Big inch Cadillac

[78 Chevyrado]

I got another "good" idea.  I'm off tomorrow to look in a couple of places for my next engine.  Hopefully I'll end up with a Cadillac 500ci.  I got a couple of leads on some 70's eldorados.  Roadtrip!  Let yall know what I find out.

[TexasRed]

Have you read the article about Dick Miller's 541 Cadillac Stroker Engine?

[78 Chevyrado]

Yep, I read that one.  basically why I havent been around the forums much is I'm reading all the cadillac 500 stuff I can find.  I'm about to order the big inch cadillac book to find out more, and I like having more car books. 

None of my hunts materialized, one of them was gone and one was a 472.  Hey if I'm gonna go for it I want a 500, if nothing else than to say I have one   At least the search for one of them ended in having dinner and some beers while shooting the S&*$.

I'm not super serious on finding one immediately, but I'll buy one up if i find one for a good deal.  Perfect scenario would be buying a whole 70-76 eldorado for less than $800.

All the info I can find on 472's and 500's tell me it's the engine for me.  They were the cream of the crop for gm and the info tells.

[Blazin]

I have a 30 over 403 olds I am going to put in a C10 one of these days. Can you say tire fryer!

[zieg85]

A great friend of mine, know him since kindergarden, has a 69 C20 Longhorn with the 501 Eldorado front drive train, FWD.  It really turned the heads when he lit the front tire up.  The story about that truck is his dad and grandfather put a car a week together, go to the auction, sell it and haul another one home to fix.  This truck was totalled with next to no miles on the odometer.  The thought out of the box on this one.  He still has the truck today.

[werewolfx13]

A great friend of mine, know him since kindergarden, has a 69 C20 Longhorn with the 501 Eldorado front drive train, FWD.  It really turned the heads when he lit the front tire up.  The story about that truck is his dad and grandfather put a car a week together, go to the auction, sell it and haul another one home to fix.  This truck was totalled with next to no miles on the odometer.  The thought out of the box on this one.  He still has the truck today.

Can you get some pics of that? That sounds like an interesting swap. Not something I'd do, but interesting to see nonetheless.

A 472 is a dang good engine, much more mod friendly than a 425, not quite as big or commonly used in swaps as a 500, but its still a really nice engine..

[SUX2BU99]

Nothing wrong with a 472. Just a little smaller bore and stroke from the 500. Otherwise they are the same pretty much. Make sure to get one with the 76cc heads and not the 120cc smogger heads.

When I was looking for a truck to buy before I bought mine, a local guy had a 77 2wd stepside that he put a 500 Eldo FWD drivetrain in. I think he wanted 5k for it. The only question about that is the quality of work that was put in to swap an entire front suspension, steering and drivetrain from another vehicle. I imagine it would require chopping the front frame off and welding the subframe in from the Eldo. That could be scary with substandard welding. I would be curious though how these swaps are done.

[HAULIN IT]

Sux, Actually the bore is the same...The stroke was just increased from 4.06 to 4.30 to make a 500, the pistons are different to make up for the increased stroke. LOOK at the numbers on that 500! 550 lbs, That would be killer. I bought a nice running 77,000 mile one from a rusty Eldo a few years back, complete with a HEI, RWD motor mounts & exhaust manifolds (from a 425) for $200 or $250. I built a little cart & rolled it under the workbench for a rainy day    Lorne
 

1970    None    None    472    375 hp @ 4400 rpm    525 lb·ft @ 3000 rpm    4.300 X 4.060    10.0:1    35-40
1970    None    None    500    400 hp @ 4400 rpm    550 lb·ft @ 3000 rpm    4.300 X 4.304    10.0:1

[78 Chevyrado]

I like that they wear so well from a high nickel content block and they are light to be so big, with an aluminum intake they weigh only 30-40 lbs more than an iron head chevy small block.  The main thing I like is I don't have to hot-rod it to get the power I want, which makes it even more reliable and long lasting.  All i want is 500ft-lbs that will last a good long time and this would fill that bill nicely.  One of my uncles used to have a machine shop and said when those caddy blocks came through, at 100k+ miles all they needed was bearings and a re-ring job and they were good to go for another 100k.  He also said he hated when they came to be bored because they would eat up the cutters a lot faster because they were so hard, the only block he said was harder on the tools were the old hudson blocks.  Another thing I've seen in service manuals is that the heads have a high enough nickel content that they don't even have hardened valve seats.  From what I've heard it'll go in pretty easy.  I'll just use a tranny adapter plate and swap the frame mounts left to right and redrill the holes and buy some header flanges for the caddy to put on a set of BBC headers.  << Nothing goes that easy, but you know what i mean

[chirim2003]

i have an 83 gmc and am interested in it also.  i have been hitting the caddy forums and the online caddy parts places to scope it out.  i am thinkin mild rebuild on a 500 with a 4l80e and np205.  i have gotten conflicting info on mounting the engine in.  some say stock mounts flipped around and redrilled and others say custom mounts and alot of fab and welding.  does anyone know for sure?  i havent found a specific engine mount for the swap for sale only universal kits that have mounts and new frame mounts to be welded in.  but it sounds like a good way to get the torque i want.  i also will be puttin a holley fuel injection on it if i do it.  will be interesting.

[Chevalade]

Well for starters, the swap has been done many, many times. There are a few really good caddy sites with tons of info on the 472 and the 500.

I am also doing this swap, but am aiming a lil higher than just 500ft/lb.

Stock mounts flipped and moved forward about an inch and a half should do it. Make sure you use the caddy mounts. Or you could get ahold of Marty at MTS Specialties. They have universal mount kit.

Intake, heads, cam, rockers are the biggest holdback. Mts has a new FR aluminum head that flows around 330 out of the box, and they have a nice shaft rocker setup. They have a few grinds for cams as well, for most of you the MTS-10 or MTS-15 cam will be more than you will ever want. As far as intakes go, right now the MTS SP (single plane) is the best out there. The edelbrock is good if you don't plan on turning over 4500 rpm. Stock valves will float around 5k. They also have better rod/piston combo for cheap.

Depending what year your motor is, you will either have the 76cc or the 120cc chambers. Flat top pistons and the 120's will give you a 10-1 cr. Or  you can get the 28cc dished pistons for a 10-1 on the 76cc heads. There are a lot of variations between the years of production. A lot of people don't know the difference between the 472 and the 500. To tell, take out a sparkplug, stick a wire down and measure the stroke. From the outside they are virtually identical.

If you really want to go crazy, google Potters Automotive. They are always trying to push the envelope with power on these motors.


My plan is to build a twincharged 523, with 2 s475 turbos feeding a 6-71 blower, with fuel injection. Costly, but different on so many levels.

If you need more places to look or ask for info, let me know and I can get ya dedicated cad sites.


Ryan

[Chevalade]

One last note.....

They are BOP style bellhousings, and you can get lots of TH-400's in that style. So no need to modify rear driveshaft lengths.



Ryan