muso1958

Hi no good if you dont live somewhere hilly perhaps ,but here goes .
I had this thought that if i put a switch in the inlet manifold that closes when in overrun .it could be connected to the air con system & give you some form of air con for free ,also saving on brakes & improving engine breaking .
need to find suitable switch .
any ideas? thoughts on this
please let me know .

kennycoulter

im a little confused. maybe explain it better? im also 3/4 retarded, so im sure its not your explanation. or draw a pic in paint, and post it here and edit the title to say *with pics!!!11!!!* that wil get lots of attention.

jmporsche944

Ive... Never... Been... So... Confused... In... My... Whole.... Life...

art

I used to do this in the old days before automatic climate control, switch on the AC on downhills and off on uphills-worked well on a late '70s accord.

Tom M'Guinn

I presume N/A cars have a TPS (like the turbo) so you'd already have the sensor telling you when the throttle is closed. You could also tap into the Tach signal to sense when you are over a set rpm. Then build a little AND gate that engages the A/C when the throttle is closed while the motor is above idle and you're there. Wonder how long the A/C clutch would last?

muso1958

thought of the comp clutch .but listening to mine when dash fan isnt on max .it cuts in and out every 30 seconds anyway . would'nt have thought it would affect it being electro magnetic .

White Pony

I wanna take my AC compressor out completely.

It's a big piece of doo doo.

Zero10

This idea is exactly the same as pushing the button every time you go downhill.
The principle is fine, but the implementation is where it suffers. It makes more sense to just turn your A/C on, and enjoy it all the time. If you're really looking to get free A/C, then only push the switch when you're going downhill.

muso1958

dont agree . there are a lot of obvious advantages in this.
and if you live in a very hilly area as i do & i'm sure others do ,it would'nt be long before you wore your switch or finger out
i realise this isnt for everyone ,but it could save a lot in brakes over heating engines etc ,for others .
the only weak point in the principle i can see is the comp clutch ,but if you've ever turned down your stereo & listened to how often it cuts in and out under normal operation ,you would see this isnt an issue .
I only really thought of this as i discovered my 944na ,was really flat when air con was on .so i used to leave it off in favour of the extra HP .
i will let you all know how i get on

Eyal 951

http://zeitronix.com/tcac/tcac.htm

$ 55

...and I can sell you them.

inactiveuser92616

interesting idea; seems like it would work decently so long as you gave it some logic or carefully programmed hysteresis so it wouldn't eat up the AC clutch.

FRporscheman

My 1995 968 has a feature where if the AC is on, and you try to accelerate or are just trying to pull uphill, the AC will shut off until you let off the throttle. I think it's FRIGGIN awesome, because now I can just leave it on all the time, and it will shut the hell off on it's own when I try to step on it.