still cant decide : auto or manual
07-17-2003, 03:57 PM
#31
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Gas mileage in many cases does matter how fast your engine is turning...at 1500rpm in an LS1 going say 55mph in 6th gear vs turning 2700 rpm in 4th gear...going in 6th you'll get better mileage PERIOD because you're dumping fuel in there at almost twice the rate...other things such as throttle position and fuel pressure also play a role in gas mileage...RPMS play a role in mileage.
07-17-2003, 04:13 PM
#32
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Originally posted by IrocManiac
Gas mileage in many cases does matter how fast your engine is turning...at 1500rpm in an LS1 going say 55mph in 6th gear vs turning 2700 rpm in 4th gear...going in 6th you'll get better mileage PERIOD because you're dumping fuel in there at almost twice the rate...other things such as throttle position and fuel pressure also play a role in gas mileage...RPMS play a role in mileage.
Gas mileage in many cases does matter how fast your engine is turning...at 1500rpm in an LS1 going say 55mph in 6th gear vs turning 2700 rpm in 4th gear...going in 6th you'll get better mileage PERIOD because you're dumping fuel in there at almost twice the rate...other things such as throttle position and fuel pressure also play a role in gas mileage...RPMS play a role in mileage.
07-17-2003, 04:17 PM
#33
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When you let off the gas you still CONSUME gas...
I obviously don't need to argue this anymore..
I obviously don't need to argue this anymore..
07-17-2003, 04:32 PM
#34
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Originally posted by WhoBetter?
It does not, your engine can be going 2500 and be using less gas than when it's going 1500. It's called air to fuel ratio. Your engine speed only depends on what gear your in and how fast your going, how much gas your feeding it has little to do with it. It's like when you let off the gas, your engine is still going 2500 rpm but it's comsuming no gas because the is has the momentum of the car to keep it going.
It does not, your engine can be going 2500 and be using less gas than when it's going 1500. It's called air to fuel ratio. Your engine speed only depends on what gear your in and how fast your going, how much gas your feeding it has little to do with it. It's like when you let off the gas, your engine is still going 2500 rpm but it's comsuming no gas because the is has the momentum of the car to keep it going.
It's obvious you don't have a clue as to what you are talking about. Maybe in a Honda civic hybrid car you can do that but a gasoline engine DOES NOT cut fuel completely just because you let off the gas. I guess I can let my car idle forever since it isn't using any gas!
07-17-2003, 04:50 PM
#35
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Why is this even a concern? I didn't buy an LS1 for gas mileage. In fact, I bought it knowing I am not getting as good of mileage as say a nice economy 4 cyl. I think this thread has run it's course.
M6's are fun to drive and will beat a stock auto.
Stalled autos are rulers at the track and will beat a M6 (equally modded of course).
Both do not get as many miles per gallon as my dream car the yugo did
LS1's are all fun!!!!!!!
WooHoo lets peeeeel out tonight baaaaby!!!!!
M6's are fun to drive and will beat a stock auto.
Stalled autos are rulers at the track and will beat a M6 (equally modded of course).
Both do not get as many miles per gallon as my dream car the yugo did
LS1's are all fun!!!!!!!
WooHoo lets peeeeel out tonight baaaaby!!!!!
07-17-2003, 06:56 PM
#36
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Originally posted by STOCK1SC
It's obvious you don't have a clue as to what you are talking about. Maybe in a Honda civic hybrid car you can do that but a gasoline engine DOES NOT cut fuel completely just because you let off the gas. I guess I can let my car idle forever since it isn't using any gas!
It's obvious you don't have a clue as to what you are talking about. Maybe in a Honda civic hybrid car you can do that but a gasoline engine DOES NOT cut fuel completely just because you let off the gas. I guess I can let my car idle forever since it isn't using any gas!
now like wise, when an a4 is interstating, you only have to give enough gas to maintain speed, same is the case with the M6. therefore there is very little difference. this is the point i'm trying to make. if you give more gas you accelerate.
very simply gas = energy, air is free
I think you all are really dense, I've got an engineering degree, i have some clue of how machines work.
07-17-2003, 08:51 PM
#37
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Originally posted by WhoBetter?
I think you all are really dense, I've got an engineering degree, i have some clue of how machines work.
I think you all are really dense, I've got an engineering degree, i have some clue of how machines work.
However, what do you mean by the following:
If you can't have both I would just keep the 3.8 because having a ls1 A4 is notmuch different than your 3.8,
I traded a 99 Firebird w/3.8L V6 A4 for my current car and the difference is pretty much like night and day.
TS
07-17-2003, 09:25 PM
#38
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Originally posted by WhoBetter?
no you idiot, when your drive train is connected to the wheels and you let off the gas, (your engine is getting no gas!) causes your car to slow down, this means there is nothing but air going thru your engine, hence your car slows down because of motor drag, this is also known as engine braking, only light if any combustion is occuring inside the engine if any sigiicant compusioin was occuring your car would not slow down,
now like wise, when an a4 is interstating, you only have to give enough gas to maintain speed, same is the case with the M6. therefore there is very little difference. this is the point i'm trying to make. if you give more gas you accelerate.
very simply gas = energy, air is free
I think you all are really dense, I've got an engineering degree, i have some clue of how machines work.
no you idiot, when your drive train is connected to the wheels and you let off the gas, (your engine is getting no gas!) causes your car to slow down, this means there is nothing but air going thru your engine, hence your car slows down because of motor drag, this is also known as engine braking, only light if any combustion is occuring inside the engine if any sigiicant compusioin was occuring your car would not slow down,
now like wise, when an a4 is interstating, you only have to give enough gas to maintain speed, same is the case with the M6. therefore there is very little difference. this is the point i'm trying to make. if you give more gas you accelerate.
very simply gas = energy, air is free
I think you all are really dense, I've got an engineering degree, i have some clue of how machines work.
07-17-2003, 09:28 PM
#39
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Originally posted by WhoBetter?
no you idiot, when your drive train is connected to the wheels and you let off the gas, (your engine is getting no gas!) causes your car to slow down, this means there is nothing but air going thru your engine, hence your car slows down because of motor drag, this is also known as engine braking, only light if any combustion is occuring inside the engine if any sigiicant compusioin was occuring your car would not slow down,
now like wise, when an a4 is interstating, you only have to give enough gas to maintain speed, same is the case with the M6. therefore there is very little difference. this is the point i'm trying to make. if you give more gas you accelerate.
very simply gas = energy, air is free
I think you all are really dense, I've got an engineering degree, i have some clue of how machines work.
no you idiot, when your drive train is connected to the wheels and you let off the gas, (your engine is getting no gas!) causes your car to slow down, this means there is nothing but air going thru your engine, hence your car slows down because of motor drag, this is also known as engine braking, only light if any combustion is occuring inside the engine if any sigiicant compusioin was occuring your car would not slow down,
now like wise, when an a4 is interstating, you only have to give enough gas to maintain speed, same is the case with the M6. therefore there is very little difference. this is the point i'm trying to make. if you give more gas you accelerate.
very simply gas = energy, air is free
I think you all are really dense, I've got an engineering degree, i have some clue of how machines work.
please, stfu- youre making real engineers look bad
but what do i know, i only worked on brakes
07-17-2003, 09:30 PM
#40
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Originally posted by WhoBetter?
you all don't understand how cars work, gas mileage doesn't matter on how fast your engine is turning, it depends simply on the power needed to push the car and what trans you have doesn't matter because the engine receives only as much gas as it needs to keep the car moving, look at any econmic car, there engines go fast but they get better mileage because there engines are smaller. as far as manual having less power loss, that is true but it's only a little, you still have most of the same gears. th M6 is a little more effcien because it has an extra gear but the differnce is not even a point to metion because what really matters is how you drive it.
you all don't understand how cars work, gas mileage doesn't matter on how fast your engine is turning, it depends simply on the power needed to push the car and what trans you have doesn't matter because the engine receives only as much gas as it needs to keep the car moving, look at any econmic car, there engines go fast but they get better mileage because there engines are smaller. as far as manual having less power loss, that is true but it's only a little, you still have most of the same gears. th M6 is a little more effcien because it has an extra gear but the differnce is not even a point to metion because what really matters is how you drive it.
an auto doesn't even have a gear, none the less "the same gears" fyi
07-17-2003, 10:51 PM
#41
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nice ride trey 
i am pretty sure you are both right kinda. when you back off the gas it does use gas but a very litle amount. thats what i have heard from many people. don't know if any of them there "engineers" though
i am pretty sure you are both right kinda. when you back off the gas it does use gas but a very litle amount. thats what i have heard from many people. don't know if any of them there "engineers" though
07-17-2003, 10:55 PM
#42
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Originally posted by mr_muff
nice ride trey
i am pretty sure you are both right kinda. when you back off the gas it does use gas but a very litle amount. thats what i have heard from many people. don't know if any of them there "engineers" though
nice ride trey
i am pretty sure you are both right kinda. when you back off the gas it does use gas but a very litle amount. thats what i have heard from many people. don't know if any of them there "engineers" though
even if the throttle is closed, air is still getting through it
he is saying NO gas is being consumed.
I am saying gas is being consumed.
how are we both right?
07-17-2003, 11:04 PM
#43
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When you back out of the throttle it uses much less gas, then running WOT. Turning more RPMS makes mileage drop if all things were equal. More RPMS at same fuel pressure, equal more fuel per minute being dumped into the motor...I stick by my original posts and this guy needs to read up on the combustion engine.
07-17-2003, 11:09 PM
#44
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Originally posted by IrocManiac
When you back out of the throttle it uses much less gas, then running WOT. Turning more RPMS makes mileage drop if all things were equal. More RPMS at same fuel pressure, equal more fuel per minute being dumped into the motor...I stick by my original posts and this guy needs to read up on the combustion engine.
When you back out of the throttle it uses much less gas, then running WOT. Turning more RPMS makes mileage drop if all things were equal. More RPMS at same fuel pressure, equal more fuel per minute being dumped into the motor...I stick by my original posts and this guy needs to read up on the combustion engine.
fuel pressure has little to do with it in a propperly tuned vehicle-
you also have to concider that at more rpms, less air is getting into the cyliders (double rpms and the time the valve is open is cut in half) there are other little things that come into play as well that I am just getting a grasp on.
according to your thoery, at cruise- gas milage should double from 4th gear to 6th gear. Id say gas milage increases 25% at best.
gas milage is not directly perportional to rpm
07-17-2003, 11:24 PM
#45
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whobetter, are you familar with kilgore ratings, these are the ratings in effiecency of automatic transmisions. If you take two identical F-bodies and one has auto the other a stick and drive them at 70 mph both going the same rpm, the auto will run out of gas first. This is because power required to turn a auto at that rpm is more than to turn the manual. This is why autos are rated at between 20 to 22% drivetrain losses and manuals at between 15 to 18%. It is important to note though that anything with overdrive gears will cosume more power in that gear than it would if it was direct drive or 1 to 1. As far as using gas when let off the throttle. Most fuel injected engines will cut off fuel if you let off the throttle and leave it in that gear to decelerate. This is because there is almost no air being pulled into the cylinder because the thottle plate is closed, and it wouldnt do that cats any good to see that much unburned fuel it would hurt emmisions. There is still a small amount of gas but only as small as the amount of air that can be pulled through closed throttle plates or the IAC.
