[Outlaw 911]

Hi Todd-

Great 911 LS1 build - fun to watch from the side lines.

Please remember the following is must my observations and opinion - but I did stay at a Holiday Inn last night. Couple of things to consider for the cooling issues:

1 Radiators are not designed to be layed flat - like in your current configuration - any air in your system is either sitting in the side tanks or the tube/finned area- any air in the tanks or tube/finned area will lower effeciency considerably.

Suggestion - tilt the radiator with inlet higher than the exit - like it was designed to do. Wont take much of tilt, but get the air to the top.

2 Once a 911 is rolling down the highway the area above the engine grill or whale tail is a low pressure area - meaning that air will be drawn up from the bottom of the engine compartment through the radiator. Think air plane wing - the rear of a 911, even with a tail is sloped like a wing and the trailing area - the roof, back glass and engine lid are in low pressure zone. In a 911 with the air cooled engine -the engine cooling fan pulls a ton of air through the grill and this is not an isssue. Look at mid 80's 935's , they raised the back of the 911 body way up in the air and ducted air to the engine fan from the side of the body to help elminate this low pressure area.

Hence the reason when sitting still, your fans can push air through the radiator, but once moving they are fighting the native aero of the 911. I would guess there is very limited air moving through your radiator at speed - hence the reason you run warm on the high way, but cool at idle.

Suggestion - 1) install 2 large Subaru WRX STI style scopes on the top of your grilled area of your tail to grab air coming off the back window (this will give the air in inlet via high pressure) and 2) then vent the tail/lid with very large holes/vents above the rear center reflector below the trailing edge of your tail - - so you have an exit (even more important than the entry) in a low pressure area - sucking the air through the radiator.

3 If the raditor is the highest point in the cooling system - that is not good - get an expansion tank - not a surge tank - and place it a few inches higher than the high point in your cooling system....get the air to to the tank and out of the radiator.

Hope this helps.

Outlaw 911