Technical head info for motor yoda's!

[Allforspeed]

i found a bunch of old head info articles on this site that are super interesting if you've got the time, i thought the head swirl information on the intake port part here: http://www.theoldone.com/articles/The_Soft_Head_1999/

were interesting, i remember on the mouse page, he was talking about digging behind the intake valve on an E7TE head similar to the design of a GT40P head, and increasing flow, sounds like this is what mouse found through trial and error, looks like the GT40P head is a pretty classic SOFT head

bunch of articles, maybe you read them but any comments from the head porting/motor building jedi's out there?? i thought this stuff was super interesting...


here is the site, articles at the bottom udner magazine articles.

http://www.theoldone.com/articles/

 

[Allforspeed]

if anyone has ever been inside of a 911 3.0 SC motor you can see the piston definately has a bulge on the intake valve side, i guess to push the charge towards the exhaust side, seems just like what they are explaining here.

 

[Allforspeed]

here is something interesting also, i always heard of porting the exhaust side smaller than the header, leaving a little step, but doing the intake side also?? i never heard of that before...


Regardless of application, grind the port in the header flange slightly
larger than the ehhaust port exiting the head. On the intake side, always
make sure that the inlet port in the head is slightly larger than the port
exit of the intake manifold. We're not talking much, but assuming that
flow will be traveling backwards on each side of the engine, the small step
you create with the mismatch will prevent the reverse flow from having
such an easy time, because it ain't worth **** for power...little things
(T.O.O.). If you have the money take the headers (or ship them)to either
JetHot or HTP and have them coated inside and out. Not only will they clean
the crap out of the headers, but the coating will retain heat, resulting
in better flow. That's simply one reason we like mild steel with coatings
over stainless. Applications where we MUST use stainless, we coat them
inside and out as well.

 

[Allforspeed]

i wonder how much of this stuff can be applied to porting E7TE heads?

 

[tmoss]

Nice find! Good info there. Now your not the only one in this thread.

 

[Allforspeed]

thanks tmoss!!! now i'm not so lonely lol

i just put this stuff up more for people to read if they're interested than to make a discussion or anything, i thought the whole "soft head" idea was really interesting thing that i've never heard before.