What do you know about Cadillac 500's

[72' Jimmy]

I have option of buying a 500 out of a cadillac for a few hundred dollars. I don't much about these motors just that they got decent gas milage for a big block. I was thinking of putting it in my Jimmy. Do you think that it is worth rebuilding the 500 or looking for a 454?

[LUV2XCLR8]

Longhorn Man is the only Caddy guy I know, try PM's him

[brian26]

I know a few things.

I liked the '71-'73 472-500 engines the best. The most power on todays gas.

Oddly, the worn out 472 seemed stronger than the rebuilt 500.

A few things to consider-
1. Hopefully you're using an automatic since there is not a pilot hole for a standard. You'll need a BOP plate to adapt the Chevy trans to it.

2. use the right thermostat
3. You'll need a new motor mountig setup. Don't know if there is a bolt-on but it's possible.
4 Might have an issue with the left side exhaust not clearing the steering box. Headers may be a good direction.

5. 4 core radiator
6 I get 12 mpg, could be better but it's fine for what I do.

7- You'll need an Eldorado rear sump pan and pickup most likely.

[Jtrux]

I worked at a machine shop where we rebuilt a couple, one was a 73 I believe and the other a 75. One was bone stock but ran like a bear and the other had ported heads, decent cam (it's been a while so i'm not sure which one), Edelbrock intake and the stock quadrajet. It was very impressive and would out run a lot of cars and trucks.

The thing about the standard tranny is true but you can do it one of two ways.

1. cut off the end of the main shaft on the tranny and just run it like that

2. have the crank machined for a pilot bushing

There are aftermarket companies that make all kinds of performance parts for these engines including bellhousings, clutch kits, etc. etc.

[tcb-1]

second the Andy (Longhorn Man).

[vtblazer]

Board member grendel has experience with these, contact him.

[Huck]

Interesting, you wonder about a 500 cubic inch Cadi and in the same sentance ask about gas mileage---on a 4x4?----HELLO!

[72' Jimmy]

I Had a buddy that got 14-15 MPG in his Cadillac. I think that I might have the option of getting a 472 also. I think that the 472's are more commen. parts might be cheaper. I will have to look into it.

[brian26]

I'd go personally with the 472. Yeah I know-more cubes= more power. But my worn out '73 472 launched a lot better than my rebuilt 500. That 500 was rebuilt by a very reputable builder in this area,it was a stock redo but yet should have been more impresive.

FUEL MILEAGE? Right now our gas here is $1.75, adjusted for inflation that's about $.70 in 1981 dollars. $3 was the same as $1.27 or thereabouts.

Should you go with a Caddy, keep in mind an automatic is the easiest to adapt to. There are more options out there now than when I was putting one in my '60 Caddy. Never have regretted it. I wouldn't have used a 700r4 had I known everything I do now.

[brian26]

Just remember they put out a lot of heat too. Keep that starter coool enough. I would think about a vent much like the vents on the '70s Tran-Ams-behind the wheelwell, in front of the door.

I did find the Tilton ministarter to be a good one to go with. Still had to mill 1/8" on the mount to get the starter closer to the flywheel. Then you'll have to grind/bevel the starter gear back enough so that it doesn't hit the flywheel.

NEVER USE A 425 PUMP. I DON'T CARE WHAT THEY SAY, I'M NOT DOING THAT AGAIN.