Cooling System

Admin, that radiator looks great. Would love to see fitment pictures, interested in knowing if it requires any modification to the original radiator support. Also would be interested to know how much clearance between the front end drive parts and the fans.

I'll post some pictures on Monday. there should be plenty of room between the fans and the water pump pulley. also it cleans up all the hose cross over connections. You shouldn't need to mod the factory support either. I deigned this to be a blot in , no cut, cooling solution for our conversions.

That's a nice piece of aluminum! Any reason for not using the stock fans from a 951?

The way the radiator is designed I did not think the stock fans would work, also the radiator is taller than a stock radiator, which means the stock fans would need fab work needed to fit.

What CFM are the fans? How is the shroud mounted? Will the shroud and fans be available seperately?

Admin wrote:also the radiator is taller than a stock radiator

Does this mean your rad will hang lower than the stock rad?

Admin wrote:with a shroud , you are not blocking the radiator. If the shroud is designed correctly, like the one on my new radiator, it forces the air to pull through the complete radiator surface and not just in the area where the fan is mounted. If you have an unshrouded radiator you can loose all the cooling area that the fan does not cover.

Eric, looking good.
I had made a shroud just like this one about 5 years ago, with 2 SPAL fans.
There were 2 things i took away from that experiment. First, my flat faced shroud with depth similar to yours really restricted the flow of air at speed and for me that led to increased coolant temps when compared to running without the shroud and fans at all. I would guess that the reduction in open area and the turbulence caused by the flat "wall" the air encountered at the top and bottom caused this reduction in cooling efficiency. Most OEM shrouds either have a smooth curved feature that meets with the fan or one-way flaps to increase open area at speed. So I then added some homemade one-way flaps across the top and bottom of the shroud....much like the ones pictured below. Though using a piece of reinforced rubber sheet or the like is not very hi-tech it does the job and allows you to make odd shapes. The addition of these one-way flaps helped the flow at speed by opening and increasing the area. These same flaps allowed the fans to do their job properly as you described above, by closing shut.
My 85 Scirocco has this style of one-way flap on the factory shroud; my Mk5 TDI has a more elegant molded plastic version.
The second thing learned was that even the SPAL fans I had, which had some of the highest CFM's in the industry, were not quite up to the task in summer with the AC on. BTW the factory 6 blade fans, which have a deeper blade, were able to pull a little more CFM though my "CFM test rig". I bought at least 3 different fans to test CFM, not all of them lived up to their marketing so be sure to try and do a comparative test before settling on a model.

I too will be interested in the final cost of this set-up. Thanks, as always, for tackling these types of projects. 

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