in Fort Wayne Indiana to the CLC Nationals in Kansas City.  It's totally road worthy and in a recent trip to New Jersey, didn't miss a beat going there or back.  By the way, the original '76 HEI is installed in this 472 and works great. 

One last thing about the '63.  Even though it's rated as being a 390, it's unique for '63 in that is has alternator and power steering pump positions of the '64-429.  My '63 had oil blowby, as the later '60's cars I mentioned.

I don't have an opinion about the newer Cadillac engines, although what little experience I've had with the 8-6-4 engine of the '80's has not been good.  Tom

Over the years I've owned, or currently own, 1939 LaSalle, 1953, 1954, 1960, 1963, 1965, 1966, 1967, 1968 and a 1976 with a 1969 engine in it.  The '39 is currently being rebuilt, so I'm excited to get this warhorse back on the road.  My '53 & '54 cars with 331 engines are solid performers, although their displacement is less than the more recent cars.  I've never owned a car with a 365 in it, so I can't comment, although I've heard a few bad things from friends.  Even though I love the styling of the '65, '66, '67, I'll probably never buy one again as in my experience there is a problem with rings that causes blowby.  Typically, the oil vapors start to flow backwards out of the oil filler cap, pooling directly below the cap, and even beginning to stink as you drive down the road and the car is fully heated. 

I owned a 1968 (Superior hearse) for a while, and sold it because of rust problems.  But the 472 engine had 36,000 miles on it and was THE smoothest (older) Cadillac engine I'd ever owned.  Note that starting 1971, 472 compression ratios were changing to accommodate emission standards, and through 1974, in my opinion, the 472 only got weaker.

Hands down, my '76 (S&S hearse) with the '69 engine is the star of the fleet.  It's totally solid, and runs down the road as the proverbial you-know-what ape.  I'll be bringing it this summer from my home in Fort Wayne Indiana to the CLC Nationals in Kansas City.  It's totally road worthy and in a recent trip to New Jersey, didn't miss a beat going there or back.  By the way, the original '76 HEI is installed in this 472 and works great. 

One last thing about the '63.  Even though it's rated as being a 390, it's unique for '63 in that is has alternator and power steering pump positions of the '64-429.  My '63 had oil blowby, as the later '60's cars I mentioned.

I don't have an opinion about the newer Cadillac engines, although what little experience I've had with the 8-6-4 engine of the '80's has not been good.  Tom