What "injection" if any?

adr3naline fix · 03-08-2006

What "injection" if any? All I see these days is Injections for your car. Methanol, Alcohol, water, of course Nitrous. and what not.

I opened up my Muscel Mustangs and fast fords and the first thing i see is somthing about methanol injection.

IF I were to do any of these, which would be the best for your car while still having a nice increase in performance?

thanks!

engineer76 · 03-09-2006

If your car is not running a type of forced induction, you don't need any kind of injection besides a Nitrous setup.

Here is why:

1. Fuel Injection:

Nowadays all new cars have fuel injection. just a different setup than a carburetor but it does the same- mixing fuel into the air.

2. Alcohol/ water injection (cooling & pre ignition)

Alcohol/water (Methanol & Ethanol which are both alcohols), and pure water injection and any combinations have one reason.
Forced induction always rises the air temperature. An intercooler can lower the temperature of the air again.
How ever, if the boost and temperature of the air exceeds a certain limit, you get pinging. that's when the mixture self ignites without the use of a spark.
To prevent that from happening, you can spray water into the air, because water does two things.
1st it cools down the temperature of the air because of the evaporation energy being absorbed
2. it actually rises the mixture's octane rating.
The only problem is that water does not burn and therefore has no additional energy in it to set free.
That's when the water/alcohol about 50%/50% mixture has it's advantage. It actually burns the part of alcohol, but it cools just a little less than pure water. Methanol or Ethanol it does the same.

3. Alcohol as a fuel:

The other application is to use alcohol pure as a fuel.
This has huge advantages but also disadvantages.
Advantage: Alcohol has a way higher octane rating as gas. Therefore you can actually jack up boost way over a gas powered motors limits and you will still not have any pre ignition.
So instead of running a turbocharged car at a stock 14 PSI boost with gas, you can run the same motor at 22 PSI of boost without any problems. The trade off is, that you have to run way lower A/F ratio. instead of the 12.5-14 for a gas powered motor, you have to run around 8-9.
That's because of the lower heat value 43 MJ/kg gas, versus the 26.8 MJ/kg of ethanol (methanol is even worse). Obviously with the higher boost and the lower A/F ratio you have to get huge injectors, or for a carbureted motor huge jets and venturis.
Fuel pumps have to get upgraded too, and obviously the ECU reprogrammed.
The good point is that you can easily get about 30-50% more HP out of a motor than with gas

http://journeytoforever.org/biofuel_library/ethanol_motherearth/me1.html

4. Nitrous oxide injection

Nitrous does 2 things.
1. when expanding after being compressed, like all gases, it becomes real cold. this cools down the air fuel mixture and provides the motor with a more dense air.
2. The other effect is that nitrous oxide consists out of nitrogen and oxygen. At a the temperature of the combustion, this chemical compound falls apart and additional oxygen is set free in the combustion chamber.
correcting the lack of fuel with additional fuel, brings the air fuel ratio back to a safe level.
These two effects work hand in hand:
A motor is capable of burning (per revolution) more fuel, completely, although the volumetric efficiency of the motor did not change at all.

adr3naline fix · 03-09-2006

Did you write that all?

Thats amazing

Its funny because I am just learning about all of the Ethonal, Methanol/ Joules and their burning tendancies and points in chemistry this past week.

The whole situation with an "injected performance" is still a little touchy in my household. My dad is one of those people that has a nice car (2003 BMW 330Ci) and thinks that all of these kids trying to do things to their cars are retarded.

Im betting that the sound of me saying Nitrous Oxide to him and being serious is going to get a very interesting reaction. It just seems like somthing you would see in a movie.

Thank you very much for the information. I really appreciate it/.

engineer76 · 03-10-2006

Yep! was all me!

You see, if someone is asking for info I like to help anybody out with what I know.
My personal goal is to have a Mustang board with lots of good information, and smart people who wont even bother about, if someone says that yellow spark plug cables can give you an extra 40 HP.
I think it is very sad to look at other boards (civic, camaro, etc. - others unmentionned) and not being able to get any valuable information besides "fights and flaming"

adr3naline fix · 03-10-2006

thats very true.

everyone on this board should have a mindset just like yours