Is this possible II

Message

cannondale27 · #1 Post by **cannondale27** » Sun Sep 09, 2007 8:56 pm

Believe it or not the very first Fuel injection was actually direct injection.Mercedes was first way back.From what I understand by injecting right into the cylinder you are able to run much higher compression ratios since the gas cools.It is possible if using the E85 gas 15:1 plus a Turbo is possible.

Looking at these injectors made for DI it sure looks like it would be possible to do this.I know they require higher pressure but it is not like a diesel.
http://delphi.com/manufacturers/auto/power...sys/homogenous/
[attachment=4568:gas_multecdig_hom.gif]

SlOoT · #2 Post by **SlOoT** » Mon Sep 10, 2007 3:00 pm

And it is possible to remove the injector holes in the intake and polish the intake.

What would be the best position for the injector ?

J. Delaney · #3 Post by **J. Delaney** » Mon Sep 10, 2007 4:15 pm

The best place would be where the spark plug is located, but that creates a whole new set of problems. Real estate is already in short supply in the combustion chamber it's going to be difficult to find space for the injectors.

jinx44 · #4 Post by **jinx44** » Wed Sep 12, 2007 5:07 pm

Combustion swirl will come into play as well. Correctly mixing the fuel/air will be a major hurdle to overcome.

Look at a diesel piston. They are shaped like that for a reason.

cannondale27 · #5 Post by **cannondale27** » Thu Sep 13, 2007 3:22 pm

Yes this is true.Piston would need a chamber in it.

wayneschofield · #6 Post by **wayneschofield** » Tue Nov 06, 2007 1:38 am

Petrol DI causes a whole host of problems, not least of which the intake gets badly coked up.

Mitsubishi gave up with their GDi.

Power is lost due to lower volumetric efficiency because the fuel doesn't lower the intake temp and increase intake density. Proper engines have the injectors spraying down the end of the trumpets for this very reason....

Very minor benefits too, mainly just lower emissions.

cannondale27 · #7 Post by **cannondale27** » Tue Nov 06, 2007 1:41 am

It sure is interesting though.Waiting for the so called benefits though.

m_mcgranahan · #8 Post by **m_mcgranahan** » Fri Nov 16, 2007 12:53 am

Hi
I was under the impression that a couple of years ago Nissan went DI on the 350z (Or altima) and was bosting something like 20% mor epower w/ better fuel economy. This is all from recollection, but worth some research if you have time.

QUOTE (cannondale27 @ Nov 6 2007, 01:41 AM) <{POST_SNAPBACK}>

It sure is interesting though.Waiting for the so called benefits though.