I heard recently that some donks aim the exhaust at the rear wheels so that when you do a burnout the smoke from the tires billows out and looks cooler. This makes sense and I think donks are hilarious so I approve of every single step in this process.
Then I got to thinking about the temperature of that exhaust at the rear of the car. Seems like it doesn't get much above 300 degrees in most cars. Then I got to thinking about the temperatures where brakes start fading, which seems to be 700-800 ish with a streetable performance pad. Then I got to thinking that perhaps a steady stream of 300 degree gasses on those rear rotors might be a really good way to get the pads up to operating temperature when they're cold and to cool them off when they're really hot.
Is this as stupid as I assume?
Im not sure... I just know I’ve never had a problem with rear brakes getting too hot.
Mr_Asa
SuperDork
11/19/20 11:11 a.m.
You'd likely have to have the exhaust exit right on the calipers for any effect, and then the air moving around from vehicle movement and wheels turning would likely negate any effect.
There's a lot of water vapor in exhaust. May not want to hose your brakes down with condensation.
The condensation would cool your brakes.
Its not a terrible idea in a Smokey Yunick sort of way.
You think too much - - clearly not Donk material....
Image is everything. If it looks cool, what more do you need to know?
Use the exhaust to spin a turbo, but all the compressor does is blow air on the brakes?
Point it out directly in front of them, back at a 45* angle. It's fun watching the tire smoke blow back on videos, not something i can see while i'm heating my tires though
Some burnout pros have the brake bias set so that in effect the rear brakes don't work at all.
In reply to ¯\_(ツ)_/¯ :
I am doing this!!
Who has a junk turbo that I can borrow? And two large intercoolers.
I don't understand why NOBODY has ever thought to have a valve that directs warm exhaust INTO the car during the winter to use as a heater. Can someone figure out what I am missing? Seems to be a smart reuse of spent energy and as a bonus will improve emissions drastically since no carbon pollution will be entering the environment outside of the car.
Was going to start another thread but thought it better to piggy back on this one to keep all of the best ideas in a singular place.
Mr_Asa
SuperDork
11/19/20 3:41 p.m.
Olemiss540 said:
I don't understand why NOBODY has ever thought to have a valve that directs warm exhaust INTO the car during the winter to use as a heater. Can someone figure out what I am missing? Seems to be a smart reuse of spent energy and as a bonus will improve emissions drastically since no carbon pollution will be entering the environment outside of the car.
Was going to start another thread but thought it better to piggy back on this one to keep all of the best ideas in a singular place.
Cause people like not dying?
But VWs had that in the 60s and 70s. Exhaust routed through double walled pipes and the blower for the hot air pushed air from those into the cabin. Gotta do something to heat the passengers when you don't have hot coolant
Mr_Asa said:
Cause people like not dying?
Not to be argumentative, but I've never, not once, heard a person who died say he didn't enjoy the experience.
1988RedT2 said:
Mr_Asa said:
Cause people like not dying?
Not to be argumentative, but I've never, not once, heard a person who died say he didn't enjoy the experience.
And who the hell doesnt like helping he environment while they are at it!
DaewooOfDeath said:
I heard recently that some donks aim the exhaust at the rear wheels so that when you do a burnout the smoke from the tires billows out and looks cooler. This makes sense and I think donks are hilarious so I approve of every single step in this process.
Then I got to thinking about the temperature of that exhaust at the rear of the car. Seems like it doesn't get much above 300 degrees in most cars. Then I got to thinking about the temperatures where brakes start fading, which seems to be 700-800 ish with a streetable performance pad. Then I got to thinking that perhaps a steady stream of 300 degree gasses on those rear rotors might be a really good way to get the pads up to operating temperature when they're cold and to cool them off when they're really hot.
Is this as stupid as I assume?
Did you get the idea from the latest donk episode from Hoonigan?
Mr_Asa said:
Olemiss540 said:
I don't understand why NOBODY has ever thought to have a valve that directs warm exhaust INTO the car during the winter to use as a heater. Can someone figure out what I am missing? Seems to be a smart reuse of spent energy and as a bonus will improve emissions drastically since no carbon pollution will be entering the environment outside of the car.
Was going to start another thread but thought it better to piggy back on this one to keep all of the best ideas in a singular place.
Cause people like not dying?
But VWs had that in the 60s and 70s. Exhaust routed through double walled pipes and the blower for the hot air pushed air from those into the cabin. Gotta do something to heat the passengers when you don't have hot coolant
No. That's not why! It's because they need that exhaust to route into the intake to supercharge the intake!
Exhaust heat exchangers are also used on air cooled small airplanes. Anyone who has been in both will recognize the unique "hot metal" and slightly "oily" smell those heaters have.
There was at least one large post war radial engine that used an Exhaust Power Recovery Turbine that linked an exhaust driven turbine directly to the crank. Seems weird, but it must have created some power over whatever the exhaust restriction cost.
Cooter
UberDork
11/20/20 3:42 a.m.
Since this is where this thread is ultimately heading, I figured I would save us some time.
aircooled said:
There was at least one large post war radial engine that used an Exhaust Power Recovery Turbine that linked an exhaust driven turbine directly to the crank. Seems weird, but it must have created some power over whatever the exhaust restriction cost.
Turbocompound engine. In some cases they were recovering almost as much energy as the piston part of the engine was making, so they realized, hey, why not just get rid of the piston engine part and save on maintenance?
In reply to Brotus7 :
Yes, yes I did. I love that series for its wonderful, joyous pointlessness.
Though I don't think they were going to use it for brake cooling. :)
Mr_Asa said:
Olemiss540 said:
I don't understand why NOBODY has ever thought to have a valve that directs warm exhaust INTO the car during the winter to use as a heater. Can someone figure out what I am missing? Seems to be a smart reuse of spent energy and as a bonus will improve emissions drastically since no carbon pollution will be entering the environment outside of the car.
Was going to start another thread but thought it better to piggy back on this one to keep all of the best ideas in a singular place.
Cause people like not dying?
But VWs had that in the 60s and 70s. Exhaust routed through double walled pipes and the blower for the hot air pushed air from those into the cabin. Gotta do something to heat the passengers when you don't have hot coolant
But it seemed that to make it work I had to drive the bug in second gear to get any heat.... :)
