500 ci engine

[BigJohn]

Hey Guys,

I just joined and I am interested in the possibility of building a 1970 500 ci engine. I have some questions that I hope you guys can help me with. After reading some of the other posts about engines I think I can also help some of the other guys with their engine questions.

1. Can you build a caddy engine with 1hp per cubic inch like you can a chevy? How difficult is it?
2. Budget? Can you do this with about $3000.00?
3. The book "How to build Vintage Hot Rod V8 engines" has a section on building a caddy. Have any of you guys read this book and is it worth purchasing?
4. How hard is it to port a set of caddy heads? Does the shop that does it need to have experience with a caddy.

Thanks for the help,
Big John

[Montiac]

Don't see a problem,especially if you spray it.You would just have to shy away from cast pistons if you did. Contact AL,the owner of MTS he has alot of knowledge for making Cads go fast! BTW get the "Big Inch" book from Al it tells you what you need to know.
Hope that helps........

[BigJohn]

Thanks for the re. I will get that book before I start on the engine so that I can have a game plan.

Thanks
Big John

[Vern]

My two cents. No pro hear just a somewhat experienced Cad hot rodder.
1 Yes On pump gas at that and without spray.
2 Hmnn I spent $3,512 on mine but it depends on how cheap and lucky you are with regards to your core/parts what machining needs done and how much you pay for it. I was cheap but tried not to be stupid cheap.
3 I am not familiar with this book.
4 Well I am not a head porter but had a set ported by Donovan. If you are buying pistons anyway then get a set of early heads (76cc) and screw the late 120cc heads. You are safer with an experienced Cad head porter. My understanding is that an experienced head porter should be able to get about 280 cfm at like 5.50 lift with a 2.19 intake valve at 28 water on any early heads with a moderate amount of port and flow time. ie a street strip port job.

Mine used 40 over cast pistons, reconditioned stock 500 rods, quality rod bolts and the assembly was balanced. For 500HP you don't need more. Al says new cast pistons are safe to a 200HP shot with a reasonable rpm. It is hard to learn that spinning these much past 5000 does not benefit you or make you go faster unless you have race ported heads and a cam etc to match. That being said if I were building it today I would spring for Als new rods and a custom piston. Think big on the piston. It helps the heads flow in part by unshrouding bigger like 2.19 valves improves bore to stroke ratio for more rpm & horsepower. (we already have all the low end torque we need) I like the idea of a 4.381 bore for a 519 with a Cometic head gasket. :)

PS Any year block later ones came with HEI and electric choke carbs if that is important to you. Early heads 68 thru 73 I think and any year 500 crank. Naturally a 472 crank works fine also and may have some advantages for certain build ups. For power spend your dough on heads and headers for longevity you would want to spend it on the bottom end first.

[BigJohn]

Thanks for all the info. That helps a lot.

Big John