going to buy a Cadillac 500 or 472 not sure the actual cubic inch, but anyways the guy said its out of an early 70's Cadillac. i know in 1970 the 500 and 472's compression ratio was way up and produced a lot more torque and horsepower, but later years suffered tremendously, i wanted to know if there's anyway to spot a difference between the years visually. the motor is 2 hours away and im going up to look at it on saturday. he sent me two pics of the motor and before i go up there and look at the motor i wanted to see if anyone on here knows anything about them. Thanks!
Bump, wish I had more knowledge. There might be some info on the modified Cadillac board or on the MTS page. I don't know what casting numbers you need to look for, but I think mts would have that info. Sorry I can't post links as they are on my computer at home.
i've been told that only the Eldo had the 500. If that is true then it should have a FWD style pan. As far as the year goes there should be casting dates on the block and heads.I am not an expert on Caddies but was also told the best way was to take out the spark plug and turn them over and measure the stroke. Hope this helps.
You can look at the pistons by pulling the heads or looking through the sparkplug hole to see what kind of pistons are in it....you might not be able to tell exactly what pistons are in it through the plug hole but you'll be able to tell if its a peanut dish, flat top round dish etc... That will tell you the compression ratio, pull the pan and check the numbers on the crank to find out if its a 472 or 500....here is a page that will help http://www.cad500parts.com/catalog/page2.htm also don't pass up the later motors... the method motor companies used to rate horsepower changed in 72, or 73 and they went from a theoretical no accessories no exhaust power at the crank rating to ..actuall with accessories and exhuast. and maybe even at the rear wheel...(not sure about that last part)...but anyway the early numbers are not really quite accurate...so power loss isnt that much through the years. Also power drops due to compression ratio is like 4 percent from 7 to 8 and only like 1 percent from 9 to 10...It matters on the dragstrip not sure so much on the street. Also if its an early 1970 motor running 10.5/1 compression you may not be happy with the way it runs on pump gas...the later ones will run on 87..and the horsepower loss is not as much as you think especially if your gonna do a cam and headers etc anyway...just a thought Jay
Yup, the big reason all engines lost 30% of their power in 1972 was the change from "gross" to "net" HP numbers. The drop in compression happened in 1971. (Eldorado not shown in this chart)
That is probably a 472 with the front sump pan and the point type distributor. No slouch in the power department though. I got a 500 out of a 75/76 Ambulance from my buddy for my 71 GMC because I wanted to be comfortable on the crap gas we have now and still have plenty of towing power. I had a 76 400 in my 82 Cad Deville coupe for a while and it pulled harder on acceleration than any car I have ever owned including the 48, my T bucket and the 69 Cutlass with a 4 speed I had. Tuned right and in the right body those engines run without a lot of extra tweeking.
472 or 500, hi-comp or low-comp, they will still pull a house off of its foundation...if you can get it to hook up... .
I was going to say that my '72 Eldo had a 472 and it would roast the tires at will. Granted I would have liked to have had the earlier engine but it was more than enough engine to pull that big ol pig around. I gave the engine to a kid with a '74 monte because he didn't have any cash and needed to get to and from work and it was one hell of a lot of engine in the monte also.
73RR were you up here at Lewis or out in GA? (sorry to go off topic but you'll get a bump out of it..)
Appears to be an early 472 as previously mentioned. It also has a non-EGR intake manifold and solid flex plate. You are looking at a $200 engine right there...... JB 472
Yeah seems about right...if your set on a 500 check the crank anyway you could order 500 rear drive cars, or it may have been rebuilt and switched around in the past 40 years as well.
Pull a valve cover and run the numbers off the head. That's alot easier than goin inside the engine. The weakest 472 was the 1974 and that was the head design, huge chambers and small valves, BUT they still had lots of power
Amen to that brother! Add 7.50x16 bias plys on a 2,000 lb. car, and have fun! It's certainly worth a 2 hr. drive. Brian
68-71 based on the "2 line" fuel pump. Starting in '72, they were 3 line. Front sump oil pan indicates it's a RWD 472.
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