Point of interest, cool heads
 

We found these heads in a 2.7 race engine sent to us as a core.
The heads have been welded and shaped to create a rather unique combustion chamber.
The chamber measure 54 cc. With a set of 2.7 RS pistons (relatively flat top 8.5:1) and a 70.4 mm crank this configuration makes 11.1 to 1 compression. With a 66 mm crank and the same pistons we get right around 10.6: 1.
Because of the squish chamber configuration the engine should be less likely to detonate hence the need for only one plug.
Do they flow? who knows, but the concept seems to be very cool indeed.
http://forums.pelicanparts.com/uploa...1211469375.jpg
http://forums.pelicanparts.com/uploa...1211469926.jpg
http://forums.pelicanparts.com/uploa...1211469947.jpg
http://forums.pelicanparts.com/uploa...1211479217.jpg
http://forums.pelicanparts.com/uploa...1211479233.jpg
http://forums.pelicanparts.com/uploa...1211479262.jpg

Looks like they were trying to make a peanut chamber out of a hemi. Interesting idea, done it on a compact wedge myself, but never like that! Nice find!

Amazing Henry, I can only imagine the amount of work that must have gone into those. . . the casting number is 911 104 302 0R, which makes them 1972 heads (casting date looks like 3-71). Welding that up and then machining it must have been an exercise in patience. . . and metallurgy, certainly.

Thanks for contributing, great stuff!

Similar concept to these heads (albeit enforced by the rule book)

http://forums.pelicanparts.com/porsche-911-used-parts-sale-wanted/276664-fs-set-6-factory-962-racing-heads.html?highlight=IMSA+head

Regards
John

Very cool indeed.

Kinda like seeking out the Chevy closed chamber heads for use on an open chambered engine.

Those really do not look as if they have been welded and if they were whoever did it, did a pretty poor job just by the amount of porosity in the added material. Pretty much what Porsche should have done from the beginning, nothing crazy really, squish, tumble, pent roof, no matter, the hemi is dead. They look pretty similar to some early porsche twin turbo race heads I have seen.

The fact is, they are welded and by my way of thinking, whoever did this fabrication did an exceptional job. The magnitude of work required was enormous.
The execution [considering the material he had to work with (cast aluminum) and the environment it had to survive in] was more than adequate and in fact beyond the requirements of most cylinder head builders.

As for being "pretty similar to some early porsche twin turbo race heads", the only head that even comes close is the IMSA, single plug, single turbo 962.
The squish chamber head was an attempt to control detonation in a single plug race engine and was generally thought to be quite effective.

Please post pictures of the other Porsche heads that you have seen that resemble these. Curious mind want to know.



http://forums.pelicanparts.com/uploa...1211561222.jpg

Paul Weir was/is trying to sell a set of these.

http://forums.pelicanparts.com/porsche-911-used-parts-sale-wanted/276664-fs-set-6-factory-962-racing-heads.html

I am with you on this Henry. I have seen some of the best and of course, some of the worst "mods" of this type. I think, judging by the pics only, that the modification is very professional. I don't see the "porosity". What I do see is normal surface degradation which obviously happens over time in a race application as well as stock.
Good pics.
Would like to flow one...

You got it. One head is on it's way to you via UPS.
Let us know what you think.



BTW: welcome to the board.

These heads seem to be turning up all over the place.

http://www.early911sregistry.org/forum/showthread.php?t=20850

Trust me I would love to show people half the pictures I have but its either current racecar stuff or the owner or builder or things doesnt want me posting pictures of their cool stuff. Ive got plenty of pictures of Cosworth dfv's, dfx's, some early and mid 90's f1 motors, rally car stuff, imsa, can-am, current nascar and on and on. One day years from now I will have more then enough to throw together a book with descriptions, I wish I could show you all now though.

I get it. You'd show me but then you'd have to kill me. Yeh right :)

After being around the Indy grid for many years I learnd "if you can take a picture, it's no secret'"

a dare here ??... not trying to start anything... a picture tells a thousand words... if you can read or see it, IT IS HiSTORY as Henry says it,,, if you can take or sneak a pic of it, it is history/common knowledge... so show us what you have, please... inquiring minds want to know!!
Bob

i smell bull****

Those heads are unlike any Porsche heads I've ever seen. I look forward to hearing how well the flow.
Flow or not the chamber looks like a definite improvement over the stock hemi design.
Cool stuff, Henry !!!

It would we interesting to know what the CR benefits are, both single and twin plug, if any at all.

I was about to mention that Ed Mayo's shop in Euless, TX did some heads like that on "the old brown car" that used to run out of that shop. I then looked at the early s forum link that someone above posted and sure enough Ed chimed in over there.

I remember seeing the car that had these type of heads run at TWS and it ran extremely well with single plug ignition.

Smell all the so called bull all you want but I was allowed to take the pictures with the understanding that I would never post them, at least not for a few years. From a little shop in northern CA to another almost unmarked shop in the santa ana area that used to be called a dial or something like that (you figure it out) I have friends who work there and I got some sneak peaks. Ever wonder what happened with those Brumo's DP motors that kept blowing up? They were abnormally large in porsche terms.

i'm just saying: believe none of what you hear, and 1/2 of what you see.