Different chamber styles & timing / octane reqs

[BradH]

I think your splittling hairs and over thinking this deal...

Wouldn't be the first time...

[Carnut1]

Plug sides of "A" and "B" chambers essentially the same;.the quench side is where 98% of the differences are. Edelbrock revised the quench pads on those heads and reduced the chamber volume with the later "A" casting.

"B" has the larger chamber, larger intake runner volume, and smaller quench pad.

I like the quench pad deshrouding better on "B" heads. My mistake. Interesting that Edelbrock changed that.

[Carnut1]

PRH_chamber1_sm.jpg

Goofed the last post up. This chamber quench side I actually like more. Does it run better or flow better? I do not know. It is interesting that Edelbrock opened up that side and reduced quench volume.

[BradH]

Plug sides of "A" and "B" chambers essentially the same;.the quench side is where 98% of the differences are. Edelbrock revised the quench pads on those heads and reduced the chamber volume with the later "A" casting.

"B" has the larger chamber, larger intake runner volume, and smaller quench pad.

I like the quench pad deshrouding better on "B" heads. My mistake. Interesting that Edelbrock changed that.

Deshrouded better, but less conducive to pressure recovery. I've been wondering how much the "A" chamber would increase in volume if I pulled back just the exhaust side of the quench pad... would look more like an LS3 chamber.

[BradH]

PRH_chamber1_sm.jpg

Goofed the last post up. This chamber quench side I actually like more. Does it run better or flow better? I do not know. It is interesting that Edelbrock opened up that side and reduced quench volume.

If you compare the quench pads of the two different chambers by referencing where the pad stops with respect to the bolt holes seen below the chambers, you'll see how much the quench was increased with the change to the smaller "A" chamber.

[Carnut1]

PRH_chamber1_sm.jpg

Goofed the last post up. This chamber quench side I actually like more. Does it run better or flow better? I do not know. It is interesting that Edelbrock opened up that side and reduced quench volume.

If you compare the quench pads of the two different chambers by referencing where the pad stops with respect to the bolt holes seen below the chambers, you'll see how much the quench was increased with the change to the smaller "A" chamber.

Looks to me like the old chamber has more quench. Snap a pic with a caliper to clarify. Thanks, Charlie

[Mummert]

Big block dodges have the chamber pushed all the way to the exhaust side of the bore. Stability of SSR will be paramount to keep the swirl from getting out of control on that head. The chamber with the most definition behind the valves will help SSR stability. I would pay attention to valve pocket shaping, make them a little bigger to match chamber shape .

[Mummert]

double post