[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]
I did place the sensor on the same spot as the MOFOCO head. The MOFOCO head had almost no outflow cooling through the exhaust valve area , no air going through there. It did have extra fins that were very thick, lots of extra metal all around. I do understand about thick and thin metals heating differnces but on thick metals, it is slower to heat up and then there is a saturation point that needs to be cooled off in order for the temps not to increase , needs air over the surfaces or the heat will just sit and increase. The Mexican head seams to take advantage of the cooling characteristics of air. I understand that some metals conduct inside heat better to the outside . Cooler outside will pull more heat from the inside. The sensor is hooked up to the a hotspot that is now a better cooled section (exhaust valves). On the VW experimental aircraft site, all the folks there are concerned with cooling around the exhaust valve areas to save valves from a short life , that is typical with all aircooled, this Mexican head seems to address the problem. The head seems to work as well as the MOFOCO big valve since I did not notice the difference with these small valves. I did notice that the head was made without much casting protrusions around the valve stem area below the valve head, giving it more flow. This was usually a trick with flowing a head by grinding these off, including the valve stem. On the Mexican head , the valve stem only sticks out without the casting protrusions. My temps today without, pulling back on the abuse, never got to 350 degrees on the Mexican head, the MOFOCO head on the better cooled side got a little higher than 350 degrees. In idle the mexican head is 'stone cold' around 225 degrees. I will let you know what happens, fingers crossed. LEON MARTINEZ ------------------------------------------------ To unsubscribe, E-mail to: <type3-off@vwtype3.org> For more help, see http://vwtype3.org/list/