12 blade 964 fan question

[1303C2/3]

How much clearance does it have with the engine lid closed. I wonder if the shroud assembly cold be moved a little further back from the engine in order to get more air over the nr. 2 cylinder.

[Arnoud]

I know that there's a small and a large diameter kit available from the guys that supply CSP:http://kaefer.motor-sport-service.de...asehauben.html

They're 260mm diam.-I don't know how big the outer diam.of a 964 12-blade is.

Regards,Arnoud

[itHaKa]

finally we ended up machininig the fan so it can fit an earlier 911 housing
so we had to machine the alternator mounting , since the fan is wider , and decrease the fan´s diameter , also the hub had to be modified so it will accept the old key.
the good thing is that we can switch between fans on the same housing since all of them will fit

in the future we will dyno the 5 blade vs the 11 blade vs the 12 blade fans !! and we will post the results

[effvee]

[/QUOTE]

Hello, nice how you have over come the 12 issue. From what I have read, the 11 blade and it outter ring is bias to the 1&2 cylinder. Since you ommited the otter ring, you might have an even greater over shock of 1&2 cooling. I believe Wally did some work on the 11 blade and 12 blade. I don't know the in's and out's but try and ask him.

Lastly, I see your pullies, you may be loosing allot of why you are using the 12 blade setup, using the larger OD Alt pulley. Will the car be in cold climate? That fan needs to turn, even more at idle after coming to a stop in traffic and you engine has been working hard.

Just my 2 cents.