Primers on Cylinder Head / Combustion Chamber Design

[kradicke]

Are there any decent, thorougly explained guides to combustion chamber and cylinder head design?

The recent discussion on the Chrysler Viper and 2.2L heads was very interesting, but obviously (to me), it is difficult to carry over recommendations for one head to another head of different manufacturer, design, and shape.

Secondly, how would you go about adding material to a cast iron combustion chamber? I've read enough information on quench/squish area to know that it is beneficial, but how do you go about building this extra material into a head that never was intended for this type of development? (I read what Larry said about heat distortion on the aluminium heads, does the same hold true then for adding material to then for cast iron?)

Thanks,

Kai

 

[NickB]

I've welded a few cast iron manifolds, and i can say that it's not very easy to do without cracking, and they do distort a bit. Preheating and post cooling are very important when welding cast iron. The whole piece has to be a few hundred degrees to keep distortion down and prevent cracking. A very knowledgeable welder i know said to pack the part in a large drum full of vermiculite (something used in potting plants, it's an excellent insulator)and let it cool off for a day or two. (he said it often does take a day or two to cool this way)

The head will most likely require machining to get the seats and everything lined up again properly.

 

[MaxRaceSoftware]

i have an old friend "Joe Helmer" who lives
in Jefferson , LA (close to New Orleans)

he was a dental assistant , and decided he wanted to weld
cast-iron heads

he went to Al Mathon's HeadMaster , studied technique
for a couple of years, and bought the entire operation,
maxhine shop equipment abd all ,
moved entire operation to LA

hes retired now , and business is long closed ,
but he got to very good at welding , with very little
distortion , no surface blemishes, very excellent quality
most times you could just mill .006" off surface to get it true .

you don't REHEAT treat cast-iron after welding like alum.

when Joe finished welding up heads, the heads appeared
to remain the same hardness ...with other guys , their welding left the heads much harder to where you sometimes had to use a wet-surfacer to mill .

i think Pete Incando (? spelling) is back welding heads
somewhere around CA , AZ area ??

Larry Meaux (meauxracing@mindspring.com)
Meaux Racing Heads - MaxRace Software
ET_Analyst for DragRacers

http://www.mindspring.com/~meauxracing/

Support Israel - Genesis 12:3

 

[RacerRick]

I have had success using Eutectic Castolin rod.# xyron 2233 It is very expensive but you can weld ports, chamber, etc I shot blast the area, then grind it with a carbide burr, pre heat to at least 600 in a oven. Weld very small amounts at a time and peen and weld and peen and grind and weld and peen etc..... You can't weld a big long bead or it will crack. lots of little beads under 1/2" long seems to work the best for me. Some exhuast ports and manifolds that have been expose to leaded fuel won't weld worth a darn.

 

[NickB]

I've run into the same problem with contamination when welding quite a few times. Used intercoolers are a real pain, they often have an oil film that boils off and makes it nearly impossible to weld until all the oil is burned out. Silicone makes a huge mess too.

 

[MaxRaceSoftware]

Kai ,

try searching thru SAE papers in your College Library
near you !!

you should find a lot of info in SAE papers on combustion chambers Larry Meaux (meauxracing@mindspring.com)
Meaux Racing Heads - MaxRace Software
ET_Analyst for DragRacers

http://www.mindspring.com/~meauxracing/

Support Israel - Genesis 12:3