Cylinder Heads

Premium Re-manufactured Stock Heads

Specify 76cc, 120cc, or 425 heads. Shot-tumbled, magnafluxed, surfaced as needed, and assembled. No port work. Bronze guide-liners are installed, and seats are cut and hand lapped. Stock heads are assembled using stock size replacement valves (2.00” induction hardened intake/ 1.62” stainless exhaust), OE size performance valve springs (Stage I), Chromoly retainers, and hardened valve locks.

Super/Street Steel Heads

Specify 76cc, 120cc, or 425 heads. Shot-tumbled, magnafluxed, surfaced, and assembled. Intake and exhaust ports are matched to our premium gaskets. Pushrod walls on the intake side are moved back. Ports are smoothed, blended, and polished (the last 1½”). Bronze guide-liners are installed, and three angle seats are cut and hand lapped. Super/Street heads are assembled using oversize 21-4N stainless valves (2.19/1.90 for 76cc, 2.11/1.77 for 120cc and 425 heads), special spring shims, performance valve springs (single w/ damper), Chromoly retainers, and hardened valve locks. Valves are not “back cut” to ensure maximum longevity.

PRO/Street Steel Heads

Premium Overhaul KitPremium Overhaul Kit

Specify 76cc, 120cc, or 425 heads. See ‘Super Street’ Heads above. With more port work and reworked combustion chambers, these heads are the best street performance value on the market. They have no trouble supporting a real 600+ HP on pump gas, while also being the best heads available for maximizing bottom end torque.

PRO/Comp Heads

76cc or 120cc Heads. As above, PRO/Comp cylinder heads also feature fully worked ports, radiused guides, your choice of 2.11″ (120cc heds only), 2.19″, or 2.25″ intake valves, Chromoly spring cups, dual valve springs, lightweight Chromoly retainers, and hardened valve locks. This is the very same head package (even the same valves) found on the Spectre Speedliner 484 CID FIA engine, running over 415 MPH on gasoline. While the standard package is capable of amazing feats of performance, we do offer (and recommend) upgrades to this package for certain applications, such as Inconel valves for turbocharged applications (the stainless valves are not bulletproof under boost), titanium valves and retainers for high RPM roller cam setups, etc.

Boogie Man Aluminum Heads

The long awaited and highly anticipated “Boogie-Man” cylinder heads are now available. This is the next step in the “Boogie-Man” line. Using an American made casting, cnc machining, and a top-of-the-line seat and guide machine, we have the absolute best cylinder head for a high performance 472 or 500 Cadillac, on the market today. They have 70cc combustion chamber chambers (adds about 1/2 a point of CR over 76cc iron heads), and include 2.25″ / 1.8″ valves (the same high-grade stainless steel and production methods used for our iron head valves). These heads have been used on numerous applications from daily drivers to full race applications, and they weigh in at 32 Lbs. (vs. the stock iron head’s average weight of 62 Lbs.) per head.

The unique high velocity port design allows for some truly impressive flow numbers at high and low valve lift. Out of the box these heads are flowing a ‘head turning’ 402 cfm, while still allowing strong low lift flow as well. They are assembled with the best seats and bronze guides you can buy. They come standard with a multi-angle valve job. There are several valve options, including the standard package SS valves, and optional SS, Titanium, or Inconel valves in several sizes, to finish the heads for any performance application or level you desire. We have completely redesigned the ports and combustion chamber to increase power.

The most unique thing about these cylinder heads is the raised and extended ports, that will still allow a stock intake to bolt up. We spent countless man hours to get this part right. Even though we have produced a part capable of extreme high performance, we wanted it to be useful on almost any application. Note – this will raise the intake about one inch, which means even a stock intake, with these heads, will not fit under a flat Eldo hood, or any other application where the stock heads and the intake you are using leave you with less than an inch to spare. The exhaust ports have also been raised, as well as the flange being redesigned to use more bolts for a better seal. Laser-cut header flanges are available, but there are no off-the-shelf headers currently available.
Now let’s take a look at the flow numbers:

Valve Lift Intake Flow
.200″ 171 cfm
.300″ 233 cfm
.400″ 296 cfm
.500″ 345 cfm
.600″ 376 cfm
.700″ 391 cfm
.800″ 398 cfm
.850″ 402 cfm

We have produced engines with a very streetable 500 hp and N\A full race engines over 800 hp using these heads. These cylinder heads are the crowning jewel of the top end package we offer for any serious performance 472 or 500 Cadillac engine. We have done the research, finished the development and made it easy for you to get every drop of performance out of your Cadillac.

Stock Replacement Aluminum Heads

These are the evolved version of the old Bulldog aluminum heads. They have 76cc combustion chambers and include 2.19 / 1.90 stainless valves, and weigh in at 38 Lbs. per head, vs 62 Lbs. per head for your average iron head.Performance wise, they fall in between our Pro Street and Pro Comp 76cc iron heads. These are a good choice for medium performance levels, where saving weight is more important than bottom end torque, such as lightweight drag cars and gearbox airboats, but you aren’t going for maximum power. CNC porting is available, if you need more airflow, but don’t have the room for the extra inch of intake height the Boogie Man heads will give you, but they will still not be in the quite same league for power output.

Cylinder Head Fasteners

Cylinder Head Bolts New stock style cylinder head bolts
Head Stud Kit ARP 4130 Chromoly with nuts and washers

Cylinder Head Core Charges

Core charges vary, depending on the casting numbers. Cad Company does not pay inbound freight on cores in most cases. We do accept different casting numbers than the heads you are purchasing as cores, with the exception that we do not accept 425 head cores for 472 / 500 heads. You may ship your cores ahead of time to avoid paying the core charge in the first place, or you may ship them later for a refund of the core charge. The maximum core charge refund you will receive is the amount designated for the heads you are purchasing. Cores returned more than 1 year after the initial purchase of the heads will be refunded 75% of the core charge due.There is no core charge for aluminum heads, but we will still take your old iron 472 / 500 head cores for 1/2 of the listed core values.
We do not pay inbound shipping on cores.
76cc Head Cores  250, 950, and 902 castings
120cc Head Cores 493 and 552 castings
425 Head Cores 423 castings