SchmidtMotorWorks wrote:Some guesses are:
Valve pocket to ring groove interference.
beth wrote:The cylinder head has to be lots taller and the valves longer.
SWB wrote:Remember too that the more vertical the valve the smaller the effective size can be made. If you stand them up 90* to the deck then you're stuck with a certain size which can be made to flow effectively. By canting them off in one or better yet, two directions, you can design a much more effective and flow supportive geometry for them to work within. Therefore I think somewhere around 12 degrees one way and whatever (4-5) the other is what is nearly optimal from a total flow standpoint. It's just one big compromise all around, so when you see a lot of the same thing, it's probably because everyone has settled within that range. I don't think the people designing these top level racing heads are idiots or ignoramuses.
I don't think the people designing these top level racing heads are idiots or ignoramuses.
That depends on the rotation point that you unwind the valve angle about.
Engineguy wrote:beth wrote:The cylinder head has to be lots taller and the valves longer.
A valve of 5.45" length, rotated from 18° to vertical only adds 0.27" to head height.
I don't see any reason the valves need to be longer.