1972 Cadillac Engine size question....

James Fischer

PCS Member
Could someone please shed some light on the engine size in 1972 Cadillacs...
.
I WAS under the understanding that MOST Cadillac ambulances had the 500 size motor...but I just recently read that in reality Cadillac did put the 472 in about 50% of that years cars....???

I find that off base,since most of the early '70s Caddilacs I have seen were the 500.....?

Any thoughts ??

Thanks
 
1968 till 1974 all commercial chassis cars from Cadillac had the 472 V-8 across the board, including Fleetwood and DeVille models as well. I think the Eldorado's of the early 1970's did have the 500 CID engines. For 75 and 76 DeVille's, Fleetwood's, Commercial Chassis and Eldorado's all had the 500 CID engine. If your 72 has the 500 more than likely it was swapped at one time, as it would "bolt right in" the place of a 472.
 
Good question. Cadillacs from 1968 thru 1974 used the 472, except the Elderado which started using the 500 in 1970. The 500 was not used in the other Cadillacs until 1975. (info from Standard catalog of Cadillac).
As far as I know only 472s were in the commercial chassis.

So here is another question, since the 500 was avalible in 1970 could you get your commercial cahssis ordered with it?
 
1968 till 1974 all commercial chassis cars from Cadillac had the 472 V-8 across the board, including Fleetwood and DeVille models as well. I think the Eldorado's of the early 1970's did have the 500 CID engines. For 75 and 76 DeVille's, Fleetwood's, Commercial Chassis and Eldorado's all had the 500 CID engine. If your 72 has the 500 more than likely it was swapped at one time, as it would "bolt right in" the place of a 472.

Sorry Jeremy, Im not trying to one up your post, but when I began to look it up and type it there was no reply.
 
Agreed

Hi James,

Both John and Jeremy are correct. I've run into so many situations in my years buying Cadillacs from people that just aren't familiar with them, that they refer to just about anything over 400ci as the "500" or the "502", when in reality it's almost always a 472. The 472 is by far my favorite Cadillac engine....the older ones starting in 1968 had 375 hp stock with 525 foot lbs of torque. Great compression as well....if I remember correctly 10 1/4:1
 
"So here is another question, since the 500 was avalible in 1970 could you get your commercial cahssis ordered with it?"


Well, I don't like to use the words "always" and "never" when it comes to professional cars; about the time you swear something was or wasn't, the rare exception comes along to prove otherwise.

As far as I've ever known, 1970-74 Cadillac commercial chassis were only offered with the 472 engine. IF a customer asked about an optional 500 engine, they would likely have been told it wasn't available in the commercial chassis line. Of course, there could have been the one exception where somebody just HAD TO HAVE the larger engine and was willing to pay for it at any cost. In this case, I strongly suspect a post-delivery engine swap would have taken place, though I've never heard of such a thing happening around here.

I agree with the positive comments about 472 engines. I've had extremely good luck with the many I've owned. People are always impressed when they find out our '75 Lifeliner has a 500 engine, but by 1975 GM had it so choked off with the emissions garbage, the performance is anything but impressive.
 
Engine size

Tony I know exactly what you mean by impressing people, when talking engine size. The guys with engines anything 6 liter or under, are fun to approach and talk about cars with. You tell them you got a 7.7 liter under the hood of your vehicle. They get that funny stare back at you. Moments I will always cherish. And you tell them what you drive and its another of those funny looks at you.
 
so tell me is the 74 a unleaded fuel engine. I know that the 73 was not though it was in the standard caddy's. I'm guessing they did not go unleaded fuel till the 75 76 years.

now then the 58 we have here has the 390 not the 383. as does the 63. though they are different engines they are the same cubic inches.
 
383?

so tell me is the 74 a unleaded fuel engine. I know that the 73 was not though it was in the standard caddy's. I'm guessing they did not go unleaded fuel till the 75 76 years.

now then the 58 we have here has the 390 not the 383. as does the 63. though they are different engines they are the same cubic inches.

Your 58 has a 390? I thought those had the 365? I know that was so close to the 390 change for Cadillac so I had to ask. Is it the original motor?
 
Your 58 has a 390? I thought those had the 365? I know that was so close to the 390 change for Cadillac so I had to ask. Is it the original motor?

The 58 should have a 365. Cadillac used the 365 from 1956 through 58. From 1959 through 1963 the 390 was used. (Again going by my Cadillac book).
 
but what does there book say was in the CC. the numbers don't lie it's a first generation distributor in the back 390. with the 4 speed jet-away auto. could it have been change? I guess it could have. you got anyway to check the number?
 
but what does there book say was in the CC. the numbers don't lie it's a first generation distributor in the back 390. with the 4 speed jet-away auto. could it have been change? I guess it could have. you got anyway to check the number?

All the book says about the commercial chassis this year is the wheelbase. number produced, model number and body style number. The engine info gives the specs (horsepower, displacement, bore, stroke carb and model number of carb. (If you want this info I have it) For trans it just says hydra matic.
It says in the book serial numbers match and are located on the center left hand side of the block above the oil pan, and at the front of the left handed frame side bar. Serial numbers now use a 3 symbol prefix The first pair numeric symbols designated model year. A one letter alphibetical code indicates model and series. Each prefix was followed by the consecutive unit number, which started at 000001 and up. If you give me three symbol prefix I can see what the book says as model. The commercial chassis may not have the Alphibetical number after the year, but must match frame.

Hope this may help some. The book is a great source, it gives so many details, including options and cost of them, price of car when new etc. I remember using the book to fight a seatbelt ticket, and won.
 
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this is the part of these cars that is so frustrating. I swear that Gm either used up hold over stuff or experimentation with new on there Commercial chassis. they never hold true to the standard caddy for the year.
I know this engine is a 390 as we had to replace a valve in it. the numbers off the engine and the eureka tag (the tag is loose) and the paper works from Illinois match. however any state that has had 3 of the last 4 governors jailed for improprieties while governor? there paper work might be highly suspect. we can and will get it down enough to see if the frame numbers are the same. but as we all ready Know with at least the MM they would pull the cowl off when the chassis came in and they just grab any one for the next car in line. engines were swaped from one chassis to another in assmebly. so haveing a matching number engine and frame is a rairity and it it matches the body tag it's stranger yet. with a miller that is.
 

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Here is a specifications chart I found online for the 1968-1975 472 Cadillac engines.
All info is for 4BBL cars. EFI Info has been removed.

Year Disp. Fuel Horsepower Torque@RPM Bore x Stroke Comp. ratio
1968-'69........ 472 4bbl 375@4400 525@3000 4.300x4.060 10.5-1
1970............. 472 4bbl 375@4400 525@3000 4.300x4.060 10.0-1
1970............. 500 4bbl 400@4400 550@3000 4.300x4.304 10.0-1
1971............. 472 4bbl 375@4400 525@3000 4.300x4.060 8.8-1
1971............. 500 4bbl 365@4400 535@2800 4.300x4.304 8.5-1
1972-'73........ 472 4bbl 220@4000 365@2400 4.300x4.060 8.5-1
1972-'73........ 500 4bbl 235@3800 385@2400 4.300x4.304 8.5-1
1974............. 472 4bbl 220@4000 365@2400 4.300x4.060 8.25-1
1974-'75........ 500 4bbl 210@3600 380@2000 4.300x4.304 8.25-1
1976............. 500 4bbl 190@3600 360@2000 4.300x4.304 8.5-1
 
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this is the part of these cars that is so frustrating. I swear that Gm either used up hold over stuff or experimentation with new on there Commercial chassis. they never hold true to the standard caddy for the year.
I know this engine is a 390 as we had to replace a valve in it. the numbers off the engine and the eureka tag (the tag is loose) and the paper works from Illinois match. however any state that has had 3 of the last 4 governors jailed for improprieties while governor? there paper work might be highly suspect. we can and will get it down enough to see if the frame numbers are the same. but as we all ready Know with at least the MM they would pull the cowl off when the chassis came in and they just grab any one for the next car in line. engines were swaped from one chassis to another in assmebly. so haveing a matching number engine and frame is a rairity and it it matches the body tag it's stranger yet. with a miller that is.

That is strange. It has no mention of a 390 even avalible in 58. The engine number is on a strange place too, by the book it says in the location I previous mentioned.
Just for the hell of it, what brand and model number is on the carb. I can look that up and see what it comes up with.
Is there any chance the valve you replaced is the same for a 390 and 365.
I dont want you to think Im saying you are wrong on the engine, im just going by what the book says. Who knows it may be wrong.
 
they had a real head scracher comming up with the right valve. thats when he told me it was a 390. I'll check the carb tag tomorrow.
 
the number on the carb tag is 7012010 the box for the kit has 365 had written on it.

The mystery still remains. i looked in the book from the 331ci through the 365 and 390s, and this number is not listed as any of the options. There is a few in the 365 range that were close but no cigar.
Sorry to be less than helpful.
 
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