6th gear highway
01-10-2010, 09:28 PM
#21
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^^^that post is full of stupid. Here's why. My thoughts in bold.
And as far as autos sucking, well... we can spank that *** all day at the track.
Have a nice day
I never lug my engine...if what I do to it is destroying it, then why does it have almost 180K on it, and still runs just like it's brand new?
nobody said you lug your engine. I said lugging an engine is one of the worst things you can do. And even after your rediculous post, its still true
It also gets 30 mpg on the highway all the time.
Nobody cares about this. If you are pointing out that you get better gas mileage then me or any other auto does....well
we have known this fact for a long time. You aren't the first to discover it.
Cruising over 2500 with an auto...is one of several reasons why auto's suck...once you throw a set of gears at the car, your highway RPM becomes stupid...all that 2500+ RPM is doing is generating more heat in your engine and wasting fuel.
How you take hwy rpm is up to the individual. Yes, it wastes fuel, but again stupid bc you are on a performance oriented forum, and, our cars waste no more gas then any other auto on the road
They would NOT build the car to go the RPM is goes stock at the speed limit (65 mph in most states) on the highway in 6th gear if that RPM was going to hurt it...do you work for "them"???they also wouldn't make that happen at the minimum safe RPM either. once again, who do you work for???It's not like I pull up a hill in 6th at 50congrats, you know how to drive...but if traffic slows down and the pavement is level or downhill, and I can see it picking the pace right back up, I will absolutely leave it in 6th and let come back up with mph, smoothly...because it isn't lugging.once again, congratulations
nobody said you lug your engine. I said lugging an engine is one of the worst things you can do. And even after your rediculous post, its still true
It also gets 30 mpg on the highway all the time.
Nobody cares about this. If you are pointing out that you get better gas mileage then me or any other auto does....well
we have known this fact for a long time. You aren't the first to discover it.Cruising over 2500 with an auto...is one of several reasons why auto's suck...once you throw a set of gears at the car, your highway RPM becomes stupid...all that 2500+ RPM is doing is generating more heat in your engine and wasting fuel.
How you take hwy rpm is up to the individual. Yes, it wastes fuel, but again stupid bc you are on a performance oriented forum, and, our cars waste no more gas then any other auto on the road
They would NOT build the car to go the RPM is goes stock at the speed limit (65 mph in most states) on the highway in 6th gear if that RPM was going to hurt it...do you work for "them"???they also wouldn't make that happen at the minimum safe RPM either. once again, who do you work for???It's not like I pull up a hill in 6th at 50congrats, you know how to drive...but if traffic slows down and the pavement is level or downhill, and I can see it picking the pace right back up, I will absolutely leave it in 6th and let come back up with mph, smoothly...because it isn't lugging.once again, congratulations
Have a nice day
01-11-2010, 09:14 AM
#22
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"Let me ask you this, what RPM do you turn at 35-40 mph? What gear do you let the car use? If it's a stock gear T56 car, that speed should be in 5th gear."
remember that 5th gear has a lower gear ratio (numerically higher), which means the mechanical advantage is greater. so 1200 rpm in 6th may lug the engine down, but 1200 in 5th is no problem.
remember that 5th gear has a lower gear ratio (numerically higher), which means the mechanical advantage is greater. so 1200 rpm in 6th may lug the engine down, but 1200 in 5th is no problem.
01-11-2010, 09:28 AM
#23
Hmm... I have driven my fair share of m6's even though mines an A4... What I have found is if you KNOW how to shift and drive, 3rd gear starts are easy, and the engine has more then enough power in 6th gear to drive quite nice and smooth at 55 mph..... hovering around 1400 RPMS.... If your on a flat stretch of road, I don't see how basically letting your engine IDLE in 6th gear could be harmful for it.... When is the last time you heard of someone blowing their engine for "undereving" it... Then again maybe all that extra damn driving school and driving endorsements I had to study for and get at my last job taught me wrong....
01-11-2010, 09:32 AM
#24
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all other drive line parts being stock....55mph = 1200rpm
i can def feel a difference between 6th at 1200 rpm and 1500rpm...would seem like much...but i can.
i can def feel a difference between 6th at 1200 rpm and 1500rpm...would seem like much...but i can.
01-11-2010, 09:49 AM
#25
Yes it would be if all other parts are stock.... When I was driving this NBM 2001 SS I had it between 1200-1500 rpms in 6th, at 55 I basically was letting it idle... I should be more descript, I forget people don't know whats actually going on in my head...
01-11-2010, 08:38 PM
#27
"Let me ask you this, what RPM do you turn at 35-40 mph? What gear do you let the car use? If it's a stock gear T56 car, that speed should be in 5th gear."
remember that 5th gear has a lower gear ratio (numerically higher), which means the mechanical advantage is greater. so 1200 rpm in 6th may lug the engine down, but 1200 in 5th is no problem.
remember that 5th gear has a lower gear ratio (numerically higher), which means the mechanical advantage is greater. so 1200 rpm in 6th may lug the engine down, but 1200 in 5th is no problem.
You didn't.
01-12-2010, 07:27 AM
#28
A magazine, Automobile, R&t, one of those addressed this specific issue in their technical correspondance column. Their conclusion from talking to automotive engineers was that "lugging" a manual trans was harder on the transmission than the engine. Apparantly, "lugging" (rpm too low for road speed) causes rattling/harmonics in the trans that are destructive to it. Any trans mechanics out there that have first hand experience with this?
01-12-2010, 07:50 AM
#29
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A magazine, Automobile, R&t, one of those addressed this specific issue in their technical correspondance column. Their conclusion from talking to automotive engineers was that "lugging" a manual trans was harder on the transmission than the engine. Apparantly, "lugging" (rpm too low for road speed) causes rattling/harmonics in the trans that are destructive to it. Any trans mechanics out there that have first hand experience with this?
01-12-2010, 08:33 AM
#30
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OK Not gonna get on here and say that i'm an expert at engines or trans or driving!
Just make-n the statement that before I put 4.10's in the rear of my car I never used
6th gear unless I was speeding at 80mph!......anything less felt like it was almost lugging!
& I'm still only 2000rpm's @ 70mph!!
Just make-n the statement that before I put 4.10's in the rear of my car I never used
6th gear unless I was speeding at 80mph!......anything less felt like it was almost lugging!
& I'm still only 2000rpm's @ 70mph!!
01-12-2010, 02:01 PM
#33
A magazine, Automobile, R&t, one of those addressed this specific issue in their technical correspondance column. Their conclusion from talking to automotive engineers was that "lugging" a manual trans was harder on the transmission than the engine. Apparantly, "lugging" (rpm too low for road speed) causes rattling/harmonics in the trans that are destructive to it. Any trans mechanics out there that have first hand experience with this?
You really aren't lugging an LS engine unless you were either crusing below 1,000RPM or running a very low RPM (1000RPM-1400RPM) with a high throttle % position.
01-12-2010, 09:27 PM
#34
EXACTLY
01-12-2010, 10:35 PM
#35
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1900!! 
jeezus man!
50mph is ~1100rpm in 6th assuming stock rear/tires
55mph is 1200 which is where i draw the line. although even with a cam the car still moves along just fine on flat land at that speed.
if you're just on the highway...why would you wait till 70 to shift to high gear? why on earth would you WANT to run the car at 2200rpm when you can run at a nice smooth/quiet/efficient 1500rpm??
jeezus man!
50mph is ~1100rpm in 6th assuming stock rear/tires
55mph is 1200 which is where i draw the line. although even with a cam the car still moves along just fine on flat land at that speed.
if you're just on the highway...why would you wait till 70 to shift to high gear? why on earth would you WANT to run the car at 2200rpm when you can run at a nice smooth/quiet/efficient 1500rpm??
01-12-2010, 11:19 PM
#36
01-12-2010, 11:26 PM
#37
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a pretty good experiment to test the 5th vs. 6th gear efficiency do alittle experiment the next time your cruising along in 6th at a low rpm,,, with out changing the amount of throttle you have, just keep the right foot pressure constant on the gas pedal, downshift to 5th and ease the clutch out. dont be surprised to find the car accelerating with the same throttle input. this means that you can cruise at a slightly higher rpm using less throttle input (less gas=higher mpg). I try not to drive in 6th at anything less than 1500 rpm just for fuel milage reasons, simply put it takes more gas to produce the power to accelerate the car at a lower rpm (because of the lower mechanical advantage) than it does at a moderately higher rpm. the sweet spot for me is about 2100 rpm, 6th gear about 78-80 mph = best mpg,,, supposedly its the "sweet spot" in the rpm range for a stockish LS1.
Im surprised no one has brought up the obvious reason you shouldn't "lug" your engine,,,, DETONATION!! putting to much of a load on an engine at a low rpm is a primary cause and has horrible consequences to the internals!!
Im surprised no one has brought up the obvious reason you shouldn't "lug" your engine,,,, DETONATION!! putting to much of a load on an engine at a low rpm is a primary cause and has horrible consequences to the internals!!
01-12-2010, 11:56 PM
#39
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I certainly agree with your first post though. I didnt go into detail about the inner workings of an engine and why exactly its not good to "lug" it. But basically its like detonation, although you dont see this, doesnt mean its not hurting the engine in the long run.