View Single Post
Old 05-12-2011, 09:14 PM   #12 (permalink)
cleanspeed1
Diesel Addict/No Cure
 
cleanspeed1's Avatar
 
Join Date: Apr 2011
Location: chicago, il
Posts: 787

StolenHoopty - '90 Honda Accord EX

HvyDrnkr - '93 Cadillac Seville
Thanks: 130
Thanked 74 Times in 49 Posts
Quote:
Originally Posted by redpoint5 View Post
Why don't manufacturers turbo-charge all cars? It seems a sure bet it would more than pay for itself by avoiding the need to build a bigger engine, and in fuel savings.



My point is, it would actually be desirable for fuel to instantly combust if it is directly injected into the cylinder just at the right moment in the engine cycle. It shouldn't then matter what octane the fuel is since we want it to burn right as it gets squirted in. Diesels do this.

Surely gasoline engines can be designed to withstand the increased pressures, heat and such. Diesel engines do this while burning a fuel that has 30% more energy density.
It gets back to the chemistry of the fuel. Even though gasoline direct injection and diesel direct injection do the same thing, the fuel reacts differently.

Look at what happens between seasons with the blends of gasoline and diesel. Mileage usually drops. Gasoline with ethanol versus alcohol free gasoline, there is a mileage difference. It's like that because the fuels are designed to burn instead of instantly combust like you mentioned, and because of this, no engine running on what is accessible at the pump will run as good as it could.

The engineers and chemists can do a lot more in terms of efficiency, but are only going to be allowed to go so far with it because of business. It's unfortunate, but that's the reality.
__________________
Volvo WIA42 VED-12 / 335 hp / 1300 ft/lbs / 9 mpg

Big n' Boxy, Never met a Hill it Didn't Like
  Reply With Quote