MOFOCO Cylinder Heads

[Duner]

Anyone have any experience with MoFoCo cylinder heads? Are they a good quality product or are any of the other products better?

I was going to replace my single ports with a set of dual ports and these seem to be well priced in the market.

So if anyone has experience with this product I would like to know before I commit the cash.

[Aquabuggy]

Had a set of the 041 MoFoCo heads on the orange buggy, they worked fine for me.

[Vee Dub Nut]

I have Mofoco 042 heads on my sedan... they are about the only thing I can say good about Mofoco though

I had a host of problems with my engine kit from them, and a huge lack of customer service/support.. and to top it off, the engine tanked pretty early.

I reused the case and the heads when we rebuilt the engine and its been fine since. I can't honestly say anything real bad about the heads, but from my past experience I would recommend looking elsewhere. There are tons of reputable shops that sells heads that are just as good and have a much better reputation..

Oh yea.. when we did rebuild the engine I noticed the castings had cracked between the two valves on all of the combustion chambers. They claimed this was normal for big valve heads.. and to their credit we reinstalled them and they have been fine.. take it for what its worth..

[David O']

What kind of heads are you looking for and what size is the engine?

[Duner]

I was looking at using the 041's on mild 1641 engine. As a side note I don't think that I have ever seen a stock VW head that did not crack large or small valves, german, mexican, or brazilian manufacture. I have a pair of well used cracked dual ports now and I'm pretty sure when I remove the single ports off my 1970 1500 they will be cracked as well. I was just hoping that some of these usa made heads were better than the stock type of casting.

[David O']

041 heads on a 1641 will not have the same pick up that the stock heads do. the original 041 head was the brazilian answer to the addition of ethonal to the gasoline mixture.
The intakes of the 041 head will end up with with really gunked up intake valves, due to the slow air speed in the intake port. (I know this is going to start something). The heads cracking is not due to the material or the size of the valves, but to the temperature of the heads when they are running. If you hemi cut the heads , the compression will drop (and it is at any amount that you want to have) and the heads won't crack.

[Vee Dub Nut]

that interesting..

I had never saw a stock set of heads that were cracked before. That's why I was so surprised when we pulled my Mofoco heads.

David.. what is the physical difference between the original 041 and the Brazilian castings for the ethanol blended cars?

[David O']

041 heads have an intake valve size that is 15 per cent larger so air and fuel into the engine to make the same power. It throws the balance in valve ratio off. But unless you have the intake and the end castings to match, the velocity of the air in the intakes is too slow to carry all of the fuel into the chamber.

[Vee Dub Nut]

Interesting..

So I guess that this issue with low intake velocities with the stock manifold could be prevented with a Brazilian intake and end castings, or larger dual carbs with manifolds that are ported to match?

[David O']

Somewhat, but the velocity is based on the piston speed and the displacement of the motor.......1900cc wouldn't allow the intake valves to get gunked up.
If you have 40mm intakes, you need 35.5mm exhausts to keep the valve ratios right.

[Vee Dub Nut]

Yea I wondered if it will still be a lot for a 1641

Could always build a stout bottom end and rev the mess out of it

[David O']

Well, more than engine speed, it is the ratio of the valve size to the piston size that determines the port speed of the air. Unfortunatley, it gets real complicated, real quick. You might consider buying the Gene Berg books on engines, as he forgot more about the VW than most people will EVER know! I know, I got to meet him once, and that was an experience!