Cylinder head dyno shoot out

PRH said
No one asked, but I’ll offer up my .02 anyway….

I’d use some off the shelf “affordable” forged piston that put the compression in the 10.-10.5cr range with a 65cc head(I wouldn’t argue against flat tops).
Shoot for “0” deck, and then whatever the CR ends up with the various heads, “iiwii”.

I’d test all the Ede/SM variants as the first phase, then move on to the “others”.
This would allow the valvetrain to be reused for all of the heads in phase one.

Personally, I don’t see the point in testing more than one set of “unported ootb” SM variants.
Use the ones from SM in true ootb form, then a set with the seats done and a quick bowl blend…….then whatever else tickles your fancy.
I do think it would be “interesting” to see how truly “ootb” Ede’s would compare to truly “ootb” SM’s……..I just don’t know that it’s worth doing that test to find out.
I guess you couldn’t really answer that question until the results were in.
If one was significantly better, it’s worth it. If they’re about the same, probably not.

Cam in the mid/hi-250’s, low .600’s lift, 108 lsa, 1.5 rockers.
Something that should easily make 550hp with the ported heads and a reworked single plane for a hot street/strip type build.

I believe the HS made Mancini rockers will fit any of those heads without any spring interference issues.

Since no one asked I’ll throw my .02 in with PRH.

IMO the best plan is to first figure out the “why” the testing is being done. Is the testing to find the best street/strip head package (and then you have to define what that “best” is) or is the testing for the best overall torque and power curves, looking at an arbitrary converter stall number?

Once you define the “why” of the testing you can outline the types of test(s) to be done.

Then you have to decide if minor differences in chamber shapes and such will require testing to develop the correct timing curves for the different chambers etc.

Are you going to do lash loops on every head or just optimize the “A” head and run the same lash on every other head?

Are you going to go back to the “A” head at the end of all the testing to verify the numbers have remained consistent across all the testing?

How many pulls on each head?

Do different heads respond to different intake manifolds? If you test for that then you’ll be making probably a hundred pulls or more depending on how many heads are in the test.

Pushrod length affects rocker geometry and lift. If there are different stand heights and locations and the geometry is different how do you know how much of the gain (or loss) is attributed to the head or the change in geometry/lift?

You can really end up in the weeds with this kind of testing. The more heads the more testing.

I agree with PRH about just one chinesium casting. Probably the Speed Master as the base head and then test the TF and the Bloomer head against that head.

I’m excited.