Our complete cylinder head assemblies include the following machining operations and superior quality parts:
Valves: Our complete heads are assembled with 11/32″ stainless steel valves. Typically, we use REV, Ferrea 6000 series or Manley Race Master valves. For roller cam applications, the valves are upgraded to the Ferrea Competition Plus or Manley Severe Duty series. Hollow stem, titanium or 5/16″ stem valves can be used to reduce the valve train weight.
A typical stainless 11/32″, 1.94″ intake valve weights 114 grams. The same valve in the hollow stem design is 95 grams. A titanium valve is 79 grams. For several reasons, the hollow stem and titanium valves with 11/32″ stems are a more popular option than the 5/16″ valves.
Valve Springs: We use Isky, Manley or PAC springs. The springs are matched to your camshaft specifications and track rules. For roller cam application, the springs are typically upgraded to the Isky 9900 series springs.
Retainers and Valve Locks: Machined steel retainers and valve locks are standard equipment on our complete heads. We use retainers and locks from Isky, Manley and Comp. Cams, along with some of our own designs. Valve spring retainer weight is critical. A typical steel retainer for a 1.250″ spring weighs about 21 grams. Our steel retainer, #602RA, weighs 19 grams. Most of the “cheap” retainers on the market are very heavy. One retainer sold by a major cam company weight 26 grams! Light weight tool steel and titanium retainers are available as an upgrade. Ferrea makes a 15 gram tool steel retainer for the 1.250″ springs; titanium retainers for the same spring weigh just 12 grams.
Rocker Studs, Guide Plates and Spring Locators: We use ARP rocker arm studs, Comp. Cam or Manley guide plates and hardened spring locators on all our heads.
Cylinder Head Prep Work and Machining
Pressure Testing: Before we to anything, all of our heads are pressure tested. You might ask, “Why do new heads have to be pressure tested?”. The answer is because 11% of the brand new castings we have tested over the past few years leak right out of the box. This holds true for all the manufactures. So, we pressure test all heads before we work on them.
Valve Guides and Valve Job: Most new cylinder heads come from the factory with improper valve guide clearance. Some heads, like the Chevy ‘602 Vortec crate heads, are too tight. Others have excessive valve guide clearance. It is common for us to install new guides in brand new heads because the “out of the box” guide clearance is over .003″. Also, some heads like the Engine Quest CH350I heads tend to ware-out the stock, cast iron guides very quickly; So, in this case, we install bronze guide liners. We use a variety of valve guides including a custom steel guide, solid bronze and thin wall liners. The style of cylinder head and its intended use determine which type valve guide we use. The valve guides are sized for proper clearance using carbide reamers and a Sunnen diamond honing system. After the guides are honed to proper size, the heads receive a performance, flow bench developed valve job.
Machining Spring Seats: As part of the proper valve spring setup to insure maximum spring life and correct spring pressure, hardened spring locators are installed on most heads. Spring locators will keep the spring more stable and help transfer heat to the water jacket. The spring pockets are accurately machined to accept the locator.
Surfacing: Complete heads will be surfaced with a flat cut for your compression ratio requirements and rules. Depending on how much material was removed, the intake manifold gasket surface may also be machined. Angle milling is an extra cost option on complete heads. On angle milled heads we also correct the intake manifold surface, straighten and spot face the head bolt holes. Digital Buret is used to check the chamber sizes.
Pushrod Holes: If you rules allow the use of screw-in studs and guide plates the pushrod holes will be opened on heads that have not had this done from the factory.
Fitting your intake manifold to cylinder heads: Properly “fitting” the intake manifold to the heads is one of the final operations. The finished heads are bolted to a block and your intake manifold installed. To get the intake manifold to fit correctly, especially with angle milled heads, we may have to open the intake manifold bolt holes, machine the intake manifold gasket surface and/or machine the end rails on the manifold. We not only have just about every small block Chevy intake gasket on the market in stock but also have a custom designs that are not available from the large manufactures. Our custom gaskets include 1/8″ thick gaskets for both the Vortec Bow Tie and Fel Pro 1205 size. Once the intake manifold mechanically fits the heads, the manifold is checked and adjusted for proper intake port alignment. The bottom line is this: When you get your heads and intake manifold, they fit.
Assembly: After all the machining operations are completed, complete heads are deburred, washed and assembled. During assembly the valve guides are coated with assembly lube, spring heights set and valve seals installed. Complete heads are placed in zip lock bags and shipped in our custom head boxes. Don’t worry, our name is not on the outside of any of our shipping boxes.
Accurate Record Keeping: Accurate records are maintained on each set of heads, bare and complete, for future reference. Your receipt will have the part numbers for the parts we installed or supplied with the heads. We often receive calls concerning heads that have been in service since the 1980’s. With our system the records can be quickly referenced.
We don’t tell nobody anything: We will only discuss the work performed to the heads with the permission of the person who purchased them. Customers’ names and their purchases will never be discussed with anyone except the original owner.
There you have it. A complete set of Brzezinski Racing cylinder heads. They are an investment you will have for many years, and hopefully, many wins.