The track will be well prepped, so you should get away with leaving your tyre pressures where they are. But if you find yourself getting wheel spin of the line, take out 1-2 psi of all 4 wheels, until you get it to hook up right off the line. Don't go any lower that about 26 psi though & pump them up at a servo as soon as you can on your way home.

I went down to about 25 lb last Wed and got a bit of track skate mid track (slight left / right slide movement), so be careful driving once you have let them down.

Because its well prepped, you should be able to launch harder than 4 k, but work your way up to it. You should be aiming for 5.5 to 6 k launches & from previous experience a 1.9X 60 ft should be attainable. What I have found is that every .1 of a second on the 60 ft time is around .2 of a second on the 400m time. You do need to launch them hard, but do it carefully.

I don't have DCCD, but I was there when a guy was using it one night. Believe it or not he got a better time by leaving it in Auto, but this may have been a coincidence.

Only try to make a single change at a time (tyre pressures), if you start changing too much in one go (tyre pressures & launch rpm) you might not be able to see what has actually increased / decreased your time.

One more thing is that while it is fun to race against the car next to you, the reaction time does not count in your 400m run. If you are only going down to get a good time, you can relax a bit more on the line and launch after the next to you has. This way you can pay more attention to your launch rpm, unless you have launch control?

Last thing I would say is, as a start point for your first run, tyre pressures at 30 lb, DCCD in auto & launch at 5k. Hope that is of some use, if you want to ask any other questions, feel free to mate

__________________
Cheers,

Simon.