Cadillac 500 Build for my 1984 Regal (LOTS OF PIX)

Here's a story about my car and engine.

I bought this 1984 Buick Regal in fall of 2011. Picked it up 9 hours away from my house, and raced it the same day where I picked it up. Laid down a 13.6 @ 102 off the trailer which was the best of 3 runs. Figured I could get that down to basement 12's with a bit of tweaking. Drove it another 3-4 times to a new race track near home, and it blew a headgasket and chewed up all the bearings on the first pass. Since fall of 2011 I have since been trying to "fix" the issue, which has gotten seriously carried away into an all out engine build.

This is the story of said engine build.

The car as I bought it;
1984 Buick Regal with Cadillac 472 engine that experienced a head gasket failure. It was a 1968 472, with 10ish:1 compression, crushed peanut pistons, 76cc stock heads, MTS#15 cam, cloyes roller timing set, ARP rod bolts, and ARP head studs. Adapted Buick rockers, and beefier valve springs. Custom oil pan, 1 header, and a custom main cap "slip on" girdle. Edelbrock 2115 intake, and an Edelbrock 750cfm carb.








Luckily I had also been given a spare Cadillac 500 with the car (core) but it was a low miles untouched engine. This 500 is what is destined to take the 472's place.


Carnage pictures of the 472;

Re: Cadillac 500 Build for my 1984 Regal

Then it was a long journey of learning many lessons about machining a Caddy, and dealing with deadbeat machinists. As well as trying to select all the right parts and changing my mind many times over. The engine was assembled and very close to running in August of 2012, but had to redo it again, because the clearances I spec'd didnt check out, and we basically had to redo it all. Skipping all the boring stuff, here's a pictorial history.

Started by disassembling the bone stock low mileage 500 to ensure it was a good core. The bearings were so good, it could almost have been cleaned and reassembled as is. Not bad for sitting around for 30 years.

Bought some new goodies;
Probe Forged pistons +.050 10:1. Forged Hbeam Rods. Beefy valve springs. MTS#15 cam, then MTS#20 cam, then a custom cam. Moly rings. Clevite and durabond bearings. Freeze plugs and the regular rebuild stuff.

500 tear down;

Re: Cadillac 500 Build for my 1984 Regal

Did some oiling mods. Tapped the push-plug oiling galleys to 3/8 NPT and plugged them with threaded plugs. Had to get special machined pieces for the front oil galleys, so as to not plug off the main feed. Drain back mods, and general clearancing and polishing from the pickup area all the way to the galleys.

Re: Cadillac 500 Build for my 1984 Regal

Tried my hand at headporting. Got them shiney, but not functinal, and totally destroyed the seats. Then upgraded to larger valves, and had them installed by a pro, with a bit of porting while he was at it. Nothing crazy for CFM, but they move more air than stock.

Re: Cadillac 500 Build for my 1984 Regal

Deburred the hotspots on the pistons to be able to handle the nitrous.














Balanced rotating assembly> Rods and pistons.

Took my old main cap girdle that came off the 472, and revised the design slightly. Made from 1/2" Thk 50W HRS, with counterbored holes. It needed to be tweaked a few times for clearance which I did with a belt sander and a diegrinder and updated the model if I ever choose to do it again. It turned out this was a bit of a painful change to the engine since the main caps are not perfectly level and that needed to be corrected. The oil pick up also needed to be modified slightly to mount to the studs.

Baffled my oil pan. Added 1 kickout to bump the capacity from 5.5 qts to 7 qts. Added a few bungs, for temp, sight plug, and pan mounted dipstick. Tweaked the pick up tube slightly to mount with the girdle. Modified the screen area to add clearance to the bottom of the pan, and a small modification to prevent the pan from being sucked up to the pick up.

Some more of the oil pan and all the parts being zinc plated.

Got my Cylinder Heads back from porting, valve job and assembly. I made one adjustment by drilling a hole in the rear water passage to try andd cool the rear cylinders for a more even operating temperature front to back.

All of the above mods and designs were happening in parallel with machining. The pistons and chambers were CC'd to calculate compression. The block was decked, bored, line honed. The rotating assembly was balanced, and the crank ground and polished. The lifter bores were grooved to oil the cam lobes.