why is the 993 worth so much more than a 996?
03-18-2008, 10:39 PM
#301
Banned
This is the only reason to me to move to water.
Yes and no, for the first statement, it depends on many more variables. Cylinder wall thickness, cam specs (duration and overlap), cylinder head config., compression ratio, etc....
You say it is not an issue with water, you will have to increase volume and surface area of the radiator to adjust to heat dissipation, same with air.
Came out around the same time actually....
Yes and no, for the first statement, it depends on many more variables. Cylinder wall thickness, cam specs (duration and overlap), cylinder head config., compression ratio, etc....
You say it is not an issue with water, you will have to increase volume and surface area of the radiator to adjust to heat dissipation, same with air.
Came out around the same time actually....
03-19-2008, 12:25 AM
#303
Nordschleife Master
03-19-2008, 01:00 AM
#304
isn't it true that Porsche went to water cooled because of noise suppression and emissions issues and NOT heat dissipation????? And isn't it also true that even while making air cooled roadcars their race cars had already gone water cooled???
03-19-2008, 01:53 AM
#305
Ironman 140.6
Rennlist Member
Rennlist Member
It was both. One specific reason was they said they could not make a 4 valve head stay cool enough on an air-cooled car. They felt they needed 4 valves per cylinder to get better power output.
03-19-2008, 02:17 AM
#306
Ironman 140.6
Rennlist Member
Rennlist Member
He writes the following;
"There were many reasons for abandoning the air-cooled motors..........
But the most important was that experiments made with air-cooled engines having four valves per cylinder had indicated that adequate cooling of the cylinder heads and valve seats was impossible to achieve. Four valve technology, however, was essential to achieving a high specific power output, while at the same time meeting current and future emission regulations worldwide. Liquid cooling also does away with the large cooling fan, a major source of noise; it also has the advantage of better noise absorption and considerably simplifies the cockpit heating system."
So that is probably the real reason................OR ...............BruceP is right and "It's a conspiracy, perpetrated by the evil coolant industry bent on world domination. The air-cooled engine has been killed, just like the 100 mpg carburetor, by corporate malfeasance."
03-19-2008, 03:36 AM
#307
03-19-2008, 12:30 PM
#308
I knew I read this somewhere. I just dug out my "Porsche 911 Story" by Paul Frere.
He writes the following;
"There were many reasons for abandoning the air-cooled motors..........
But the most important was that experiments made with air-cooled engines having four valves per cylinder had indicated that adequate cooling of the cylinder heads and valve seats was impossible to achieve. Four valve technology, however, was essential to achieving a high specific power output, while at the same time meeting current and future emission regulations worldwide. Liquid cooling also does away with the large cooling fan, a major source of noise; it also has the advantage of better noise absorption and considerably simplifies the cockpit heating system."
So that is probably the real reason................OR ...............BruceP is right and "It's a conspiracy, perpetrated by the evil coolant industry bent on world domination. The air-cooled engine has been killed, just like the 100 mpg carburetor, by corporate malfeasance."
He writes the following;
"There were many reasons for abandoning the air-cooled motors..........
But the most important was that experiments made with air-cooled engines having four valves per cylinder had indicated that adequate cooling of the cylinder heads and valve seats was impossible to achieve. Four valve technology, however, was essential to achieving a high specific power output, while at the same time meeting current and future emission regulations worldwide. Liquid cooling also does away with the large cooling fan, a major source of noise; it also has the advantage of better noise absorption and considerably simplifies the cockpit heating system."
So that is probably the real reason................OR ...............BruceP is right and "It's a conspiracy, perpetrated by the evil coolant industry bent on world domination. The air-cooled engine has been killed, just like the 100 mpg carburetor, by corporate malfeasance."
I like the second theory by BruceP better. Makes much more sense. It gives alot of credit to the air-cooled guys.
03-19-2008, 12:39 PM
#309
I just looked up ethylene glycol on Wikipedia. Apparently, it was first prepared by a French chemist. So I guess we have to invade France to stop this madness.
03-19-2008, 01:20 PM
#310
Ironman 140.6
Rennlist Member
Rennlist Member
At least it's a short trip from Iraq. It should also be an easier occupation...
Fire up the tanks.....we're rolling out for coolant.....
03-19-2008, 06:40 PM
#315
Race Car
Brucie, ls, Benny, not arguing, I call it stimulating conversation, me and my friends always talk this way. Just stating air/oil cooling could of continued on if Porsche wanted to. The only thing that would of been hard to manage is the noise, but alternating fan blade spacing creates less noise than equal spaced blades. Old tech that worked, look at your SUVs cooling fan........ bye guys, dont want you think I am arguing about this, I am happy I dont have to worry about my water pump failing now for the time being. 
bye guys, dont want you think I am arguing about this, I am happy I dont have to worry about my water pump failing now for the time being.