Tube count; when less is more. Fin Surface Area;when more is a whole lot more.

Question: Is tube count important ...

When selecting a Model A replacement radiator? I am interesting in purchasing an Extreme Touring 11FPI 1930 non-pressurized unit. What is the tube count of this unit?

Answer: It is important but its part of the larger "equation"

  • The geometry of the tube is important - We use a 3/4" elliptical or "flat" tube. The Rouge plant used a 3/8" "Jelly bean"
  • The tube wall thickness is important - We use a 007. wall.  Ford used a .015. Which explains part of the added weight
  • The tube construction is important - We are laser welded. Ford was a lap seamed solder joint that is an older construction technique and prone to failure.
  • The aggregate area of the opening of the tube is important. We are 2.6% greater
  • The aggregate volume in the tubes is important. We have 10.3% more volume in aggregate.

So in short, there are fewer tubes but because of their shape and construction they have more surface area in contact with coolant and, concomitantly, more in contact with fin.

This is part of the the reason they cool better. The other part is the fin.

Question: What's the difference between Active Driving, Extreme Touring and Show?

An increase the cooling fin density reduces engine temperature.  Why?  Because aggregate fin surface area is really nothing more and an  "opportunity for heat exchange" between the source e.g.coolant and the sink e.g. the air.  We pulled the data from the Ford plants and compared it to the radiators we make today for active drivers, extreme touring and those who show to illustrate the scale of the cooling area increase and cooling improvement.