'87 Chevy daily driver weekend warrior + 500ci

[ChevyTurk]

Hello,

     I have an '87 Chevy 4x4 Pickup (shortbed) on 4inch leaf springs, holding a D60 upfront, 14bolt(detroit locker) in the rear with 4.56 gears turning 36" Swampers. I have a what I believe is a '75 500ci caddy in my shed with low compression heads. I have a vendor in mind to get all my parts and do my heads. I can turn wrenches but I'm lost when it comes to the lingo about the internals of an engine. I know the parts, but trying to decipher cam numbers is alien to me.

My truck will be a daily driver for probably two years before I can retire it to weekend use only. On the weekends it will mostly see trail riding in North Florida terrain (sand and mud). I am not a hardcore mudder and never plan to tach out my engine when in the mud. What kind of cam am I looking at? and what is that neat equation to figure out RPM at speed? I'm looking at your typical TH400 tranny to make it all work. If my tire/gear setup is too steep for extended highway use, I am considering a over/under drive unit, I think Gear Vendors sells one.

Thanks for your time and putting up with yet another newbie

[~JM~]

Greetings ChevyTurk,

Welcome to the board. Sounds like you have a great truck & an excellent foundation for a Cadillac swap. Please post up some pics if you get a chance.

Have a look at the first 3 posts at the top of the "Basic Big Block Cadillac" section. http://caddy500.com/index.php?board=2.0

That should provide you with an exploded parts diagram with much of the correct nomenclature. As far as understanding camshaft specs...  Good luck.        The study of camshafts, cam specs & the corresponding effects upon your engine, could easily become a life long obsession. The camshaft could be considered the "Brain" of your engine. The shape & placement of those egg shaped lobes are what defines the performance characteristics of your engine. Unfortunately I cannot help you in selecting the correct camshaft for your rig. I have read & studied enough on the subject to just begin to barely understand how in depth the subject can become.

I see that you mention that you have been in contact with one of the aftermarket Cadillac parts vendors. That is excellent. I always recommend to anyone new, to contact all of the vendors & talk to them. Ask intelligent & specific questions to learn as much as you are able & to determine which vendor you feel most comfortable with. If you're real lucky, the vendor of your choice won't be too far away. Once you have that settled, ask the vendor to guide you in selecting the correct cam for your application. Seems like most failed or fouled attempts at building a Cadillac engine are usually due to sloppy machine work (especially in the heads), poor attention to detail /sloppy assembly work and incorrect camshaft & valve-train selection. I'll stop here for now & let some of the other, sharper guy's jump in. There are several camshaft posts on this board for the searching. When you have a few moments, see what you can dig up. One of the common problems that other engine builders have, is usually not a problem for us. That is selecting a cam that is too large. Generally we end up with one that is too small.  

[dave brode]

welcome.

Post with head casting #s [under valve cover in center]

Measure stroke with wire through plug hole. 500 = apx 5 & 5/16, 472/425 = apx 4 & 1/16"

 If you can't feed the engine at high rpm, it is not going to rev anyway. You do NOT need to rev these engines like a sb chev. Imo, the best thing you can buy is a rev limiter. The internal parts are heavy. No sense revving it, it's unkind. Torque will pull you though the mud. Unless you buy well ported heads with big valves, cam and rockers to suit, you will not make any power above apx 4600.

Example = two year ago, I ran a re-ringed '75 500 with stock valves, porting, edel intake and a 232/240 at 50 cam with .536" lift. It ran best shifting at apx 4700. It would go higher, but would slow down. Truck went 19.97 on 87 octane, btw. The engine in my truck now is a high compression 514", with ported early heads, 2.18/1.84 valves, but I'm still running an #2115 edel [limiting rpm]. It runs best shifting around 5700 [11.66 at 114]

Dave

[ChevyTurk]

I have 120cc heads. I'm currently in Iraq so I cant go look at the casting numbers, but I know I checked them before and they are the 120cc variety. The only thing I didn't do is measure stroke or get the # off of the crank because I couldn't spin the crank. The engine is fairly ruff. wasn't sealed well when stored. the old man I bought it from assured me it was a 500 though. But I still have to check the crank when I get back to make sure.

I'm just trying to get ahead of the game as far as what I want to do with it when I get home. I know I need new push rods for sure, because they are some adjustable kind, doesn't seem very sturdy. And I think a 4500ish rpm redline is just fine. I definitely do not need more than that with this motor.

[dave brode]

It probably is a 500, as the only 472 that had 120s was the '74.

Be careful over there.

Dave

[ChevyTurk]

Well, I eventually got a reply from the vendor via email and the cost to build the motor I 'wanted' is a bit high. I'm assuming the quote he gave me was for his shop to do everything though. I really wasn't planning on putting 7 grand into just the motor. I was hoping to do the entire job for less than that.

I have one vehicle I need to sell before I commit any funds to the Caddy, so that is an unknown right now. However, What exactly can I do to my motor to refresh it and get a little more juice out of it without spending a down payment on a house?

[OldSub]

Can you post what he was going to do for $7,000?  My first reaction is that's too much to simply freshen and mildly modify one of these motors.  Maybe dial back the performance mods a little and do more of the work yourself?

[ratnasty]

i'll sell ya my hole truck with a 472 with alot of goodies for $7K its a beast just check out my info! or call 502-690-0877!yes it is drivable!