500, 472, 425, 368 Discussion, Rebuilding a 1971 500 in Cadillac Engine Technical Discussion; Hi, my name is Rob, and I've been hanging around this forum for awhile soaking up the information. I'm currently ...
Hi, my name is Rob, and I've been hanging around this forum for awhile soaking up the information. I'm currently restoring a 1971 Eldorado Convertible. So far I have a new top, it's getting painted in a few weeks, custom dual exhaust with cutouts, and an edelbrock 750 cfm carb. The car sat for 7 years before I bought it so I've decided to rebuild the engine before I go any further. After the engine is rebuilt it's going in for custom headers to finish off the exhaust. I'm looking for advicde on what to do with the rebuild. I've been looking at a lot of aftermarket parts including camshafts, cylinder heads, pistons, etc. As you can probably tell from the dual exhaust and cut outs I'm going for more of a hot rod type of ride, but I still want to be able to drive around with family/friends comfortably without the car killing us (i've come to call it my luxury race car project). I want to do some basic power additions and am wondering what the best way to go would be. I've heard that changing the cylinder heads is often a bad idea...any advice you guys have would be appreciated. Thanks in advance for any opinions.
I'm working on a '76 Eldorado "sleeper" project myself.
Go to www.cadillacowners.com and click on "Vendors" on the left side. This will show a list of companies that make aftermarket parts for this engine. You should e-mail Al at Maximum Torque Specialties and tell him about what you are trying to do. He'll be able to suggest a cam, etc that would be ideal for your application.
What kind of power are you looking for?
I don't know how much we relate, as I'm going for upwards of 500 horses and 500 ft. lbs of torque.
I'm looking for more around 550 hp and upwards of 600 tq...I'm not sure if this is possible while still maintaining a nice comfortable ride and an easy to drive car...but thats what my goal has been. Any ideas on what I should do? And thanks for the idea to email Al.
Alright, sounds like we are doing about the same thing.
Like myself, you will want to go with new pistons and rods. How do the cylinder walls look? You may, but probably don't need to bore it. If you want to for the hell of it, then you could go .030, .040, .060, etc. over.
Al will be able to tell you what cam you will want to use, etc.
I am going to be running a custom EFI setup using the Megasquirt controller. Have you heard of it? You may want to look into fuel injection.
If not, Potter Automotive makes some really sick intake manifolds.(among tons of otehr great products for the 500. Make sure you give them and MTS a good looking over. You'll see many things that interest you I'm sure.)
There is also the option of going with the Edelbrock, or modifying your stock one as shown on cadillacowners.com.
I'm glad to know that I'm not the only one that wants a hot rodded Cad 500 in the body it originally came in. (Although I sure would love to throw one in a '72 Nova
Also on the Vendors page, check out Flashcraft's site. Havn't heard much about them, but they make a set of headers for the 500 that will fit in your '71 Eldo. MTS makes header flanges if you want to make your own or have a local maching shop do it for you.
Anything else, just ask. As said before it's cool to have someone doing the same thing to almost the same car
It is good to hear that I'm not the only one that wants to hot rod it in it's origional body. The local cadillac club thinks I'm crazy not keeping it stock. I was looking into EFI but I like the feeling that the engine gives when the secondaries open wide at higher RPM's, and with the cutouts I'm running it gives an awesome aggressive sound that I don't want to ruin. Do you know if the Potter intakes allow you to keep the AC compressor, because I know the Edelbrock ones don't. The cylinder walls are in really good shape, the and the cylinder heads have a little rust on them but nothing that isn't manageable, so I'll probably be keeping those stock. Thanks for all your advice, and please keep me posted on your project.
Yeah, The hardcore Cadillac fans think you are crazy/stupid/whatever for not keeping her stock, and the hardcore hotrodders think it's a waste. My project sprung from fixing an exhaust leak, seriously!
I'm not aware of any intakes that allow you to keep the original A/C compressor, but I have seen it mentioned somewhere either on here or on the MTS forums that there is a compressor that will fit on the Edelbrock. I'll try to find the post or the compressor.
I know what you are saying about the secondaries. I love that too. I went with the fuel injection because I was sick of fooling with the Quadrajet, and thought it would just be really cool. Also I like the idea of having no flat spots, etc. that you find with carburation. One thing about the MEgasquirt thing that really got my attention, however, was the fact that I can tune the engine with the laptop. Me, loving computers and cars, think this is just one of the coolest concepts ever.
Glad to hear about your cylinders. Mine had just a tad bit of scratching, so we decided to just go ahead and bore it .030 over, making it roughly 507 cubes.
I am currently working on a "log" of the project so far on picturetrail. I created the account, just need to upload all the pictures.
I'll keep you posted. Once again, it's cool to have someone doing the same thing to help me and to share facts with, etc. Do you have AIM?
If you are looking into the Edelbrock intake, I would go ahead and modify the stocker. It is way cheaper, and can fit the compressor. Go to www.cadillacowners.com (AGAIN! lol) and on the left click on "Manifold". It shows how they machined the center out, and the flow figures compared to the Edelbrock. The modified stock intake flows at 94.5% of the Edlbrock AT WORST.
If you find that compressor that will work let me know. I got rid of the quadrajet because no matter how many times I tuned it, it still ran rough. I put on an edelbrock 750 cfm replacement that bolts right on to the stock manifold and it was like night and day. The car had an instant boost in hp and tq. I have no complaints with it, as it's run smooth ever since. I like the idea of modifying the stocker, and it doesn't look that hard to do. If it runs at 95% most of the time whats the point in spending an unnecessary 400 dollars. The idea of tuning it with a laptop is extremely enticing, but I'm not sure it's the way I want to go...I will definitely have to look into that more. I do have AIM...talk to me any time...it's cadman71eldo. I can't wait to start buying parts...and get this project off the ground...