I had a friend approach me today with the idea of running a 472 or 500 ci caddy motor in his jeep and mine. The weight is the same as a 350 sbc if you replace the exh. man. with headers. The web site I went to www.500cid.com has tons of info and the torque and hp cant seem to be beat, so has anyone ran one and could I get some pros and cons from experienced wheelers?Thanks

they are awesome motors but do you really want to get about 5 or 6 mpg out of your jeep? and you have to sit back and wonder if you really NEED all that power or if it would be just a novelty. also think about alll the other shiat you would have to beef to deal with it. im thinking TH400, NP205, D60 front, 14 bolt rear. and then youd just be breaking driveshafts.

so yeah, theyre cool, but WHY?

I've seen it done, they have enough power alright, But you will probably have to stick with the TH400 and will need to swap the tail housing/ output shaft to get a t-case on it. That would be one problem. Plus I'm not sure where the oil sump is, if it's in the front of the motor it will probably get in the way. And I think the oil pump might be hanging off the side like a jeep engine. :barf:

I think some guys put the old 472 heads on them for more umphh...

Page 36, March 2002 JP Magazine!!! They do an install in a Flatfender!!!:beer: :) :beer:

Wow thats a good response time. I just posted this. I understand the setup is supposed to get better milage than that. I would not have a problem using that power with a 14bolt and d60 and I have a th400 going in anyway. I was told the bolt pattern is the same as the chevy, not pontiac and olds. The front drive cars came with the rear sump oil pans and if you get the motor with the front pan, the kit is 160.00. If I go with my original plan of a street strip built type 355 sbc with 10to1s, 202s, and a lumpy cam I would get the 5mpg anyway. I want power in this Jeep for dunes and mud. I can detune for trails anyway. The only upgrade I think would be necessary immediately would be an Atlas II. Anyone ran one yet? I am going to the article you mentioned after hitting the reply button, thanks

You will get the same mileage as a carbed 350. It would have tons of smooth torque. I have a 454 in a cj7 and it just plain kicks ass... mud, sand, rocks ...torque is the name of the game.

I have a 460, C-6 205 in my CJ-7. Its niiiiicccceeeee :D

rockhog runs one in his commando. thing is just fawking sweet.

Originally posted by Go Patriots!!!
they are awesome motors but do you really want to get about 5 or 6 mpg out of your jeep? and you have to sit back and wonder if you really NEED all that power or if it would be just a novelty. also think about alll the other shiat you would have to beef to deal with it. im thinking TH400, NP205, D60 front, 14 bolt rear. and then youd just be breaking driveshafts.

so yeah, theyre cool, but WHY?

They don't get 5 mpg more like 10-15 mpg. I had one in my blazer and it got 12-13. This was a stock one with no mods to it at all. I have even heard of people that has got as high as 20 mpg in the Couple De Villes. They will get better mileage than a 454 or 460 and they weigh in at 25lbs more than a Small Block. I fell that they are the best big block every made. My brother and I have built a 529 Caddy that made 649hp at 5600rpms and 660ftlbs at 4400rpms. This is a cast iron headed no aluminum heads here. I would say that is pretty good and yes it does have 12.9-1 compression but it idles at 1000rpms out of gear and 800rpms in gear. I think that we can get 715-725hp out of this motor with a little more head work and one more cam change. Try and do that with a big block chevy on the same cost it cost us to build this engine. Al, at MTS is a great guy and has great prices on parts also.

The bell housing pattern on the caddy is the same as the BOPhowever I believe the buick is the onlu one that has a manual bell housing that will work due to the location of the starter ( driverside). However you would have to get a custom flywheel made to mate the caddy.

I have a '69 472 in my Scout. It is a good motor, but it is high compression, and I have to run Super Unl. or it will ping bad. Rear sump pans can be found in El Dorado's and 1980-81 cads w/ the 368. I'm using a 368 pan on mine. If you want to run a manual tranny, you need a $$$ custom flywheel, and drill the crank for a pilot bushing. I'm using a TH400 and Dana 20 out of a '69 Wagoneer, bolts right up.

I get crappy gas mileage, and I use alot of gas when wheeling. I'd like to find a 425 in good condition and swap that so I can run reg unleaded and get better gas mileage.

Do any of you guys running these have any concerns about the carbueretion...or doesn't your terrain cause any problems.

Dreaming of drivetrains, I have been thinking 500, Th400, OR Doubler.....but the only thing I'm concerned about would be the move away from fuel Injection

All these big Cads had Quadrajets, the next best thing to EFI. A few rare 500's and 425's had analog fuel injection, but I hear it isn't the greatest system.

You could put TBI on one for less than $1000, Projection or Howell-Efi.

A big ole 2bbl rockester with the float lowered works for me... A big gulp of air and Lots of fuel right off idle keeps the big slugs moving at low speed, nice crisp responce. It will run out of fuel at high speed after a minute or so, but by that time I'm ready for a break anyway.

Originally posted by BillaVista
but the only thing I'm concerned about would be the move away from fuel Injection

From what I have been able to gather from some guys on CK5 that like/run the big Caddys, the caddy distributor can be modified for the electronic pickups required by the TBI ECM. Then, you mount the appropriate sensors, get a 454 TBI unit with adapter (fits a common spread-bore (QJet) pattern), harness, ECM, etc. The hardest part (and the only really custom part) is the distributor.

I must admit that a return to basics (carb) has plenty of appeal too.

With my FI 4.5 and electronicly controlled AW$ auto it can get frustrating as heck chasing electrons.

Since I'm asking the right crowd - what sort of, if any, electronics are required for the older autos like TH350 and TH400?

I guess a manual is the ultimate in simple / no electrics, but I understand it can be a bitch fitting one to the 500, and I'm kind of stuck on the auto after I switched.

Most 350/400 trannys don't have anything you would really call "electronics". Electric kick downs and such is about it, and many models don't have any wires at all. Seems like read/heard that some were wired with lockup converters but I'm not sure about that.

As for carbs, I loved my Edel QJet most of the time. However, it only took a few times with it (454 with QJet) sputtering and dying in bad places to convince me to go EFI on this rig. This K30 will be my first attempt at anything that would be considered moderate to hard core, so I figured I sure didn't want to deal with even more of those situations (and likely in worse positions).

So these motors are not the sbc bolt pattern, darn. I have a th400 with a chev pattern and a d20. Ill have to look to see if its a universal. This swap is looking really good to my friends and I. I just like to do alot of research before redirecting my project. Im sure you guys understand.

I agree with everything Donovan said. I know he know's a lot about caddy engines

They ARE B.O.P. bolt patterns, but There are adaptors for them.

The 425 Generally DOESN'T get better gas mileage than it's big brothers. They aren't as powerful as their big brothers either. However I have ran a STOCK 425 and outran "The fastest camaro in town" Some punk RICH kid.

Like I said in the other post "Cliffhanger..." If you have your Caddy 472 or 500 built for torque you DON'T even need a doubler, since you have soo much Low RPM torque. IE: very controllable power.

Caddy engines are defintely the :nuke: :vader2: