Aluminum 320 16-port crossflow head

[Jyrki]

For your information, I have now started a project to design and produce a cast aluminum 16-port crossflow head for the 1936-52 320. It's going to cost a fortune to produce the first head, and probably a small fortune to produce successive heads, so demand will be limited, if non-existent. But the fact that it's possible, justifies it for me. The goal is to have a working head by June 2016. I have found the right partners with the required knowhow, talent, and most importantly, enough interest. More will follow. Hang tight!

[bob k. mando]

wow. very impressive.

will be eagerly awaiting pics.

are you using any of the modern heads as a model for how you're going to lay this out?

[Jenz38]

Respect !! ..
Good luck , especially with the ( at this moment euphoric ?) guys who wanna help you with this project.

[LONG]

what? this is cool. using any common parts? like valves, springs? custom rocker shaft, or use existing? another reason I need a 320.

[Jyrki]

I have found the right partners for this project. A man who worked previously as a researcher in a university, specialized in casting techniques. He now runs a machine shop, and is a hot rodder. He’s going to make the actual design of the head and casting model. Then, I found a cylinder head porting professional, who’s going to design the ports and combustion chamber. He’s probably also going to perform the final machine work on the cast and CNC’d head (install seats, guides + valve job). And finally there’s the foundry, specialized in aluminum casting. For instance, they produce jet propulsion components for Rolls Royce. They also do short production runs. At the moment they’re making an M-series BMW head for a private customer.

We’ll begin by laser scanning my existing 1949 head to find the significant locations, like bolt holes and such. Then we’ll make a blank block, simulating the head, with critical holes, and the porting pro then creates the ports and chambers. Then we’ll scan the block, and create a model of the head, and a casting model. Aluminum shrinks about 1.3% when it cools down, so in a 320 head it means it could be ½” shorter when it comes out of the mold. So a casting model needs to be created as well, that is so much larger.

Initially, our intention is to put the intake ports in place of the spark plugs, and move the plugs in the opposite (exhaust) side. As we are making a head from a clean slate, we don’t want to copy any existing head, but that said, the ports are probably going to look a lot like LS ports. We are going to use components readily available, but don’t want to limit ourselves by doing so. The head will be optimized for my short block, which is overbored to 92 mm with flattop pistons (355 cid). As far as I can tell, the stock valve cover will fit, but not much else.

[Buick Guy]

You're on the right track and have the right resources it appears. Let me know when you're ready for some "destructive" testing. We are pretty good at that. The small bore will limit the valve size and probably be one limiting factor in proper port sizing. Canting the valves could solve some of that but then rockers and pushrods come into play. You've got my address if I can be of any help. [Not that I have any expertise]. Good luck, it sounds like a fun and expensive project. Doug

[Jyrki]

Just to be clear, this won't be a race head, but a street head, providing a wide torque band, off-idle to 5500 rpm. That's not to say we won't leave plenty of room for porting!
We can fit LS1 size valves, about 2.00" and 1.55" by spreading the valves apart a little

[Buick Guy]

Is there any room to add more head bolts? Doug

[bob k. mando]

if you're designing from scratch, you might be interested in looking at Larry Widmer's stuff.

http://www.theoldone.com/articles/The_Soft_Head_1999/

http://www.theoldone.com/articles/default.asp

one of the minor considerations is the supersonic exhaust port. if you try that and decide you don't like it, a properly designed head would have enough meat that you could simply port it out.


the major Widmer design consideration would be the 'exhaust trench'. on a clean sheet design, he recommends that the intake valves be almost vertical over the piston while the exhaust valves are canted away from the intake valves with the plug in the middle of the exh valves.

he talks about forming the Soft Head using shaping of the piston top but that's sub-optimal.



Buick Guy
Canting the valves could solve some of that but then rockers and pushrods come into play.


Jyrki, i take it you're going to stay pushrod?

i would assume there'd be too much deflection in an overhead cam the length of a 320 that was driven from the nose.

[Jyrki]

No, we are not goin to inrease the amount of head bolts.
Yes, we are using pushrods. We are not going to overcomplicate things.