Hey guys quick question, I am porting a set of c9oe 302 cylinder heads. I have already removed the thermactor humps but I am curious about the valve guide bosses. I saw a post from several years ago that someone removed the boss completely and everyone was saying the port work looked great. Is this okay to do?

 

You never know until you put it on the flow bench but most of the time it is better to narrow and streamline the guide boss and thermactor boss rather than remove it because having some of it in there often it tends to reduce turbulence. The areas to work at are getting the throat the correct size and getting the short side radius blended and laid back the right amount. The same goes for the intake side. The areas immediately at and around the seat are the most important including the valve job.

 

im not particularly referring to whether it increases flow or not, but more if it’s safe to do so? Intuition tells me it will increase flow quite a bit, with it being superheated and super sonic for the most part! Thanks for the reply!

 

There was a nice Ford specific porting website diyporting dot com, but it appears to have been hacked or the domain name registration lapsed and somebody else bought it, but there are still other videos and general porting guides floating the web that cover the basics. WRT these Windsor family heads in general the ports are undersized and the exhaust side is particularly bad, so anything you can do to improve flow is good. The port floor is more important on the intake side, the roof on the exhaust side, but don't completely ignore the other surfaces because it all matters. The main points are bowl smoothing and blending into the port, removing thermactor and streamlining the valve guide boss, and smoothing/contouring other surfaces like the short side radius. I'm not a fan of gasket matching as it can actually produce flow disruption if you end up creating a portion that has a larger cross section than sections upstream or downstream. As with most things you have to keep the big picture in mind, the port cross section should open up uniformly from the valve out, it's counter productive to have bigger port exits in the heads if the intake or exhaust manifold ports are smaller. That is one thing you may want to investigate.. compare the port opening sizes on the intake you plan to use and also look for port misalignment between the intake and head, it wouldn't be unusual to find some ports line up pretty good while others are offset to the front or back.

These are small things but it all helps, professional porters have managed to get surprisingly large flow improvements out of these castings but that takes professional tools like a flow bench and engine dyno, and even with that lots of experimentation.

 

I will keep all this in mind! It’s too bad that website was shut down, David vizzard has some pretty good videos on these cylinder heads that I believe should be sufficient. Thank you guys for your time!

 

Definitely look at David Vizars how to port small ford
heads HE IS the GURU

 

Also sad to lose that website because it showed every change made in the port with flow results so you could see what worked and what did not.

Check out Charles Servidio on YouTube, he does a lot of flow testing on Windsor heads with his porting videos.

 

Wayback is your friend
https://web.archive.org/web/20070901...diyporting.com

 

This vid by David Vizard validates everything I have been taught and done regarding the performance potential of the oem heads…. And that us old timers have known and done for years. IMHO, will have all your answers.