[petesamprs]

I just passed break in and wanted to open her up a bit more. Does it damage the engine to go up to 7k rpm before shifting? How bad is this for the car if done repeatedly?

Also, what's the downside of riding down the highway in 4th at 4k rpm vs. 6th at 3k rpm (I've found a 500rpm difference per gear at same speed). I find 6th useless and like the power readily available in 4th, but feel like its bad to keep the engine RPMs at 4k+ consistently for miles and miles on a highway.

[shimshimhada]

If you want to go as quick as possible, shift just before the redline.

6th gear is there to cruise and increase your MPG.

[success]

its not bad for the car necessarily, you'll just suffer gas mileage. and runs up to 7k are not gonna damage anything just dont downshift to a gear that would take you past 7k

[LEDZEP]

I agree with the other replies. But I must correct the title of the thread. It should be: The proper RPM at which to shift. You shouldn't end sentences or thread subjects with a preposition.


Sorry, can't help it. English is a disease. I only wish it were contageous!


P.S. Hey ShimShim... that's a fine looking photo in your sig!

[Compos Mentis]

Originally Posted by LEDZEP

. I only wish it were contageous!

Do you mean contagious? Physician, Heal Thyself!

[mjh93sa]

As stated - you'll notice the difference through your wallet at the pumps.

If it was going to be a problem BMW wouldn't put a warranty on the car, or they would lower the rev limit. Part of the test cycle that any manufacturer will put a vehicle through is to start the car (or bike) and take it straight to the redline, repeatedly, just to make sure it can.

If you want to get the best life out of the car just remember to let it warm through first. Then as importantly, before you finish your journey ease up on it and let the engine start to cool. Constant thermal cycles will cause fatigue.

OT a bit, but from my area of training - Piston engined aircraft will suffer cracked blocks purely from incorrect thermal handling - lots of power when climbing and cruising, then none (if improperly handled) whilst the aircraft descends so the block cools suddenly and rapidly, stresses are highlighted and exhaust manifolds and blocks are known to crack under this stress.

Obviously you aren't creating the same extremes, but running the engine at high rpm will create a lot of heat through friction. Stop in a snowbound zubzero carpark and you are then relying on the thermal insulation of the engine bay to protect the engine.

[ON325i]

Use Curise Control on Highway. That is where mileage are saved!

[David328M-Sport]

Originally Posted by LEDZEP

You shouldn't end sentences or thread subjects with a preposition.

A lot of people tend to do that but.

[shimshimhada]

Originally Posted by David325Australia

A lot of people tend to do that but.

"But" isn't a preposition, it's a coordinating conjunction.

[parafrog]

Originally Posted by Compos Mentis

Do you mean contagious? Physician, Heal Thyself!

[cntlaw]

Your car user manual should show the max. speed for each gear. When the max. speed of a gear is reached, your car will not be any faster until up shift to next gear. You will not damage your gearbox by going to redline, however, if you stay in a low gear (2,3) for a continuous longer period of time under high torque , some components of your gearbox is subject to a higher deteriation rate.

This does not mean you should avoid to drive in low gears at their max. speeds. BMW is well known to be driven as hard as you can. After your break-in period, you should increase the number of occasions of going to redline for every gear. A wild horse must be beaten !

[poldim]

Originally Posted by LEDZEP

I agree with the other replies. But I must correct the title of the thread. It should be: The proper RPM at which to shift. You shouldn't end sentences or thread subjects with a preposition.


Sorry, can't help it. English is a disease. I only wish it were contageous!


P.S. Hey ShimShim... that's a fine looking photo in your sig!

I sincerely enjoy you correct the grammar on this board, or lack there of....



At any rate, as long you are shifting before redline, then you arent doing excessive damage, however, thats not to say that by doing so you wont break something. The more load you put on the engine, the more ware that it ultimately encounters...

[fredtoo]

Dive a car with an automatic transmission and a tachometer.
You will see that when you are beating on it, the car will shift at or near redline. When you are driving like a granny, the car will be shifting at about 2000 RPM.

Do the same thing with a stick.

[BMW Enthusiast]

Originally Posted by LEDZEP

I agree with the other replies. But I must correct the title of the thread. It should be: The proper RPM at which to shift. You shouldn't end sentences or thread subjects with a preposition.


Sorry, can't help it. English is a disease. I only wish it were contageous!


P.S. Hey ShimShim... that's a fine looking photo in your sig!

You should not send out messages without checking your spelling.

Sorry, can't help it. Spelling is a disease. I only wish it were contagious!

[LEDZEP]

Originally Posted by Compos Mentis

Do you mean contagious? Physician, Heal Thyself!

I never said I could spell!

[timoth31]

This is exactly what drives me nuts about the lack of a coolant temperature gauge. In any other car I could check to see that the block wasn't heating up rapidly enough to produce thermal fatigue and premature wear on the block and/or cylinder heads. With my 330i it's pure guesswork. My engineering professors wouldn't tolerate that. The Navy wouldn't tolerate that. Why the hell does BMW?

[Compos Mentis]

Originally Posted by timoth31

This is exactly what drives me nuts about the lack of a coolant temperature gauge. In any other car I could check to see that the block wasn't heating up rapidly enough to produce thermal fatigue and premature wear on the block and/or cylinder heads. With my 330i it's pure guesswork. My engineering professors wouldn't tolerate that. The Navy wouldn't tolerate that. Why the hell does BMW?

It's because most people aren't engineers.
CM

[jbl16]

During normal driving on my 330i I shift at around 3000-3500 rpms.

[ward]

Originally Posted by timoth31

This is exactly what drives me nuts about the lack of a coolant temperature gauge. In any other car I could check to see that the block wasn't heating up rapidly enough to produce thermal fatigue and premature wear on the block and/or cylinder heads. With my 330i it's pure guesswork. My engineering professors wouldn't tolerate that. The Navy wouldn't tolerate that. Why the hell does BMW?

it's been pure guesswork for quite a few years now,
the BMW temp guages are damped so that they only read in the middle unless there's a major problem.

if you were running just a bit hot or just a bit cold you would have no idea with a modern BMW temp guage

too many people were bringing the cars in to dealers because they didn't understand the guage, so they took it away

[Driv3r]

When driving normally, I actually shift at around 2700 (2750rpm=325i TQ Peak )

but honestly can anyone justify the shifting at redline statement? I know that the 330i cranks 255 at 6600rpms but for a 325i the horsepower actually drops after 6250rpm if anyone here hasnt felt that "overreving" feeling when passing HP peak...That said where should 325i owners shift at?

[petesamprs]

Originally Posted by Driv3r

When driving normally, I actually shift at around 2700 (2750rpm=325i TQ Peak )

but honestly can anyone justify the shifting at redline statement? I know that the 330i cranks 255 at 6600rpms but for a 325i the horsepower actually drops after 6250rpm if anyone here hasnt felt that "overreving" feeling when passing HP peak...That said where should 325i owners shift at?

Thanks for the help guys. This helps with a related follow up question I had. What is the OPTIMAL rpm to shift at in each gear if you want to accelerate quickly? It is the RPM where the torque curve is peaked? Where the HP is peaked? Does that peak apply to all gears the same?

Some are saying its where the torque/HP curve peaks, some are saying redline, some saying what the manual says....

Forgive me, just don't know much about it.

[LEDZEP]

Originally Posted by ward

too many people were bringing the cars in to dealers because they didn't understand the guage, so they took it away

That's scary! Based on the things people around here don't understand, there won't be many components left in the next generation BMW!!