500 Swap

[61caddillac]

Hi everyone any info will be very helpful to me.

I got a 1961 cadillac 4 door with OEM 390 so I am planning to do the 500 swap with Turbo 400 long tail. I just got the engine and trans has anyone done the swap? Will headers fit?    I guess I should have asked this before i got everything.

My email is tgr12344@aol.com

[Otto Skorzeny]

You will get a lot of answers here:

http://www.modifiedcadillac.org/forum/index.php

And here:

http://forums.500cid.com/

And buy products, adapters, etc. here:

http://www.500cid.com/Home.htm

[Walter Youshock]

Why swap it?  The 390 was one of the the BEST engines ever made EXCLUSIVELY by Cadillac and the one that belongs in the car.  It was so good that it was in production for four years.  It powered some of the most admired Cadillacs from 1959-1963.

At least save the original engine so, if you sell the car, the matching engine goes with it.

[Dave Shepherd]

In reality the 500 after the 70 Eldo version was really a detuned engine that performed at a minimum, the 390 except for displacement is a better engine power to displacement.

[TJ Hopland]

At least he is wanting to stay with caddy power, and he likes the look of big Cadillacs.   Those things should be worth a few points.  Lots of guys would want to shove a chebby in there with a blower sticking out the hood. 

 
If its a museum piece or an occasional sunday fair weather driver keep it original but for a regularly driven or daily driven car I almost always go with whatever is going to be easier to find parts for especially if it does not require non reversible mods to the rest of the car.  The 500 was a solid motor.  Its fairly easy and cheap to get the power out of it if you dont need to meet the original emissions standards.  Most common parts are still available in stock at typical auto parts stores or worst case the local distribution center so you have them next day with no additional cost.  Thats an important factor for a car you plan to drive a lot. There are even quite a few options for 'hot rod' parts if thats what you are into. The basic design of the 500 was from 68-81, thats a pretty long run.  They listed the 368 8-6-4 as an option for the CC 82-85 but I have never seen one.   Lots of those cars sitting around rusted out that can be had cheap. 

The modified site guys will tell you what you need to know. 

If he does not keep the 390 I bet he will post it for sale here so someone else can keep their car original.   

[Dave Shepherd]

Cyl head ports and the intake were the big performance restrictions on those 500 engines, yes you can get AM heads and intake and gain a lot of power, not cheap.  The connecting rods were done a 5k, so this engine has some real limitations, but hell this is a Caddy, like you say.

[Chris Conklin]

I got a 1961 cadillac 4 door with OEM 390 so I am planning to do the 500 swap with Turbo 400 long tail.

Any problems with the 390 that make you want to do this? Or you just want to do it to do it? Size really isn't everything ya know. My daughter's four cylinder Accord Coupe will put out as many horses as the 500.

[Sweede64]

Any problems with the 390 that make you want to do this? Or you just want to do it to do it? Size really isn't everything ya know. My daughter's four cylinder Accord Coupe will put out as many horses as the 500.

The accord doesn't put uot 500lb/ft of torq.....  hovewer, the -69 -70 472 is a better choice, but nothing will fit. If you go thru whit this why not put a 200r4 tranny behind it?