Cross section photos of high performance engine heads

[cyanide]

Hi everyone.
I'm a hobbyist who builds Hondas for fun and beer money.

I am shooting for around 200 whp NA from a 1.5L Honda motor. As per my experiences, the secret of an engine's power always lies in the head and its ancillaries like the intake and exhaust. I have the intake and exhaust covered. Same with the camshaft. My next job is to port the stock factory head, without a flowbench.

I have seen a couple of cross-section photos of engine heads of superbikes and of an F1 engine (Toyota). They always have the intake port literally angling straight and shooting the back of the valve to conserve the charge velocity. The exhaust port is of a similar shape, but has a shorter radius with a bit more curve.

I have tried searching for lots of pictures of such cross section profiles but have always come short. The photos on gurneyflap.com aren't really useful in that respect. If anyone can help out and post some nice pictures, I will be very grateful.

Posting one picture as an example.

[marcush.]

you know that one ?
www.theoldone.com

[cyanide]

Yes, I know Larry's work. A magician will never explain his tricks. He has posted tips on the website, but it will never cover the kind of radical porting that I am interested in.

I am lucky to work under a great guru. Together, we've hit over 185 whp on a similar engine. However, I have not seen the head work done on that engine. My work was limited to sourcing the best parts, importing them to my country, working on the intake system and mapping the ECU.

I would not ask him what work he did on the head as I respect his right to keep secrets. I love to experiment, so I do not mind wasting a few months on a head to make it just perfect.

The motor will be running about 12:1 static CR on 91 octane pump fuel.

Thank you for the reply

Edit: I know it might sound retarded that I worked on the intake system and yet didn't see the head work... I designed the individual throttle body system, syncing the airflow across all 4, deciding the runner lengths and diameters, etc. I was given the specifications by email and I designed the rest in CAD accordingly. Just thought I'd explain.

[cyanide]

Nobody?

[mep]

Ok Ok
Is something like this also ok?

1992 Honda RA122 F-1 V12 Engine - McLaren MP46B & MP47A F1 Formula One


Audi W12 6.0


Porsche 911 Motor


Boxster-Engine


Mercedes Benz 500 Ilmor Motor


Chevrolette Ilmor Motor




Feel free to show what you have found so far.

[cyanide]

Wow, thanks. Sorry I've been busy the past few days researching on headers.

These cutouts don't really show the intake/exhaust port paths. I will post my own contributions in a few hours. Thank you for posting

[Caito]

I must say that doing a flowbench is not complicated at all if you know basic electronics. If you don't know basic electronics you can just use the old water pipe and measure height.


A couple of pressure sensors, a cheap data logger(or build it yourself) and a vacuum pump.(some people even use a vacuum cleaner).


That might help you a lot.

[cyanide]

I will be devising some kind of a flow measurement method, yes. Just that I do not own or have access to a real flowbench that costs thousands of dollars.

Anyways, some of my own contribution. Some of it isn't exactly a cross-section cutout, but shows the kind of ports that I am talking about.















If anyone has some good stuff, please post. Thanks.

[olefud]

I'm a bit stale on this but, if you have sample good ports, fill them with castable rubber and form positives of the negative port -a little lube helps removal. Then cut the casting at right angles to figure the X-sections along the port. If you have access to a good balance, just trace the X-section on paper, cut out and weigh. Counting squares also works. Once you know the X-sectional areas along the port axis, you're baselined to start trying things.