Fuel Cut-off at red line

jpalmer51 · 10-13-2006, 01:16 PM

hey, I have a MT and wondered when I redline, I feel the engine lose power from the fuel cut-off, but does this do damage to the engine, or does this feature prevent damage from over-reving?

kingbriani · 10-13-2006, 01:19 PM

Quote:

Originally Posted by jpalmer51

hey, I have a MT and wondered when I redline, I feel the engine lose power from the fuel cut-off, but does this do damage to the engine, or does this feature prevent damage from over-reving?

it prevents damage. but if you didnt know, why were you bouncing it off redline??

jpalmer51 · 10-13-2006, 01:34 PM

Quote:

Originally Posted by kingbriani

it prevents damage. but if you didnt know, why were you bouncing it off redline??

well I dont try and exceed the redline, this is my first manual car so Im not the best at shifting right before redline

. But when it does happen I just want to make sure I dont do damage, so far its only happened twice.

sstarch1 · 10-13-2006, 02:32 PM

Ive been wondering something similar..with the HP and Torque curves for the 335 showing the HP and Torque tapering down twoards the redline...for best performance is it best to shift sometime before hitting the RL..it just doesnt seem natural and the difference in performance is very hard to tell since at redline in any gear you are already going very fast and everything is a blur, but what do you guys think?

citkane · 10-13-2006, 02:51 PM

Quote:

Originally Posted by sstarch1

Ive been wondering something similar..with the HP and Torque curves for the 335 showing the HP and Torque tapering down twoards the redline...for best performance is it best to shift sometime before hitting the RL..

From the curves, shifting around 6500rpm seems to be the most effective.

whippersnapper · 10-13-2006, 02:52 PM

it will be an ignition cutoff won't it? The limiter comes in pretty hard soon after redline. I have been caught a couple of times on the 1-2 change

BoostedBMW · 10-13-2006, 02:59 PM

Even though, peak HP might taper off by redline, usually you will achieve the fastest acceleration when you bring the car to redline and shift since you will have the car higher in the RPM band in the next gear when you get back on the gas.

sstarch1 · 10-13-2006, 03:24 PM

Is it possible that the shift will put you too far past the meat of the power band of the 335....?

whippersnapper · 10-13-2006, 03:41 PM

You need the thrust curves to tell. With these you can optimize the shift point for each gear change this way. For some vehicles redline is the way to go for other shifting earlier is faster

10-13-2006, 01:16 PM	#1
jpalmer51 Enlisted Member 3 Rep 34 Posts Drives: '09 335i Join Date: Aug 2006 Location: Windsor, On iTrader: (0)	Fuel Cut-off at red line hey, I have a MT and wondered when I redline, I feel the engine lose power from the fuel cut-off, but does this do damage to the engine, or does this feature prevent damage from over-reving?
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10-13-2006, 02:32 PM	#4
sstarch1 From Russia With Boost 37 Rep 1,076 Posts Drives: E92 335i - Vroom Join Date: Jul 2006 Location: Alexandria, VA iTrader: (0) Garage List 2007 335i [0.00]	Ive been wondering something similar..with the HP and Torque curves for the 335 showing the HP and Torque tapering down twoards the redline...for best performance is it best to shift sometime before hitting the RL..it just doesnt seem natural and the difference in performance is very hard to tell since at redline in any gear you are already going very fast and everything is a blur, but what do you guys think? __________________ 2007 BMW 335i - Delivered 9/8/06 Sparkling Grpahite with Black Leather/Aluminum Trim Premium Package, Sports Package, Comfort Access.
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10-13-2006, 02:52 PM	#6
whippersnapper Captain 23 Rep 972 Posts Drives: people mad Join Date: Jun 2006 Location: Atlanta iTrader: (0) Garage List 2006 BMW 325i [0.00] 2006 BMW 325i [0.00]	it will be an ignition cutoff won't it? The limiter comes in pretty hard soon after redline. I have been caught a couple of times on the 1-2 change __________________ __________________________________________________ __________________ 2006 BMW 325i, Jet Black, 6MT, ZSP, Black Leather, Aluminum, Power Seats, Logic 7
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10-13-2006, 02:59 PM	#7
BoostedBMW Moderator 133 Rep 6,775 Posts Drives: TiAg E92 335 Join Date: Oct 2006 Location: Raleigh, NC iTrader: (14) Garage List 2003 S2000 [0.00]	Even though, peak HP might taper off by redline, usually you will achieve the fastest acceleration when you bring the car to redline and shift since you will have the car higher in the RPM band in the next gear when you get back on the gas.
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10-13-2006, 03:24 PM	#8
sstarch1 From Russia With Boost 37 Rep 1,076 Posts Drives: E92 335i - Vroom Join Date: Jul 2006 Location: Alexandria, VA iTrader: (0) Garage List 2007 335i [0.00]	Is it possible that the shift will put you too far past the meat of the power band of the 335....? __________________ 2007 BMW 335i - Delivered 9/8/06 Sparkling Grpahite with Black Leather/Aluminum Trim Premium Package, Sports Package, Comfort Access.
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10-13-2006, 03:41 PM	#9
whippersnapper Captain 23 Rep 972 Posts Drives: people mad Join Date: Jun 2006 Location: Atlanta iTrader: (0) Garage List 2006 BMW 325i [0.00] 2006 BMW 325i [0.00]	You need the thrust curves to tell. With these you can optimize the shift point for each gear change this way. For some vehicles redline is the way to go for other shifting earlier is faster __________________ __________________________________________________ __________________ 2006 BMW 325i, Jet Black, 6MT, ZSP, Black Leather, Aluminum, Power Seats, Logic 7
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