Is there a book or website describing porting on the M head? Are there more than one? I'd be interested to look at whatever's out there. Any favorites?

Thanks,
R.

 

Why do you want to port it?

Whats the application (truck vs car)? Street or strip?

The open-chamber M-heads flow plenty well in stock form.

 

Porting heads without any experience is a 50/50 deal. You might make it better, you might make it worse. Paying a experienced head porter can get expensive and again results may vary. I feel if your not happy with your stock heads, to purchase a set of alloy heads that have been CNC ported. CNC porting provides precise and repeatable flow numbers. Now, someone is going to mention how much alloy heads cost, but by the time you rebuild stock heads with new valves, studs, guide plates and porting etc, you could easily afford a good set of aftermarket heads. I prefer the TFS 195 powerports. and this is why.
1) I own a set
2) heads cost about 1k each complete and ready to run
3) superior flow numbers when compared to 351C 4v heads, yet have the same port size as a 351C 2V head.

just my 2cents

Now if you want to port them just to learn, that's completely different. There are a million threads on the internet about home head porting. I would do some research, watch some youtube videos on it and then start with a set of scrap heads for practice.

 

So I ask a question about something that's going to increase performance for my 6.6 and the I'm asking the wrong questionreplies don't answer the question, they tell me that I'm asking the wrong question or tell me what I'm asking about is unnecessary.
It's just a question, doggone it! Is it so hard to answer if you know something or be still if you don't?

Why port an M cylinder head? Because the head flows 20cfm LESS than a stock Chevy Vortec 906 head at 1/2" lift. And because if the head flows well there's no reason to crutch the poor flowing head with a big camshaft. Because with TMI's pistons the combustion chamber is corrected and now all we need is better flow. If I could take the port from 205cfm at 1/2" lift an increase flow to say 250cfm @ 1/2" lift, it's make an increase in power across the board and the engine would make good power higher into the rpm range. 45cfm is worth roughly 100hp.

Why would I like to use larger diameter pushrods that "I don't need"? Because if I try to cut overlap by using a more aggressive lobe profile there's a better chance of pushrod deflection, and that costs power. It not only costs top end power but it cuts torque across the board.

Home porting is, as was pointed out, a good way to ruin a set of heads. But it's not so difficult to follow directions. In the Mopar world, there have been good articles about how to port small block and big block heads. There were even templates available that one could use to gauge the shape of the bowl as one was grinding. A decent template porting job on a 440 head was worth about 40hp. So I was looking for something similar to Steve Dulcich's articles...Buying aluminum heads at $1000 each is out of the question. I don't want to spend that kind of money on my beater F150. But I have a good die grinder and a lot of time to do my own porting.

Go in Peace,
R.

 

The reason I asked is simple - risk vs reward.

Sure there's a lot of great reasons to port an M-head, but also some downfalls if it doesn't go well or isn't done correctly.

I could definitely see there being an issue with flow and turbulence if not done correctly - for a gain in 40 hp though, and the skills learnt to port a head on your own bench, I would say it's worth a shot.

 

I don't know of any books that deal specifically with a 2 barrel head but there are plenty that deal with the 4 barrel head. One thing to keep in mind is that everybody wants to talk about flow numbers at 1/2 inch lift. Those valves spend twice as much time at .1 or .2 inch lift as they do at .5. So go for it. Clean up the bowls reduce the valve guide boss a little, smooth everything up, maybe port match it. You are bound to gain a little at low lift and that's where you gain some power at driving around town rpm.

 

Like said, a bowl cleanup and port match shouldn't be too hard. Just polish and don't remove too much metal. I would still take them to a pro unless you have a lot more time than money. Serious porting isn't going to help a mild engine and may hurt.

 

I agree with beartracks, and would like to add that you have to consider the RPM range and entire build as a whole. If you want to outflow a vortec head with a 2V cleveland head, then it's not going to take a whole lot of work on that ford head to get there. Knocking down the casting flash, and profiling the valve hump profile to about half of what it is as cast is about all you're going to need. I wouldn't worry about unshrouding & back cutting the valves, cutting the throat relative to the valve size, or gasket matching the head until you're positive it's causing a performance issue.