A shameless image thread for the enginephiles

[J.A.W.]

Any ideas what the pockets are for between the primary's? Cooling?

Not sure which you are talking about.

the port like holes in between the primaries.

& by "primaries" he actually means the voids between the cyl-head 'exhaust ports' - since in T-F applications..
..the exhaust header-pipe term "primaries" is redundant.. they don't use anything else downstream, like 'collectors'..

[PhillipM]

Any ideas what the pockets are for between the primary's? Cooling?

Intake ports on a sideflow head I assume.

[Maritimer]

Pretry sure it's just for weight removal. Those engines rely on fuel and oil to cool them so everything else is just taking ounces off.

[PhillipM]

They've got a ground finish on them, that's not just for weight removal, something is flowing through there.

[3jawchuck]

They've got a ground finish on them, that's not just for weight removal, something is flowing through there.

Not only that, there are what appear to be bolt holes right next to these mystery holes. I agree with you on it being a sideflow head.

I guess we're wrong: http://www.hotrod.com/articles/ccrp-100 ... el-engine/

I would be curious as to what those bolt holes are for. Brackets or something?

[godlameroso]

They're voids nothing flows there, and you guys say I'm seeing things. That's an Alan Johnson cylinder head, nice billet piece. They go for ~$6,000 USD a pop.

[3jawchuck]

They go for ~$6,000 USD a pop.

Literally in some cases

[PhillipM]

That's a very strange void given the rest of the head is just milled finish - it's been hand ground/ported, and as pointed out, there are bolt holes to fit up a manifold.

[Maritimer]

That's a very strange void given the rest of the head is just milled finish - it's been hand ground/ported, and as pointed out, there are bolt holes to fit up a manifold.

The holes between the pipes here?

[PhillipM]

Yes, maybe it runs into the rocker cover? Or as said it's just lightening holes and someone's fancied them up for show
Makes you wonder what the bolt holes are for though.

[roon]

Probably just for lightweighting. The extra bolt holes might be for different header designs.

[Maritimer]

They don't open to anything so I can't see how they could be anything other than weight removal.

[johnny comelately]

exhaust side, no water cooling .......therefore....

[godlameroso]

That's a very strange void given the rest of the head is just milled finish - it's been hand ground/ported, and as pointed out, there are bolt holes to fit up a manifold.

It's a billet head, every part of it is machined.

[PhillipM]

Yes, but those are not milling cutter marks, they are grinding/honing marks, which you wouldn't normally bother with unless it was a port....or a show head.
Given the die grinder with the abrasive roll in the picture I guess they've just been tidied up for photos.