How much can you mill a SBC head?
How much can you mill a SBC head?
A full point of compression to 9.6:1 would give it around 4% increase. However you could get them milled . 025 without issue other than valvetrain geometry, and use a thin . 018 thickness head gasket.
Is there a way to Mill cylinder heads?
There are a number of ways to accomplish the task. You can buy cylinder heads with small volume chambers already cast or CNC-machined in. You can use dome pistons to effectively reduce the volume of a large combustion chamber or even choose thinner head gaskets. Or you can mill the heads.
What’s the difference between 305 heads and 350 heads?
These heads will port out well, but be aware that 305 heads have smaller valves, so only look for 350 heads unless you’re specifically working on a 305. This will save you the expense of extra machining to put in larger valves.
Do you need to milling the intake manifold?
Keep in mind, milling changes the relationship between the heads and/or block and the intake manifold. Depending on the amount of material removed, the intake may also require milling to compensate. To help you determine the proper milling specifications for factory heads on popular classic V8s, we’ve included the chart below.
What should I know before starting head milling?
Some aftermarket heads are made with extra deck material to accommodate future milling. Remember, these specs apply to flat milling and are intended as general guidelines. Before you start milling, consult with a reputable machine shop that specializes in this type of work and follow their recommendations.
There are a number of ways to accomplish the task. You can buy cylinder heads with small volume chambers already cast or CNC-machined in. You can use dome pistons to effectively reduce the volume of a large combustion chamber or even choose thinner head gaskets. Or you can mill the heads.
What should the stock compression ratio be for 243 / 799 heads?
The stock heads have a combustion chamber volume of 61.15cc, and 243/799 heads have a volume of 64.45cc. My stock compression ratio is 9.5:1. I already know that I need to mill the heads .007″ to lose 1cc of volume. Just to get to stock, I need to mill .023″. Let’s suppose that I want 10.25:1 or 10.5:1. What size combustion chamber do I need?
These heads will port out well, but be aware that 305 heads have smaller valves, so only look for 350 heads unless you’re specifically working on a 305. This will save you the expense of extra machining to put in larger valves.
Some aftermarket heads are made with extra deck material to accommodate future milling. Remember, these specs apply to flat milling and are intended as general guidelines. Before you start milling, consult with a reputable machine shop that specializes in this type of work and follow their recommendations.
