Itinerant Air-Cooled

No I dont think they are needed if you are running lower tins.

This engine is going in my 72 bus just to make it mobile.

those are type 3 cooling parts. different fan, different fan housing, different airflow design. use type 1 tins with type 1 fan shroud, use type 3 tins with type 3 fan shroud.

vdubyah73 wrote:those are type 3 cooling parts. different fan, different fan housing, different airflow design. use type 1 tins with type 1 fan shroud, use type 3 tins with type 3 fan shroud.

Ah. Thanks.

neal

The "cool tins" are a type III part?? They are being sold as super cool tins for baja/rail (open end).

they are used by people that eliminate the sled tins. why would anyone want to leave their push rod tubes exposed, let alone second guess the engineers that figured out how to keep these things from melting?

My BAJA did not come FROM THE FACTORY like this... but it came to ME like this. I'm not running heater boxes (by choice) and my pushrod tubes ARE protected (by my skidplate) My baja has become my DD (75 miles each way) and has never indicated its running hot unless im pushing it.

bajaman72 wrote:The "cool tins" are a type III part?? They are being sold as super cool tins for baja/rail (open end).

The Type III deflectors are a decent improvement for upright cooling. They utilize the increasing knowledge of the VW engineers. The Type 4 deflectors are a further evolution of the same concept: by blocking the center area between the barrels and on up to the heads' intake ports, you get far more even temps across the cylinder heads and barrels. They allow more air to go around the outside surfaces of the barrels and to cool more exhaust port area and allow more heat to build in the intake area. These deflectors do not necessarily drop temperatures so much as help even out the dramatic temperature differential between the intake and exhaust sides, this could only help prevent cracks and dropped intake seats.

Jake Raby mentioned in 2005 that Type 3 tins drew more horsepower , and incorrectly concluded that the "restriction" caused it. But in actuality, any resistance in airflow would cause a drop in horsepower draw due to the fact that a fan's work is to move air, if you prevent it from moving air, it does not work as hard (see: vacuum cleaner motor speeds up when you stop airflow at hose).
Colin

how come vw didn't use these type 3 pieces in type 1 applications? they continued making type 1 for years after the end of type 3 production.

Thanks for the hows and whys Colin. Helps to understand it more than doing it because I'm told to.

vdubyah73 wrote:how come vw didn't use these type 3 pieces in type 1 applications? they continued making type 1 for years after the end of type 3 production.

Well, ask my engine what kind of an "expert" I am on the why and wherefores of VW's decision-making ... I can't get my 1600 stock bus heads to run anywhere near cool at 65.

The Type 3 deflectors were absolutely necessary for an engine with a crankshaft driven fan at one end of the engine. You had to seriously dam up the air to get a consistent air pressure through the entire head/cylinder runs. Same with the Type 4 engine.

The Type 1 engine has the fan right up over the middle where simple cylinder deflectors did the job just fine. Now why would VW add complexity where it was not necessary?

As for Type 3 deflectors on a Type 1 engine, I have no personal experience with whether or not they work at reducing overall engine temps. I personally think that they would not help overall cooling, but they would help a great deal with keeping the head temps more evenly distributed.
Colin