Bigpower

Been reading a bit recently about this following on from the RWYB day at Santa Pod to see what is the most efficient way of launching quickly.

I'm thinking that launching at or around the peak torque revs is the most efficient way - Does anyone have any other views?

I found the best launch on mine was about 5500 (just over peak torque), any thing lower and it would bog down a little, with a smooth quick dump of the clutch. Controlling/judging the spin is the hard bit. This will all change on different surfaces/conditions.

It depeneds on the surface. You will need to launch at the revs you find traction.

Its gonna depend on

- track temp
- track prep
- tire temp
- tire pressure
- lag if any
etc

I find traction at 1500 rpm - but that doesnt mean it is the quickest though Scott

When You drop your tire pressures and go on a sticky track you will need to alter the revs.
I think from memory that you need to slip 1.5 rotations per 1 actual rotation

There is no point reving beyond this point and spinning like a loon.

You would be very surprised to know what i launch at on road tires

Scott

If you can tell me how to post a excel file i will give you a datalog in .txt format of a drag run

Scott

sdminus wrote:If you can tell me how to post a excel file i will give you a datalog in .txt format of a drag run

Scott

hmm - dunno will try and figure out a way

http://www.sharebigfile.com/file/24375/ ... r.xls.html

Try this link. You have to stick the number in as displayed for some reason

The link is from a log taken from jap show. 12.2 @116mph

I have removed sensitve info from the datalog so some info is missing.

From 374 m/s to 400.968 m/s the car is staging etc

400.968 the car leaves the line.

402.765 m/s i start the shift to second gear and complete the change by 403.046 which is where the throttle is going down again.

404.828 m/s i start to shift to 3rd gear. Completed by 405.093 m/s

407.437 m/s i start to shift to 4th ( final shift ) comlpleted by 407.718

413.203 the car crosses the line

You will see that the car departes the line on boost
4537 RPM 1st gear @ 0.7 BAR with 87 % throttle. I catch the clutch on the up sweep in the revs

As the rpm climbs the wheels are slipping. This can be seen by the boost level droping as the load drops. It takes almost 1 second for me to correct this.

I dont normaly do this or share info of this type.

The log reads from top to bottom. the title for each set is at the top of the colum

I had a transbrake fitted but haven't had a chance to use it yet, expecting the launches to be a lot better

I find the best launches are the ones done by someone else...

There is always something you would like to improve... I guess thats what keeps it interesting

JC