Unique 500+ Cubic Inch Engine Swap

[Jrainman]

[QUOTE=kwmech;8627468]From about 1973 and newer all the big cube engines were facing lower compression and retarded cams to meet emission requirements. I think the 454 got down to about 7.5 to 1 compression. Doesn't take much to wake them up. Jump them up to about 9-1 and add a mild cam and make those cubic inches come alive. Night and day difference[/QUOTE

EXCACTY Sleeping giants just waiting to be woken up , with little effort. and a great $ to HP gain value.

[toolboxchev]

The pre DEQ, EPA Cad, Buick, and Pontiac Big Blocks were flat out ground pounding torque monsters stock, your looking at Pre 72.

Anything after that is junk, low compression, weak cams and low numbers.

I can recall a drag race in a downtown area 18 years ago. My buddy picked up a low mile 4 door Delta 88 in mint metallic green with a big block and posi. 69 or 70 I believe. Fricken bench seat in it was larger than my trucks.

Raced a couple of dark haired swave guys in a 77 vette, stoplight to stoplight.

Flat out, smoked both of the rears, marked the pavement, and clouded the entire block going by those two swave gents.

When we got to the stoplight, a bystander commented: That was "THE" ugliest drag race he had every seen!

Find the right Caddy block and Heads. Add a Turbo later. I know I would be happy!

[Steeveedee]

I have a stock 400/400 with a 3.54 axle, and I'm happy with it. I got a hole shot on some dork in an Infinity with fauncy wheels and a 4 inch fart can on it. Or maybe two fart cans. He was winding it up at the light, so I couldn't resist. OK, I only beat him across the intersection, because I was doing 40 MPH by then, and I'm no longer the rebellious law breaker that I used to be.

[fourspeedwagon]

The 500 Cad would get the vote a hundred times over from me. I love oddball as much (probably more than) the next guy but that v6 was an odd duck that was put down for a reason.
Caddy bb is a marvel. Huge power/torque, moderately light (lighter than bbc) and as mentioned efficient enough to give decent mileage. 3 to 4 times what the v6 will give. The v6s I was around averaged 4 mpg. Very discouraging and it won't turn the rpm the 500 will.

[1972RedNeck]

Interesting thoughts from everyone. For sure, the Caddy has the low weight going for it.

On a completely objective note, does a V6 actually get that bad of fuel mileage? I have a '65 GMC 5000 6X6 with a 351c V6 in it. It has a direct drive 5 speed and 7.17 gears and weighs 16,000 lbs empty. Running wide open, flat out (45 MPH) hauling an additional 12,000 pounds for a total of 50 miles I got about 4.5 MPG.

If I remove 22,000 lbs, cut the gear ratio in half, and add overdrive, I highly doubt that the fuel mileage wouldn't drastically improve.

Stock they are 7.5:1 compression and the vast majority of them wound up in large trucks that were loaded to the hilt. If you bump the compression up to 9:1 and put it in a light pickup with tall gearing, why would it get any worse fuel mileage than a similarly built Caddy?

As for the RPM, I want a low end grunt engine, and by the time I have the crank ground and balanced, 5K will be no sweat - heck, the 500 Caddy will still have a longer stroke.

[1972RedNeck]

Originally Posted by LockDoc

As long as you are looking for something unique with lots of torque why not use a GMC 702 V12....

I actually had a line on a pair of 702's close by a couple years ago for $2500 a piece. If I was a better bodyman, it would be a fun project for sure.

Originally Posted by Steeveedee

I have a stock 400/400 with a 3.54 axle, and I'm happy with it.

I would be satisfied with that as well. My '66 Ford is built similar with a stout 410 (390 with 428 crank) mated to a 5 speed with 3.54 gears. Runs great, gets decent mileage, pulls well, etc. I am just looking for a little (well, maybe a lot) more...