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Cadi Vs. BBC

R

Rossc

Member
I was thinking of using a SB or BB Chevy with a 2.68:1 gearbox. I see a lot of people using the Cadillac 500. Why the Cadi 500 over a BBC? Are the Cadi motors more plentiful? What year models would I look for to find the 500CID engine? I'm a Chevy man, so my first instict was to use a Chevy motor, but if the Cadillac can be done cheaper.... I assume the popular gearboxes are available for the Cadillac motor. I know they are available for the Chevy motors.

Thanks....Ross
 
caddy aint cheaper if there done right main advantage cad torqe monster wieghs less airboat are like airplanes need torqe and need to be light, check water thunders site ls 1 450hp with 268 box every thing ya need complete deal ive done the math you cant put a pakage togeather your self for less an hell back it tune it and tell ya what it will do before it hits the water, believe me youll be way ahead of the curve
 
plumcrazy":31wg5vmg said:
caddy aint cheaper if there done right main advantage cad torqe monster wieghs less airboat are like airplanes need torqe and need to be light, check water thunders site ls 1 450hp with 268 box every thing ya need complete deal ive done the math you cant put a pakage togeather your self for less an hell back it tune it and tell ya what it will do before it hits the water, believe me youll be way ahead of the curve
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What is waterthunders web site? It's not listed under his profile. Thanks
 
First off a Caddy is a GM motor. It is lighter then a BBC and with an aluninum intake it weighs about 60lbs more then a cast small block. Caddy motors cost next to nothing to pick up a good block at a salvage yard or ebay. Most people have no clue to what they are and they look for a BBC. Waterthunder makes the only small block that I would buy for an airboat period because he builds an aluninum motor that will give you a crazy power to weight ratio. Dollar for dollar I feel you get more for your money out of a Cadilac motor if you are going for big cubes.


These are my own opions and I hope I did not ruffel any feathers.
 
A 472 or 500CID Caddy motor is proving hard to come by. Every salvage yard I've talked to says that anything that old would have been crushed. I'm now on the lookout for a complete car....cheap.

Might just go SBC. They are cheap, easy to come by and cheap to build up.

Ross
 
Where do you live, the cowboyseven.us site has members all over the us and world .(it's a 500 Cadillac forum) and surely someone can get you a core there. For a boat, you'll want a 500 as it has a .250" longer stroke and more grunt down low, otherwise ,they're identical. If you get a complete car from a bone yard, you can scrap the carcass for $250 or better. Labor intensive, but cheap! It'll help you get to know your engine better though, especially if you wish to build your own. Otherwise, have a dyno proven crate engine built with no core charge.
 
If you did not live so far I would tell you to come by my house. I have one complete core and extra crank. Richard had the correct idea, buy an old Caddy and remove the motor with a torch, then scrap the car to recover the cost of the motor.
 
you have to be carefull with ebay cause every single caddy seems to be a 1970 model or 500hp.unless they know for absolute sure it is a 500 it could be a 472.
 
Also keep in mind that only 75 and 76s are for sure 500s. They also have "less desireable " 120cc heads. All earlier rear wheel drives with mid sump oil pans were 472s. Only eldorados prior to 75 and 76 with rear sump pans were 500s and they started the first one in 70. All the blocks after 70 are the same til 76. Last 4 digits on casting are 5200. 472s and 500s use same block on 70 & up. 4 out of 5 cores I end up with are 472s now, unless they have the 120cc heads. That's OK since I know they at least have a 500 crank and I'll build them and add the 76cc heads from another earlier engine. Last 3 digits of 76cc heads are 902, 950 and 250. Under the v/c. 120cc heads are last 3 552 and 493 IIRC (correct me if I'm wrong guys) . Stay away from 425s for the boats especially. 77-79.
 
Cadillac Performance Pts.":2mgq4mrb said:
Also keep in mind that only 75 and 76s are for sure 500s. They also have "less desireable " 120cc heads. All earlier rear wheel drives with mid sump oil pans were 472s. Only eldorados prior to 75 and 76 with rear sump pans were 500s and they started the first one in 70. All the blocks after 70 are the same til 76. Last 4 digits on casting are 5200. 472s and 500s use same block on 70 & up. 4 out of 5 cores I end up with are 472s now, unless they have the 120cc heads. That's OK since I know they at least have a 500 crank and I'll build them and add the 76cc heads from another earlier engine. Last 3 digits of 76cc heads are 902, 950 and 250. Under the v/c. 120cc heads are last 3 552 and 493 IIRC (correct me if I'm wrong guys) . Stay away from 425s for the boats especially. 77-79.
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Richard,
another quick way to ID a 500 is by looking at the tail end of the crank I think. I attached a link that has many helpful tips in how to ID an elephant.

http://www.geocities.com/MotorCity/Pit/9364/guide/Engineid.html
 
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