The Stovebolt Site Forums The Shop Area The HiPo Shop 512 caddy motor

wat kinda power could i get out of one. an would this b a good power plant for my 64 chevy truck.

yes it would be a great engine for your truck.
and you have a 500 hp torque pig at a resonable cost. but if you want more it will be more exspensive than for example a chevy bb.
you can read more @ www.cadillacpower.com - great forum.
i have a -71 500 in my 56 chevy truck and it pulls great. the only problem is that the engine is a bit longer than a chevy sb and it is a problem to use a real good working cooling fan. but i am working on it.
-anders
my 500" chevy truck

I small piece of advice. Get the good insulation for the firewall & floorboard area of the cab. Otherwise, your dash may feel like a pizza oven. When I say good I mean a product like 'Dynamat'. It's pricy but worth it when you get big blocks like chevys, nailheads, 455 rockets, etc. close to the fire wall. Another problem is the heat behind the dash makes the A/C hoses sweat and water will drip on your sweetheart's feet, and OH BOY, 'been there/done that'.

Anders;
I know this probably isn't something you get too concerned about,but what does an engine that size do to your fuel economy? I'm building a '74 Chevy one ton long wheelbase flatbed duallie for a work truck,and am trying to decide on an engine that can be reasonably good on gas,and still have lots of torque and power. It'll be running empty some of the time but will be pulling a loaded car trailer and loads of steel for 300 miles often. I have a 355 for it now,but I don't think I can pull enough power from it to do what I need to do. I'm not seriously considering a Diesel for it because of the cost of purchase and installation. So I'm wondering if a big Caddy or Olds can be set up to get some decent mileage in a truck this size.
Speed

you do not buy Cadillacs for fuel mileage, at least not in the late 60's and early 70's.

That cadillac power forum is full of lots of great information in old posts and the posters are very friendly.

-W

Speed-
Give some thought to a 6 speed tranny. With 2 overdrive ratios available you can run a really low gear in the Rear End and still get Highway speeds you can live with...

If you're going to be doing alot of pulling, you might consider a Deisel instead of a gas engine. Better economy, especially under a load.

My experience with the fuel milage on small block versus big block in the same vehicle with the same transmission ratios and rear end ratios is with Ford 360 and 460 engines, but should be the same with a SBC and BBC. I got exactly the same milage when I drove them the same, but would get significantly fewer MPG when I used the power available with the BBF. Pulling a loaded six horse gooseneck over the Grapevine, I could go 70 MPH with throttle to spare, whereas the 360 could do about 40 full out. Trade off was 2-3 MPG with the BBF while doing so. If I had slowed to 40, I think it might have gotten better milage than the SBF.

There is some physics and ratio optimization that determine fuel economy. If both motors are big enough and designed with the same attention to efficiency for the job at hand and are coupled to appropriate transmissions, rear axles and tires, I think its reasonable to expect the smaller one will get better mileage.

Most cases where you hear a bigger motor got better mileage it really means the smaller motor was not really up to the job.

Based on what he said in another thread I don't think mileage is really something our young rebel friend is concerned about.

Unless you plan to spend serious money modifying either motor the 500 Cad (bored to 512) is going to make more usuable power than most other stock gas motors you'd find used for similar money. Of course there are motors out there that will outperform the Cadillac but not that you are likely to find cheap.

If cheap power is not important, start with something with more performance parts support. Once you start buying performance parts for the Cadillac you're going to wish you had a big block Chevy instead...

Do keep in mind that the stock Caddy intake is a low rise type, due to the low hoodlines of the cars it was installed in. They're not real good for high RPM usage as they dont breath well at the higher RPM band. There are aftermarket solutions to that, though.

well gas mileage dont really mater b/c im not going to drive it much mostly to shows an up an down the bolavard im jus looking at wats out there an trying to find the best hp for the money like in my other post about the 383 an vetes if i can build a truck in the 10,000-15,000 dallor range keep in mind i have people so to speak an stay within 2 car lentghs of a whats the price on a new vette? then facter in the weight i guess that would be sucees i want to have it finshed b4 my 15 bday

Reb-
Just being nosey, how much is the Caddy motor going to set you back?
Seems like you are on to a really good idea, but like OldSub is saying - comparing to the venerable 454 Big Block is an important consideration...

speed 6351 - sorry, i do not know about the milage. i have not run my truck that much yet. i use 3:08 rearend so i do not think it is too economic with the gas. but if you have the engine in almost stock condition and use 2:75 or 2:56 i think it would be fairly good. and there is some overdrive solutions you could use.
by the way, i should be concerned about the milage, here in sweden the gas price is about 50% higher.

64CHEVYREBEL - as i said if you want more than 500 hp go with the chevy bb. if you want to be different use a big cad and get a lots of low rpm torque.
/anders

In my neighborhood a base model new 'vette is nearly $50,000 and a loaded Z06 is past $70,000. The LS7 motor that powers that Z06 is nearly $15,000 as a crate motor.

I like the 500 Caddy and would say its the best option under SOME circumstances. If I had $15K to spend it may not be my first choice but then it would really depend on what else I had to fit into my budget.

With that much cash to spend on a motor for a fast pickup I'd be thinking about a BBC 572 or 640. If you have to buy a transmission too, a built 4L80 is two to three thousand or more which would eliminate some of the motor options.

If your budget is for the entire vehicle including wheels and tires and rear axle, I'd put more of that money into hooking the power to the ground and buy a motor like the Caddy. With the right suspension, wheels and tires, a stock Cad motor is going to be pretty fast stop light to stop light.

Maybe not the way to approach a quarter mile racer, but real fast for short sprints. If I had $15,000 to spend on a stop light racer I'd probably buy a C5 'vette, but if you haven't already figured it out, I am a Corvette fan and drive one almost every day.

im hopeing to come in under 10 grand complete truck now later on done the road when im on my on or have more of my on money im goning to go all out in the drive tran.and the 512 is $1500 but i can get a 454 an turbo 400 for bout $1000 from a buddy but it doesent have any power it came out of a suburban its goning to be a mean truck it might not ever go to the drag strip but idc

wat about a cam for a caddy a rough idle is a most

The 572 isn't exactly cost effective if you're on a buget. The basic engine, with a Demon carb and ignition, runs around $13500 from Summit and Jegs. GM might be a little less, but won't include the carb. That's for the 620 horse version. For the 572R (720 horse) you're looking at around $18000+. That's just for the engine. Stacey David has one (the first one actually) in Copperhead, backed up with a seriosly modded TH400 w/Gear Vendors o/d. It also has a 300 horse nitrous system. So far, he hasn't been able to get it to hook up. And that's without the N2O.
The Cad engine would be a good one to start with, especially if you're looking for big displacement, but be prepared to do some mods to it to get the higher rpm out of it. Namely in the intake side.
While the Cad would be unusual, a BBC would be easier/cheaper to build up. They also breath better and have a better aftermarket support.

cant i get a 632 900hp for a little more then a 572 720hp now what kinda hp an tq can i get stock out of a 512 caddy with mayb a intake carb an cam change?

Baldy;
With the loads I keep ending up having to move,I thought a big block,Caddy or Chevy,might not have to work as hard,and that might result in better mileage,but the more I look at it,I'd probably be working a smallblock OR a bigblock equally hard,and smallblock parts are a lot less costly. I think you've hit it,though-my 355 just isn't enough to do what I'm asking it to do as it is. I might have to look into a few changes;my gearing,maybe a different cam,and I will be running headers in my next truck,Mad Max.
Tractor78;
Tell me more about that six speed;where can I find one? Will it bolt to a Chevy bellhousing or directly to a Chevy engine? What trucks do they come in?
Speed