5752 113

Hi, I have a set of these (ECR-D) that have small valve stems (11/32) the one in the picture is the larger (7/16 exhaust) 

Cliff

Those ECR's also have bigger diameter valve stems and guides should be remade for stainless or titanium race valves .

 Seppo from Järvenpää, Finland
www.hollowheads.net (just click the hole in the head to proceed)

Back when I had an Olds Cutlass with the scruby 350 I bought a book by David Vizard on cylinder head design and theory. When he did the dyno tests on cylinder heads he found that on the scruby 350 that the "closed chamber" design ( like the ECZ G ) bath tub style was better by up to 25 HP over the "open chamber" ( like the ECR ) heads. So the take away for me is unless you super-charge or turbo your Yblock the closed chamber heads are better. Pete

Notice how the ECR-D's have barely any step from the surface to the bottom of the combustion chamber, I have a set of those I beleive or they are ECR-something and always thought they must be a high compression head.

55 Vicky & customline

58 Rack Dump, 55 F350 yard truck, 57 F100

59 & 61 P 400's, 58 F100 custom cab, 69 F100, 79 F150, 82 F600 ramp truck, 90 mustang conv 7 up, 94 Mustang, Should I continue?

ECR-D these are the heads I like the best (Supercharged Motors)

471

113

The last one is RUST-Y, the most common head.
Actually, Maybe EBU.



Lawrenceville, GA

As we have several different combustion chamber shapes in our engines, why don't we just put up a comparison picture thread here? I have couple of pics to start with...
ECL-C


ECZ-C



ECZ-G




C0AE



Can't remember which this is (have to check it out next time I crawl to garage)



I think I had ECRs once too, but those were scrap, so I throw them away before shooting any pics...

 Seppo from Järvenpää, Finland
www.hollowheads.net (just click the hole in the head to proceed)