New SBC Manifold with tooling

[af2]

It would be nice to see the plug in the middle of the cylinder between the valves..

[JoePorting]

I was thinking about that. I'll see how it works as is and go from there.

[PRH]

Will the valve pocket requirement in the pistons be so oddball that no other heads could be swapped onto the short block for some back to back testing?

[JoePorting]

This is what a custom 20cc Ross dome piston looks like for these heads. They are 493 grams and are for a 434 cid. Will only be about 10:1, so compression will be an issue. So I'm hoping the airflow will be greater power adder than the loss of compression. I always found compression to be overrated, so we'll see how it does on the dyno.

Piston3.jpg

Piston2.jpg

Piston1.jpg

[PRH]

Got it.

That’s a “no” on the easy head swap.

[JoePorting]

I also think Ross cut the valve relieves too deep, so bringing them up another .100" or so might be worth another 5 CC's.

[GARY C]

Why would one go to this much trouble developing a head and yet discount the decades of chamber development?

At the very least I would have a chamber insert made the would bolt to the roof on the camber and recess the outer plug hole so that it could be screwed into the chamber insert to better secure it or shimmed out when not testing the chamber insert.

Then you could at least test chamber effects on the dyno as opposed to having to build a different head with each change.

[JoePorting]

The printed sand molds are easier. All you do is change your design in Solidworks, send the new design to your pattern maker who makes new cores to place in your current outer core mold, then have the printed sand mold company make the new sand molds, have the foundry cast them, then send it to your CNC guy who cuts the new heads.

[GARY C]

The printed sand molds are easier. All you do is change your design in Solidworks, send the new design to your pattern maker who makes new cores to place in your current outer core mold, then have the printed sand mold company make the new sand molds, have the foundry cast them, then send it to your CNC guy who cuts the new heads.

Yes but not something you can do on dyno day for a back to back comparison, although my idea would require changing to a standard flat top in relation to a custom dome piston.

[GARY C]

If you are doing this for your own use then do what you want but if you plan to produce this and sell it to the public then you should take note of the response you get about the chamber.
Regardless of your power numbers I would be willing to say that most possible buyers will look at the chamber and pass on the purchase.. You should contact Jon Kaase to get an idea of what you will have to do to move a new head on todays market.

[swampbuggy]

Joe, how big do you think you're combustion chamber will end up in CC's ? MARK H.

[JoePorting]

It's about 90 CC's.

[SchmidtMotorWorks]

The offset mass of that dome looks like it will create a rocking force.

You are on the same discovery path as the 348 409 engines were, only they were primarily intended for low rpm truck use.

IIRC a 409 piston was capable of 6000 for only a short time.

[Warp Speed]

The offset mass of that dome looks like it will create a rocking force.

You are on the same discovery path as the 348 409 engines were, only they were primarily intended for low rpm truck use.

IIRC a 409 piston was capable of 6000 for only a short time.

Ya, unfortunately there is a lot of bad stemming from the poor chamber design.

[JoePorting]

I thought Ross could have pulled out another 20 or 30 grams from CNC'ing the back side of the dome. Maybe something to bring up next time.