Engine decluttering

[rwest]

Originally Posted by DaveMcKenz

I have no doubt you are right. How does it work?
Thanks,
Dave

Air always run through the exchangers to heater boxes and the cable from the cabin moves a set of vanes that either sends the hot air up to the cabin or sends it out into the airstream under the car.

[DaveMcKenz]

That sounds right. I remember the valve to the cabin, but forgot the valve that opens beneath the engine.
Thanks.
Dave

[emcon5]

Originally Posted by rwest

Air always run through the exchangers to heater boxes and the cable from the cabin moves a set of vanes that either sends the hot air up to the cabin or sends it out into the airstream under the car.

This.

Take a look at the tech article on flapper boxes, it show where they are.

https://www.pelicanparts.com/techarticles/tom_sharpes/heater_box1.htm

One thing to be aware of, without the blower, the airflow through the heater is dependent on the speed of the engine fan, and therefore engine RPM. If you are sitting at a red light at idle, there isn't much heat.

[Jack Stands]

That’s why we have a gas pedal and lower gears while driving! I never had any complaints with the early style heat exchangers in my 911s or 914-6s. Perhaps defrosting is a bit slower, but once you understand how the system functions, it’s completely logical.

[RDM]

The flapper valve closes off air going into the car, and at the same time opens below the car so that the hot air from the exhaust manifold is vented there.

[Jonny H]

Originally Posted by DaveMcKenz

I have no doubt you are right. How does it work?
Thanks,
Dave

Essentially, when the valves are closed to the cabin, they are open to the ground and vice verse. So you always get air flow over the exhaust.

Edit. Oops, already answered several times above!

[emcon5]

Originally Posted by Jack Stands

That’s why we have a gas pedal and lower gears while driving!

Moving isn't a problem, that is why you open the sunroof. Airflow makes it a low pressure area and pulls the heated air in through the heater pipes.

Sitting still for any length of time, you really need to increase the engine RPM to get any significant airflow through the heater.

Never really bothered me, but it doesn't change the fact it happens.

[universeman]

I have a targa not a sunroof car, but are you sure you even need to open the sunroof to get air pressure differential? The vents above the rear window (or on the roll bar in a targa) do that by design.

[McLaren-TAG]

This should motivate you.

[RocketWrench]

Originally Posted by 911SC SKI

Type911.co.uk can provide the parts needed for the heater back date. Ditch the blower.

Found 'em! Thanks...

[fred cook]

Originally Posted by RocketWrench

Here is my engine as it is right now:

"Scoundrel", not Outlaw...



Its out and I am rebuilding it and the car is in the paint shop having the engine bay resprayed in the outside colour.

As you can see, its quite cluttered in there, so am looking for real-world advice on how to de-clutter the engine without harming performance.

I have seen people cutting down their airboxes, drilling holes in or replacing them with cone filters. How much of a bad/good idea is this?

Secondly, there is too much pipework criss-crossing the engine: How do I get rid of that, or re-route it in a way that I don't have miles of piping everywhere?

Finally, how do I tidy the wiring up so that it looks more ordered?

I have my own ideas, but having worked in isolation on this car for years now, not all of my ideas are good.

Here is a picture of my SC engine compartment after an engine rebuild from 3.0 liter to 3.3SS, heater blower backdate, CIS backdated to 1973 1/2 status and the addition of Electromotive XDi crank fire ignition. Notice all the space where the distributor used to live! The coils are mounted on a shelf between the firewall and the engine. The CSI backdate got rid of lots of bits and pipes! The engine is running in this picture.

[drcoastline]

Originally Posted by al lkosmal

send your engine to me....i'll provide some serious de-clutterage.




regards,
al

OH MY GAWD that is a thing of beauty.