Hi all,
I read thru the whole thread... almost 1500 posts. Extensive and impressive work you all have done.
A few questions and observations:
Does anyone know how the aircraft guys with EG33s have solved this? They must be able to run at full song for quite a bit and very reliably.
http://www.canardaviation.com/Philli...g%20System.htm
http://www.youtube.com/watch?v=1nK8bc-GUyc
This guy lives close to Houston, but I have not been able to find an e-mail address.....
Under normal commuting my EG33 runs between 1500-2500 rpm, rarely goes up to 3000. I trust a WRX or any other four cylinder runs maybe between 2000-4000 rpm - yes? The six banger will produce more heat at a given engine speed, but probably app the same under same road / driving conditions, right? So maybe the cooling flow at a given engine speed had to be designed higher to cope high ambient commuting - and also high load low rev uphills with the TCC locked in.
If the water pumps look very close and the pulley is about the same diameter has anyone measured the crank pulleys? Maybe the EG33 is bigger? Naturally the cam pulleys must be bigger too
With the thermostate in the radiator outlet (at the pump) could the engine reach local boiling (at higher vehicle speeds) because the water flow the thermostate sees is too cool and it stays almost closed? Maybe the radiator has excess capacity under these conditions? Maybe Subaru had to design both the flow and the radiator capacity "too high" to deal with typical user conditions in high ambient slow operation under very low engine speeds (heat soaked). Also the air flow thru the radiator and under hood conditions maybe very different to Imprezas, as Bazza and Boxersix have implied.
I know moving the thermostate above the engine tries to fix this, but maybe it sould be at the engine and not too far in the upper hose. Also, the increased pump inlet may shift the flow rate related issues to higher rpms.... having said that, maybe reducing the pump capacity should be tested. What do you think?
Just tossing around thoughts aloud. My car spits coolant sometimes even under spirited driving on an ice track - if I use manual second. All is well if I use manual third - this keeps the revs down, but the engine is loaded much higher under boost to get the same performance.
Tapani