Engine specialists who spend any time sealing up engines. At the same time, it prevents hot spots by eliminating pockets in the chamber surface that allow carbon to build up within the cylinders. In addition, these heads are available with CNC-finished chambers, and for the minimal extra cost, I recommend them. I removed the neck and thermostat housing since I was going to take the head into an engine shop and didn't want it to get lost or banged around.
Therefore, depending on the other pieces of the performance puzzle (camshaft, pistons, intake manifold, etc.), there's really not a one-size-fits-all solution. When I first used the E-Street and Performer series of heads, I consistently heard grumbles that they were somewhat down on performance compared to other brands.
There is another power consideration; most of the aluminum heads have a closed combustion chamber which is far superior to the OEM heads with their open chamber design. BluePrint Engines recommends several different types of header gaskets. Valve seals are an easy enough "on car" repair if one has an air compressor in their garage capable of maintaining at least 120 PSI, any less pressure than that, then there is a good chance the valve will drop down into the cylinder bore.
When the heads came off there was evidence that combustion gases had been getting past the RH gasket at the rear. After snugging the bolts up per sequence chart, I did torquing in three rounds (some only do it in 2)…the idea here being that you want to evenly distribute the pressure as you're bolting your heads down.
We discuss the late '60s and mid '70s style heads like the 441 and 882 castings because they offer decent performance and were produced with sufficient iron. Never mind port-matching the old intake, there wasn't even enough material on the port roofs to permit sealing it up against the 1206 gasket, so Brodix sent out its port-matched HV 1016 dual-plane.
When this condition is combined with an under-valved big-block Chevy, good low-lift flow helps fill a cylinder better toward the end of the induction stroke. When #8 was removed the sleeve came with it. The sleeve is supposed to be secured in the head. In terms of bang-for-the-buck porting, stock heads are the cheapest way to go. However, reconditioning a set Install Heads On A Chevy of Chevy big-block heads is not cheap, and almost anything that is more than about five years old may need a guide and seat job.
First, Pro-Filer is about to launch a brand-new 24-degree casting that uses 2.4-inch intake valves and is said to flow just over 500 cfm. There are various cylinder heads available, and there is even some confusion surrounding what is available. The cylinder head is held on by several bolts and some engines have a sequence for the bolts' removal.
There are mixed feelings on whether or not you should apply a sealer or coating to head gaskets before installing them. Sometimes both materials are used in the construction of the cylinder head gasket. The angle and location of the valves, along with things like cylinder head port size and camshaft profile, factor into how much air a cylinder head flows.
Be careful not to sand too hard in one spot, or you'll make the head or block uneven, causing premature gasket failure or leaks. We use nothing but the Dart adjustable guide plates and ARP rocker studs when we build an engine using these heads, as they allow for perfect alignment of your rockers.
Remove only one pair of studs at a time to prevent any disruption of the Head Gasket. The center two intake attaching bolts on the TBI heads go in at a different angle than on traditional small-block heads. There are two different seal types, one is for the intake valve and one is for the exhaust valve.