# 540i launch



## bmw540i (Mar 30, 2003)

On what RPM is it best to launch a manual to get the best resaults. I always take the RPM to 5 and let the clutch but the tires start spinning and i never get a good start so any help would be great.


----------



## Nick325xiT 5spd (Dec 24, 2001)

The highest RPM the tires don't spin at...

I suspect it's in the 2500 range. The 540i with it's open diff and deep torque reserve does not launch well.


----------



## AK (Jan 19, 2002)

bmw540i said:


> On what RPM is it best to launch a manual to get the best resaults. I always take the RPM to 5 and let the clutch but the tires start spinning and i never get a good start so any help would be great.


2000 RPM and sidestep/slip the clutch. Don't bother revving to 5000. The 540i has plenty of torque. Anything under 2000 and you risk bogging, anything higher than 2500 and you risk tirespin.

AK


----------



## bmw540i (Mar 30, 2003)

AK said:


> 2000 RPM and sidestep/slip the clutch. Don't bother revving to 5000. The 540i has plenty of torque. Anything under 2000 and you risk bogging, anything higher than 2500 and you risk tirespin.
> 
> AK


So you take it up to 2000 RPM hold it and then release the clutch and press the gass all the way down.


----------



## Dan Martin (Apr 3, 2003)

bmw540i said:


> So you take it up to 2000 RPM hold it and then release the clutch and press the gass all the way down.


Just make sure you can feel the difference between clutch slip and wheelspin when you sidestep the clutch because that can be costly!

Where's that infamous Camaro video when I need it.....


----------



## Greco (Feb 16, 2003)

You mean the frying your clutch priceless video?

Tried a 3000 clutch slip, and too much tire spin. I figure 2000 is more than enough with a very quick but good modulation of clutch slip and throttle position..


----------



## bmw540i (Mar 30, 2003)

AK said:


> 2000 RPM and sidestep/slip the clutch. Don't bother revving to 5000. The 540i has plenty of torque. Anything under 2000 and you risk bogging, anything higher than 2500 and you risk tirespin.
> 
> AK


I did it at 2000 RPM couple of times and it seems to be working. But couple of times the tires started to slip and the car wasnt moving. Is it wise to release the clutch at 2000 RPM wont it damage the clutch.

Thanks for all your replys.


----------



## Dan Martin (Apr 3, 2003)

bmw540i said:


> I did it at 2000 RPM couple of times and it seems to be working. But couple of times the tires started to slip and the car wasnt moving. Is it wise to release the clutch at 2000 RPM wont it damage the clutch.
> 
> Thanks for all your replys.


Well I wouldn't be doing it on a daily basis if I were you but if you need to get your times down that's the best way.

I read a Car and Driver review of a Diablo VT once and they were told that they had to rev the engine to 5000 and sidestep the clutch for a good launch. At 5000 all 4 wheels would break loose for the first 20' or so. At 4500 the wheels would stick and the clutch would be toast in an instant. Anything higher than 5500 and you'd never get traction.

You're pretty safe with the 540. The only thing that's going to happen is below 2000 your engine will lag a bit and anything over 3000 you'll have too much wheelspin to do anything useful.


----------



## bmw540i (Mar 30, 2003)

Thanks For all your replys.


----------



## Greco (Feb 16, 2003)

It's really all about modulation and "feeling" the car. Getting away quick and with minimal tirespin take some practice.

Good luck..


----------

