Jake Raby: Cooling system testing, reichert tuning? Options

[Aaron Cox]

title says it all, have you tried the horizontal fan system from reichert? at the autocross, saw a guy running this setup on a 2.7L type IV monster...

looked cool...but does it cool?

[Jake Raby]

You'll never understand it that way! I thought about it the same way till the engine and system taught me differently!

Until you have enough pressure in the upper plenums of the shroud it is impossible to direct the air. Thats why on my Type I DTM I ended up making the inside volume of the shroud 800ccs smaller and only then did I go from 5PSI to 9 PSI of plenum pressure. This pressure overcame to resistance of the vanes and then coupled with airfoil shaped vanes the problems were solved.

Reducing the plenum sizes and changing their shapes will boost the pressure made by the fan and help force the air out of the cylinders because its a radial fan with low volume and hi velocity..

The 911 system is different because it uses an AXIAL FAN which has alot of volume and less pressure. The holes being drilled in the shroud created a lower pressure area over the cylinders nearest the holes and the air did its best to take the path of least resistance and found its way to those parts of the shroud and cylinders. This is also impacted by the design of the under cylinder tins which we found on a TIV to create issues when using upright cooling.

The 911 system not having any vanes or deflectors benefitted from these holes being drilled, because without them all the air blows straight back on #3 and #1 and nothing to the cylinders below and underneath the fan- #2 and #4... The 911 engine does not have this issue because the fan is far enough away from the cylinders that the air does not have to bend 90 degrees to find its way there to do its job...

Without air pressure there is no way the air can be directed. A very perfectly created airfoil may overcome some of it but you still need pressure.

Lets just sum it all up by saying that I'm going to make the cylinder tins work better! Plus they will look cool! Plus they will be LIGHT!