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Discussion Starter #1
Ok, I've been toying around with my "racing" starts recently and I can't seem to find a perfect compromise. Either i simply shove my foot down on the accelerator about .5 seconds before i release the clutch, which certainly works well but it skids the tires so the car stops for a second.

The other method that works is revving it to anywhere above 3000 RPMs, and then jamming the gas as i slowly let out the clutch. This is probably the best way result wise, but it also seems to burn the clutch on some occasions and is very inconsistent.

so, in light of all this, how does everyone get their best/quickest off-the-line starts? (i have a 330xi, so the more specific to this, the better.)

thanks.


also, is it normal that my car seems SIGNIFICANTLY slower in the recently 20 degrees F warmer weather? i know hotter temperatures make for slower acceleration, but it's almost too much for me to believe.
 

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for me dropping the clutch is too inconsistant. Too often it will lead to bog (the pause you were talking about), so I feather the clutch. I rev to about 3-3500, and then drop the clutch to the contact point and then feather from there. If you feather it too slowly, you'll just get a lot of noise and you'll burn your clutch out quickly. But if you play around with it and practice, it'll send your head back. Have fun!
 

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Head-In-Sand Dumbass
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I concur, the warmer (thus less dense) air is severely cutting down on my car's performance! But the increased handling is nice... :)

Feathering the clutch will almost always lead to better off-the-line starts, unless you're at the track and running w/ slicks or something like that. It will also cause the most pain to your clutch, so be careful. You should make it a fast yet precise movement, yet not too fast that you're dropping the clutch. I use a +/- foot motion for the accelerator/clutch respectively, pushing on the accel. more as I let the clutch out with a linear motion past the engagement point. Once I get right past the engagement point I've started to move and I floor it, and the car takes off with no wheel spin at all.

It takes a while to master but you'll get it.

When was the last time you saw an e46 doing a burnout anyhow? I let about 10 people witness it on my commute to work the other day. :D
 

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I switched to 94 octane sunoco (what the hell, it's only 7 cents more a gallon) and found that a lot of the warm weather power loss was alleviated. I think pre-ignition may also be an issue with all the heat. I also suggest disconnecting your battery for about 15 seconds to reset the fuel maps. The engine will run a good deal richer which helps a LOT.

As for starts, I usually rev to about 2500, slowly engage the clutch, hammer the throttle (revs climb to 3500 or so), and let the clutch fly. At first I was REALLY inconsistent, but now I can do it easily. If you're doing it quickly enough, it should not burn the clutch, unless revs climb to 4K plus RPMs.
 

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Discussion Starter #5
thanks

yeah, that's pretty much what i do, though i'm always a bit confused about this:
I'm feathering the clutch and then JUST before engagement I JAM the gas. the revs go to about 6000 RPMs, yet the car just sits with the engine spinning for what is in reality probably about 1.5 secs, and then it goes; very odd. If i do get it in the right RPM range though, it sure does kick!! gotta love it, makes me smile every time. :)

lastly, where/how exactly do i disconnect the battery?

thanks so much!
matt
 

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Head-In-Sand Dumbass
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If your engine is revving and your car is not moving and your wheels are not spinning, that is NOT good. =)

That would be your clutch spinning against the pressure plate but not catching. Burning instead. Again, not good.
 

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I partially engage the clutch (usually at about 2500 RPMs) before I hammer the throttle. I NEVER go higher than 4K. If you get the timing right when you release the clutch (literally just get your foot off the pedal), the car should stay between 3000 to 4000 RPMs until the gear fully engages. This is the best compromise I've found between speed and smoke. Go a little higher and you get scent 'o clutch through the A/C.
 

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Oh yes... One other thing... Bimmers have pathetically weak clutches. At about 2200 miles, I loaned my car to my father and he blew the clutch trying to engage on a hill in third gear. (For someone who has been driving stick for 30 years, he sure sucks at it.)
 

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Head-In-Sand Dumbass
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Nick I know that was a PITA, but everytime I hear that I can't help but crack a smile. :p
 

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It makes me smile, too, now. I wouldn't be smiling if he hadn't paid for the repair, though.:p $1400! :eek:
 
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