gm

Since I bought my 911SC 10 years ago, I have searched for ways to improve the universally maligned poor airflow through the cabin of this model.

My fan and vent valving all work as intended (though the fresh air fan on pos. 3 equals take-off of a 727, but still rather little airflow, considering the noise.)

To increase airflow through the cabin, I have additionally removed the foam lined panels, accessible through the zippered headliner opening above the rear window, which improved the air volume that is exhausted, and circulation in the cab a bit.

Still- even on moderately warm summer days the air movement inside the car is too poor-unless I open the roof or side windows (too noisy at speed)

So- what can I do? Is there a way to harness more of the air scooped up by the hood cowl? Would bigger hoses help? If so which ones?

What about using the idle air-conditioning hoses/fan and outlets to bring additional fresh air into the cab? (I have removed AC from the car-the inefficiency, weight and power reduction of the stock AC on my model did not add up to the marginal cooling it provided)

I sometimes turn the AC fan on, but the air blowing into the cab is warm, as it is sucked from somewhere inside the trunk, and not from the great outdoors.

Any recommendations?

Best regards,
GM

KC911

Since you've already removed your A/C, maybe this thread will help...

http://forums.pelicanparts.com/showt...resh+air+a%2Fc

Keith

gm

Thanks, Keith.
The thread you posted refers to a nice mod to improve the BLOWED air (hooking up the three AC outlets to the fresh air blower)

I am still wondering how to get more (passive) air through the cab, for better venting in general.

I cannot believe that a big air intake scoop like the one over the trunk lid on 911s, and smack in the line of oncoming air cannot push more air through the cab!

GM

jet911

I agree. IMO this is one area where the P-car engineers did not put in a lot of time. One simple lever (as is with nearly any other car on the planet) to open a vent to let air directly in the cabin would have been too easy. Oh no, they had to put 3 fans (of which none work worth crap), to add weight and add additional things to go wrong and it didn't accomplish much of anything except a lot of noise. You would have thought with the crappy AC in the car, they would have at least put in a decent vent.

I don't drive my car on warm/hot days due to the horid lack of air circulation in the car. I never bother with re-charging the AC as it lasts for only about a month.

Peter Zimmermann

OK guys. Yes, the fresh air system is crappy, and yes, the A/C system is even worse. But in all fairness that '78 car is almost 30 YEARS OLD! And they were made, in large part, to be driven in Europe/Germany, where ambient temp rarely exceeds 80. It's 110 every day where I live, often for 4 months straight. I do with my SC what guys in Minnesota do in the winter - leave the car in the garage. Anyway, whomever figures out how to flow more air in our cars is going to become a rich man. I recently gave up on my A/C, I was faced with all new barrier hoses, a new compressor, rec/dryer and new evaporator housing fan. I said heck with that and put a new set of Bilsteins on the car instead. It's a shame because eventually the repair cost, even when you do your own work, can become ridiculous compared to the comfort available. My '82 is a beautiful car, but working A/C is never going to affect what it's worth. When my A/C was working well it would barely keep up with 92 degrees, let alone 100-110. I guess, if you live in a more temperate area, it might be worth the restoration cost.
Pete

jet911

Hi Pete,
My car is an '86 coupe. I guess my point is that I was quite suprised when I bought my car 5 years ago, and went to open the the fresh air vent and could not find one. I read the owners manual and followed the instructions for allowing fresh air to circulate in the cabin, but I could put a feather in front of the center vents where the air was suppose to come in and zero movement at 80 mph. Next, I stopped by the P-car dealer thinking I was doing something wrong and was informed there was no fresh air vent other than the fresh air fan which is loud and works only if you want fresh air on your feet or windshield. I could buy the Europe/Germany explaination of not being as hot, except that I have an 88 BMW, and it has a fresh air lever that allows as much fresh air in the car as I want, as do all the 5 series models back to 83. I have had other BMWs of earlier vintage (2002s) and they also had fresh air vents. A fresh air vent would have simply been a lever that allowed the air coming in from the vent above the truck to enter the same hoses that the AC uses when the lever was moved to the opened position. I just think that in such a highly engineered car, something so simple sould not have been overlooked. After all, they were producing cars to be sold around the world, not just in Germany/Europe.

I have grown to live with it and like you, on the hot days, simply leave the car in the garage.

Take care Pete.

Regards,
Jim

gm

Pete writes:
How hard could that be? Either now, for me to install retroactively, let alone since inception of the model, some fourty years ago?

I am amazed that the many fine owners of this superior automobile obviously never found the stale cabin air cause enough to tempt the engineers in Weissach or Zuffenhausen to come up with a simple solution, as their cousins over in Wolfsburg did, where a similarly front-air scooped automobile, the VW -Bus, had said air vents since the 1950s, to the point that your head almost blows off when they are wide open...

I am further amazed that in a country like ours where no less-than-perfect feature of a new model is left untouched by aftermarket entrepreneurs for more than a few months after introduction, no solution has been offered to this decades-old problem yet.

GM

Dan Cobb

I managed in increase the movement of air through the cadin by back-dating the rear quarter windows to the opening style.
It was not an easy project, and I would not recoomend it to anyone afraid of doing something that cannot be "un-done", as it is a permanent modification.
Although i probably have the only 84 Carrera with opening windows for miles around, the improvement was minimal for the effort required.
I was thinking of ducting the center vent directly to the front grill, but such an approach would not provide any control over being opened or closed.
It's hard to believe that there are so many options available to cool the brakes, but none to cool the driver.
+++

redidrum

Since my recent a/c mod., my a/c is great. Not as good as my 4 runner, but, much better. Larry Hadler at Auto Air and Heating Inc., in New Palestine, Indiana does great work. He blocks off the lower a/c vent which doubles the upper vent for much better movement. He is at (317) 440-6767. http://comefixit.com Changed all barrier Hose, Rotary Compressor, Receiver/ Dryer, and Condensor. I had my windows tinted and then we were set. Yesterday I hauled the kids in the back seat with a 95 degree day and we were all comfortable. I bought and returned the Kuehl vents after seeing that I'd need to drill holes in my under dash. Never Drill De Porsche !

Good Luck,

Ron

gm

Just to be clear- you write
I don't have a "lower a/c vent" on my SC. Do you mean he blocked off the tiny side a/c outlets, in the right and left corners of the dash, in favor of the center dash outlet?

GM

Peter Zimmermann

gm: Your lower vent looks like a black plastic bow tie on the vertical bulkhead just forward of the center console (under the dash). From my experience blocking it off is usually not done, enlarging it and installing a directional vent is far more common.
Pete

redidrum

gm,

I just spoke to Larry Hadler at Auto Air 317-861-4898. He can give you some tricks of the trade to get more airflow on 911 cars. He does a lot of them. As Pete said you can block off the bowtie vents. Larry blocks it with putty at the 1 1/4" vent going to the bowtie between the controls.

Good Luck,

Ron

Ron

eyeflyalot

Roll your windows down more!

Bill Gregory

There is an easy racing mod (kits are sold for this) which replaces your clock with a hose hooked up to the outside vent.

jet911

Bill,

I've searched a few sites (Pelican and another couple internet sites) and cannot find the kit you mention. Any ideas who sells them?

TIA

Jim

'86 Carrera Coupe