SFI stand for?

[2kgrandam]

just wanted to know just bought the car .

well whats SFI mean

[sunrunner_pei]

Originally posted by 2kgrandam
just wanted to know just bought the car .

well whats SFI mean

Sequential Fuel Injection.

[LoneRangers15]

I believe that fuel is sprayed into each of the cylinders individually, unlike mine where it is just sprayed into the throttle body (TBI).

[2kgrandam]

Originally posted by 2kgrandam
just wanted to know just bought the car .

well whats SFI mean

what exactly does that mean?

[sunrunner_pei]

Originally posted by 2kgrandam
what exactly does that mean?

You're asking yourself what you mean?? :wtf:

[BlackThorn]

Originally posted by sunrunner_pei
You're asking yourself what you mean?? :wtf: lol that's pretty damn funny

[GrandAmageGT]

Originally posted by 2kgrandam
what exactly does that mean?

Shawn told you...Sequential Fuel Injection = SFI!

How about this Sequential Fuel Injection

[sunrunner_pei]

For more information on how Fuel Injection works, check out http://auto.howstuffworks.com/fuel-injection.htm There is a TON of good information there, as well as many helpful links to get you started.

Here's some great info:

There are two main types of control for multi-port systems: The fuel injectors can all open at the same time, or each one can open just before the intake valve for its cylinder opens (this is called sequential multi-port fuel injection).

The advantage of sequential fuel injection is that if the driver makes a sudden change, the system can respond more quickly because from the time the change is made, it only has to wait only until the next intake valve opens, instead of for the next complete revolution of the engine.

[martopg]

Originally posted by sunrunner_pei


STOP POSTING THE SAME QUESTIONS OVER AND OVER!!!

Indeed...

[rollbonez]

Shawn,

That link was amazingly interesting, particularly the part about engine hesitation when the mixture is too lean.

I have been wondering about a brief hesitaiton in my car during hard moderate acceleration after I replaced the stock filterbox with a 7" K&N cone. I figured it had something to do with it, but could never find the scientific evidence to prove it.

Interestingly enough, if you took this explanation at face value, that would mean intake/exhaust mods to open airflow would actually hurt fuel efficiency because the car's computer would use more fuel to enrichen the mixture and even out the preset ratio.



tom


Originally posted by sunrunner_pei
For more information on how Fuel Injection works, check out http://auto.howstuffworks.com/fuel-injection.htm There is a TON of good information there, as well as many helpful links to get you started.

Here's some great info:

[rollbonez]

I found the original thread that I was discussing this theory on:

http://www.gaownersclub.com/forum/showthread.php?s=&threadid=4671

So far, everyone who has tried to sell me an exhaust system has used fuel efficiency and performance as justification.

[sunrunner_pei]

Originally posted by rollbonez
I found the original thread that I was discussing this theory on:

http://www.gaownersclub.com/forum/showthread.php?s=&threadid=4671

So far, everyone who has tried to sell me an exhaust system has used fuel efficiency and performance as justification.

I've often thought the same thing. Introduce more air, and you also have to introduce more fuel. The only other variable is that you're making the engine mroe efficient, hence you may need less throttle to produce the same results.

However, with any mod that increases performance, a heavier foot often follows, negating any fuel savings the mod may have given you. :)

[rollbonez]

ESPECIALLY in speed-crazy Southern California!


Originally posted by sunrunner_pei

However, with any mod that increases performance, a heavier foot often follows, negating any fuel savings the mod may have given you. :) [/B]

[Marks95GAGT]

How Stuff Works (http://www.howstuffworks.com) RAWKS!!! They have some cool stuff on there.

[Marks95GAGT]

Originally posted by rollbonez
Shawn,

That link was amazingly interesting, particularly the part about engine hesitation when the mixture is too lean.

I have been wondering about a brief hesitaiton in my car during hard moderate acceleration after I replaced the stock filterbox with a 7" K&N cone. I figured it had something to do with it, but could never find the scientific evidence to prove it.

Interestingly enough, if you took this explanation at face value, that would mean intake/exhaust mods to open airflow would actually hurt fuel efficiency because the car's computer would use more fuel to enrichen the mixture and even out the preset ratio.



tom


Well all things given, It might actually need less fuel to run because the engine doesn't have to work as hard to pull air into the engine. It could be look at that point of view also. But I think there is a finite value for the amount of fuel that has to be given for the engine to run. Lets say that you have a cylinder volume of 50cc's. And for a 3.1 liter motor to run at idle at about 600 rpm it may require say 3ul of fuel each time the cylinder is run. Well I think, and some one please correct me if I am wrong, that when the piston is a Bottom Dead Center both valves are closed and even thought the volume of the cylinder is at say 60cc's (including combustion volume when the piston is at TDC) the pressure in the cylinder is actually less than that of the outside atmosphere. So less than 50cc's of air is pulled into the engine for that cylinder and less then 3ul of fuel is required. But the drag of air through the filter, intakes, exhaust and valves, and the friction of all the moving parts in the motor may accually make the computer dump say 4ul of fuel. That may still be lean, but it 33% more fuel that what was dumped before. Sorry for my crazy rant and thought process.

[rollbonez]

whoa. I'm going to need a few minutes to soak this in.

:???3:


Originally posted by Marks95GAGT
Well all things given, It might actually need less fuel to run because the engine doesn't have to work as hard to pull air into the engine. It could be look at that point of view also. But I think there is a finite value for the amount of fuel that has to be given for the engine to run. Lets say that you have a cylinder volume of 50cc's. And for a 3.1 liter motor to run at idle at about 600 rpm it may require say 3ul of fuel each time the cylinder is run. Well I think, and some one please correct me if I am wrong, that when the piston is a Bottom Dead Center both valves are closed and even thought the volume of the cylinder is at say 60cc's (including combustion volume when the piston is at TDC) the pressure in the cylinder is actually less than that of the outside atmosphere. So less than 50cc's of air is pulled into the engine for that cylinder and less then 3ul of fuel is required. But the drag of air through the filter, intakes, exhaust and valves, and the friction of all the moving parts in the motor may accually make the computer dump say 4ul of fuel. That may still be lean, but it 33% more fuel that what was dumped before. Sorry for my crazy rant and thought process. :???3: :???3: