I got this posted in general too. I got a 68 caddy 472 I was thining of using for a buggy. I've never used these caddy motors before and I'm kinda luimited on knowledge of weakness'. I've rad the valve springs are soft and that the con rods are weak. I'm building for torque with a max rpm of about 4500-5000. I'll use an edelbrock manifold, block hugger headers, full MSD ignition and run the thing on propane. I know I need to rebuild the heads regardless. I got the pig for $200 so if it's not worth building up I'll just abuse it in something else. Reliability is the key for my buggy, Keep It Simple Stupid. The rest of the drive train is still being bench raced, a TH-350, chevy 203/ford 205, rockwells seems to be the clear favorite so far.

you can run it as is and have a shit ton of tourqe. there is not a lot of after market but you can quickly get 5-800hp with pistons and cam, very very spendy.


the valve springs are really soft. you can hit them and they dont push bacl, like 60lbs closed. but with a motor that big you dont want to spin much faster than 4500 because you will smoke rod and main bearing swinging that much mass around.

I would look for a TH400

www.500cid.com

they build caddy engines... theres some info there.

you could probably use mostly all of the stock stuff, but the th350 wont live long with that old monster... find some closed chamber heads for the pane... i might have a set sitting here somewhere.
edit: if its a 68, its got closed chamber heads....

it shouldnt need to be bored, the blocks have a really high nickel content, and wear well.

That MTS outfit is on its 3rd set of owners,. I used them many years ago under a previous owner, so I know nothing about the new guy. The previous owner was a businessman who sold parts and paid others to build his engines. Potter Automotive is the place I would recommend as a hard core engine builder who sells parts http://www.cadillacperformanceparts.com/

If nothing else, do the timing chain and gears. The gears have nylon teeth that fall apart and the timing goes all over the place. Plus, the bits of teeth all get sucked up into the oil pickup. Engine runs poorly, really low oil pressure, and you pick them up for cheap.

The nylon teeth all fall apart, it's only a matter of time if yours hasn't. Replace the gears and chain with some proper steel ones.

Check out alaska4x4network.com and do a search for "the freak" it belongs to the board owner he is a very capable fabricator and is running a caddy big block his builup on his buggy includes alot of good info about his engine and tranny picks and sources. I think he may have it somewhere here on pirate as well his name is Brook Greene.

his name here, bgreen.

I just looked up stock specs on a 1968 caddy 472 and it says:

10.5 compression
375 HP at 4400 RPM
525 lbs. at 3000

Sounds like pretty good STOCK specs if you ask me :homer:

hence the snag on my part for $200

Throw an edelbrock intake on it , mild cam , valve springs . You can get header flanges and modify chevy big block headers to fit. dont spin it over 5000 rpm.

the intake is REALLY worth it.

I just looked up stock specs on a 1968 caddy 472 and it says:

10.5 compression
375 HP at 4400 RPM
525 lbs. at 3000

Sounds like pretty good STOCK specs if you ask me :homer:

I believe those specs are gross, not net and certainly not SAE, but they are still impressive and that is with the thing choked down. There is plenty more power to be had with the "easy" stuff like intake, exhaust, etc.

I think it might be worthwhile looking into getting the Ford intake adapters instead of the Edelbrock intake. Using a BBF intake will give you WAY more options including one very important one.

472ci=.273 cubic feet

5000 RPMs*.273=1365 cubic feet per minute

1365/2 (the cylinders only draw air every other revolution)=682.5 cfm

682.5*.75 (volumetric efficiency of 75%)=511.875 cfm

A single Impco 425 is unable to provide enough flow to that engine even with low VE. I really think to get any performance in the neighborhood of what you're looking for you're going to need duals on it. There is a reason these engines had a giant quadrajet on top of them.

Something else that I didn't see mentioned is the factory rocker arm setup. They are adequate for the stock RPM range, but do not like being reved much past 4500 rpm, so you may want to replace them with a shaft rocker setup.

I have a completely original '70 Sedan Deville that is an absolute torque beast. I will roast the tire as long as you want it to and we have used it to tow all of our quads to Little Sahara several times and you can't tell the trailer and 4 quads are back there. We also built a 500 for my dad's '48 Studebaker 1 1/2 ton that will toast mine. I am also going to put a 472 in my '55 F100, so if you can't tell, I'm with you on this one.

Oh, and don't put a TH350 behind that engine.

I believe those specs are gross, not net and certainly not SAE, but they are still impressive and that is with the thing choked down. There is plenty more power to be had with the "easy" stuff like intake, exhaust, etc.

I think it might be worthwhile looking into getting the Ford intake adapters instead of the Edelbrock intake. Using a BBF intake will give you WAY more options including one very important one.

472ci=.273 cubic feet

5000 RPMs*.273=1365 cubic feet per minute

1365/2 (the cylinders only draw air every other revolution)=682.5 cfm

682.5*.75 (volumetric efficiency of 75%)=511.875 cfm

A single Impco 425 is unable to provide enough flow to that engine even with low VE. I really think to get any performance in the neighborhood of what you're looking for you're going to need duals on it. There is a reason these engines had a giant quadrajet on top of them.

That ford adapter shit it is ancient history, went away years ago. Did you click on the link I gave to Potter above, There are more options than just the edlebrock intake avalible. Ive been out of the Caddy loop for 5 years and I can't believe that so many people are giving advice that was obsolete then.

I believe those specs are gross, not net and certainly not SAE, but they are still impressive and that is with the thing choked down. There is plenty more power to be had with the "easy" stuff like intake, exhaust, etc.

This is where I got my info from: http://www.carnut.com/specs/gen/cad60.html

This is where I got my info from: http://www.carnut.com/specs/gen/cad60.html

Too many people pass off stuff at information that they don't really understand. If you don't know the difference between gross hp as was reported in the 60's and net which was used later you might try doing a bit more research.

I have always wanted a 472 or 500 sitting in my garage for later use. Its just one of those things I dont know much about so buying one is always hard to do because I dont want to screw myself. I know certain years and such are different. Good luck with this build though. Keep us posted. Sounds badass!

That ford adapter shit it is ancient history, went away years ago. Did you click on the link I gave to Potter above, There are more options than just the edlebrock intake avalible. Ive been out of the Caddy loop for 5 years and I can't believe that so many people are giving advice that was obsolete then.

It might be ancient, but it works. Our sport is full of "ancient" stuff like old pushrod V8's, 50 year old dump truck transmissions, gear driven cast iron part time t-cases, solid axles, etc. Old doesn't mean obsolete. :D

The point of my post more than anything was to make him realize there is more than just the Edelbrock option out there and that if he is going to run propane and big cubes it might require more than just slapping on old Impco 425 on top of there. In that respect I think we're trying to convey the same point.

don't worry all information is good, I'll just sort out what I find relevant and whats bullshit. I'm shooting for 4500 red line so I hope the stock rocker shafts, connecting rods will be fine for my POS.

It might be ancient, but it works. Our sport is full of "ancient" stuff like old pushrod V8's, 50 year old dump truck transmissions, gear driven cast iron part time t-cases, solid axles, etc. Old doesn't mean obsolete. :D

The point of my post more than anything was to make him realize there is more than just the Edelbrock option out there and that if he is going to run propane and big cubes it might require more than just slapping on old Impco 425 on top of there. In that respect I think we're trying to convey the same point.

Then you might have steered him towards the new manifold from Potter instead of the ford adapters which were out of production 6 years ago.

From everything I read and was advised by Caddy engine builders Ford intakes never really worked very well and 5 or 6 years ago no one was even making the adapters anymore. How well did your engine with the adapters work and how much porting did you have to do to get the runners to kind of line up? How even was the fuel distribution cylinder to cylinder with the ford intake? Im not talking on the dyno, but how was the driveability with the Ford intake adapters? Aside from the ford adapters there was the ill fated Acme, and the Bulldog intakes also long gone. I hope no one recommends that they be used.

I bulit two caddy motors about 6 years ago. A (68) 472 and a 500. when the 472 crapped out i put the heads on the 500. i had it punched .040 over and ran pistons from MTS. I had comp cams custom grind a cam for me, i wish i still had the cam card for the specs. the cam was on a .030 reduced base circle so i nedded .030 longer pushrods. used the edelbrock intake and carb. caddy header flanges welded to chevy big block headers (big pain setting up), Hei ignition and had CMD 32 pound flywheel on it.
Motor ran great and had crazy amounts of torque. I could smoke 40 inch ground hawgs on dry pavement in second gear until i was tired of hearing them.
now the bad news. it was hard to keep cool. i was burning thru starters once a month and i reved it over 5000 rpms (bad chip in MSD) and stretched two rods. when it finally blew. it snapped two rods, broke the cam in three pices, broke the lifter valley and of course the lifters and pushrods fell into the pan.
Caddy websites and forums estimated close to 500 horsepower and 600 toque on premium fuel.

I'm considering rear mounting the rad to keep it safe and so I can mount the biggest aluminum rad I can find. Do you know why you cooked so many starters? Should I upgrade the rods? I was originally going to build a ford 420 stroker, I had a $3k budget for the motor, this caddy was such a stupid smokin deal I couldn't say no.

If your truly keeping it under 4500 rpm the stock rods should be fine. My dad's Studebaker with the built 500 has seen 5500 rpm on the stock rods several times, but we don't push it that hard to often, and it has held together fine.

I was cooking starters due to header heat. I was in the process fo remote mounting the solenoid, but toasted motor before I got around to it. If you keep the RPMS low, I dont think that you will have any problems.

There is a strap that came from the factory to keep the starter from moving around under load that is frequently tossed when people replace starters, but it is very important to keep. You can also get mini starters that will give you a little more clearance from headers

here is one for $400 for the pa folks.....
http://pittsburgh.craigslist.org/pts/977745865.html

I was cooking starters due to header heat. I was in the process fo remote mounting the solenoid, but toasted motor before I got around to it. If you keep the RPMS low, I dont think that you will have any problems.

Were you using any kind of heat shield? Running a Ford style solenoid doesn't keep your starter any cooler. It just helps keep from cooking the little(S and R)wires.

starter issues I'll deal with if I have them.

You going to post pics of your build? I would like to see them.
From everything I've read and heard you dont need to spin these engines any higher than 4000.They make so much torque down low. Also get the biggest radiator that you can fit in your buggy.
I have a 500/TH400 that I want to put in my truck.

I'm still gathering goodies, all I have is a beaten 4 cyl. TJ to start off with, the caddy motor and a pile of steel. I'm not one to waste money, I'm not rich. So far the plans are 47" LTB's, spooled rocks, 4 link front and rear. A member of my Jeep club just dropped an LS1 in his TJ with a 4l60e and a stak case. He's trying to convince me to run a 4spd atlas instead of a 203/205 doubler. I'm wondering if it's worth building a th-350 for the caddy or use a th-400. I'm having doubts a 350 would hold up against that torque monster for long. I'm doing a fair bit of bartering and trading for this project with a friend who owns a tranny shop and another friend who owns a small 4x4 fabrication shop. I'll post pics when I actually have real progress instead of fishing for knowledge.

Do it once and right get the turbo 400.

anybody run this kind of power through those atlas' or stak cases? how well do they survive on the rocks and in the mud in a moderately sized(about 6k) juggy?

i just came up on a new truck and am wondering if a 435/465 can be used behind ethier the 472/500?

fly wheel, balance?

searched and found, there are tons of flywheels available, aslo oattern adapters. the tricky part is the end of the crank needs to be bored out for the pilot.

I use a double pattern t350 behind my 500 with a reverse manual valve and super aggressive shift kit. I don't have the breakage issue people talk about. I would not use the t400 just because it's harder to find if you broke it . I spin welded 60's and 40" boggers in a 5300lb jeep and my tranny stays together fine and has not been rebuilt in 9.5 years Most 350 tranny breakage I see is because people don't fab up or use a proper t-case torque mount and they break the 4 bolts outta the rear of the tranny or bust the whole back off completely. Atlas' and 205's are still heavy and only held on with those 4 bolts so proper mounting would be key to a long service life in my opinion. The impco 425 richened up seems to feed this engine just fine. I know of the 460cfm limit but that limit seems to work well with vapour systems such as propane . Higher cfm gasoline carbs deliver more air for sure but through rich liquid mixtures. Just my 2 cents

I have 2 th400's on my back porch right now. want em? both are Buick/Olds/Pontiac/Cadillac patterns, and I run a bbc. all they are good for to me is a couple of spare internal parts.

I would go with a th400. Sure, it uses the most power of any automatic, but its undoubtedly stronger than a th350, cheaper and stronger than any 700r4, has the most options available for transfer cases, and its a simple unit to use. Electronic kick down, only needs one power wire.

they were used behind 472 and 500 inch caddy motors from the factory, will hold up to 30k lbs.

the th350 isnt a bad trans, certainly better than any 700r4, but it has a limit between a heavy foot, huge torque and big tires.

thats my .02

Even though this is a mud truck it a 500 caddy and a very mild one at that.

stock pistons, stock rods with arp bolts, early heads only gasket matched, comp high energy 268 cam, performer intake with 850 holley, bbc 1 3/4 headers.

Has msd ignition with a 4300 chip.

Rest of truck is 400 turbo with stock convertor, np205, rockwells, 15.5x20 michelins on double beadlocks

Truck weighs 7.5k and runs very well for a being that weight. It does not seem to build lots of Hp but has tons of torque everywhere.

YouTube - Richard GREEN - MudStock Sept 07 Mud Bog, Sparks Oklahoma (http://www.youtube.com/watch?v=dhKpXoOdfzk)

Do the caddy engines have 5 headbolts like a sbc? I wonder if they would hold boost from a turbo? Could be the ultimate low buck high horse motor with a big turbo off a semi.

they have 10 head bolts like a ford 460. they are big. you dont hear a lot about them blowing head gaskets either.

I think i have a pair of early high compression heads around here somewhere, ill have to find the casting number...

I thought about the turbo idea, just didnt have room to package it. The nodular iron crank would hold up well, i think, but the stock rods would not like it as they are cast, not forged.

We have been tempted to try the 4340 I beam rods that are on ebay for like $240. Figure even being cheap rods they are probably better than the factory cast peices.

they will probably hold up fine if its not going past 6000 rpm. Sure the pistons are heavy, but you can find lightweight ones out there.

Don't pay extra for a repackaged aftermarket starter. Chevy and Buick starters fit right on. I run a Shmucks chevy geardrive starter on my 509 Cad.
The Edelbrock intake is the cheapest and bestest for the street.
Use a Buick or Pontiac stick bellhousing and slap a 435 or 465 behind it. I don't recall if a centering ring or turning down the tranny front bearing retainer is necessary. Olds bells don't have the starter clearance 'cause the starter is on the driver's side. Drilling out the Cad crank for a stick is easy, it is just for clearance for the input shaft and a handheld drillmotor is accurate enough.
I HATE the factory valvetrain. The minimum rocker setup is the stupid shaft upgrade, but it uses Ford or Buick rockers and the cam needs upgrading to compensate for the lower ratio rockers. If your machine shop doesn't know Cadillac heads (none of them do), then you will need to get custom pushrods for each and every cylinder. Aftermarket heads ($2500+) have individually adjustable rockers.
If you just pull an engine to slap it in your truck, change out the old nylon covered timing gears, the original springs are amazingly weak, and headgaskets have been known to rot out.