T4 Engine tin: thermal design Options

[914werke]

So seeing a product recently got me thinking about the result of its application & my own observations of how well (or not) the T4 handles air flow, Engine block cooling & resulting oil temperatures. (IMG:style_emoticons/default/smile.gif)

Its somewhat well known that ...in the 914.. the T4 suffers from less than optimal cooling from the front mounted impeller/fan particularly to the #3 Cylinder
& that it is vitally important to seal the tins multiple openings to contain as much laminar air flow front to back over the finned cylinders.
In a gross approach, the goal was to seal the engine compartment "intake" air on top from the eng. heated "cooling" air below the tins.
When a motor is new and all its components serviced & refreshed, the design does, or did, a pretty good job.
After years of use (neglect), elements (oil dirt mice ext) conspire to restrict that air flow.
As well as eng. heat causing hardening of rubber pieces that are intended to help contain that cooling air below.
Now almost 50 yrs on I see fewer & fewer "STOCK" engine configurations which you can guess usually means more heat to deal with.
Jake addressed the cooling air via his(?) DTM solution, but IMO its not very practical for stock or near stock motors (& expensive)

The go-to response to eliminate that heat is usually an additional or a remote oil cooler which comes with its own set of challenges. (IMG:style_emoticons/default/confused24.gif)
How about KISS (IMG:style_emoticons/default/biggrin.gif) Has anyone used any of the Fiberglass based stick-on reflective heat shielding products on the engine-sides of the tin?
Idea being rather than allow heat absorption to all the those steel pieces reflect it back to carried away by the cooling air?

BTW Im not a Porsche engineer...but I did stay in a Holiday Inn last night (IMG:style_emoticons/default/happy11.gif)

[ClayPerrine]

If you want to improve the engine cooling, you need to realize that the designers of the 914 didn't realize that the air intake for the engine compartment is in a low pressure area. The air moving over the top onto the rear decklid creates a suction at the engine compartment.

So the engine runs hotter than designed. But there is something that can be done for it. Upgrade the Floor Pan Air Deflectors.

(IMG:http://www.914world.com/bbs2/uploads_offsite/www.mecatechnic.com-1143-1680185732.1.jpg)

These were added to improve the engine cooling by creating a low pressure area under the car to pull out the hot air. They were a step in the right direction, but they can be improved.

Go to your local big box home improvement store and buy some rubber garden edging that is taller than the factory air deflectors. About twice the height works. Then attach it to the front edge of the engine compartment, running the whole width of the car.

It's rubber, so it won't hurt it if it drags a little on speedbumps, and if it is too low, just shorten it up a little. The extra width and length will cause a low pressure area under the car when moving, and that will draw air through the engine.

It helps to have all of the holes blocked and all the engine compartment seals intact and functioning. An external oil cooler will also help.

Living in Texas, anything we can do to lower engine temps is a good thing. And this is a cheap and easy thing to do.


Hope that helps.