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View Full Version : Matthews or other draggers, help!


Nixlimited
Thu, Oct-14-2004, 05:08:55 PM
I think I am going to give a go at dragging my car tomorrow night for the first time. I am just curious what I should do with tire pressures out there. I am running 19's with 245/275 setup. Also, should I use Sport Mode? Anything else I should think of? Thanks for any help!

gnk2727
Thu, Oct-14-2004, 05:23:19 PM
You can use sport mode, but make sure you are comfortable with the throttle response off of the line, it may be too much, it may be just right. I see you have 6mt, so what rpm's are you planning on launching at??? Are your rims and tires stock?? If so, I would suggest going with about 38/40 front/rear. A lot will also depend on the temperature that day, cause you dont wanna set the psi too high if it's real hot outside.

MadMacs
Thu, Oct-14-2004, 05:26:53 PM
19's with 245/275 setup. Also, should I use Sport Mode?
Make sure you check PSI before you leave for the track - preferrably cold.
You will want extra pressure in front to reduce contact area - provide less front end resistance. I would probably suggest bringing a metal ruler or some other straight measure and keep your rears as square as possible - PSI really won't tell you anything. If your tread is in good shape, the reccomended pressure for rear should be close to square - and you want as MUCH contact surface in the rear as possible. As far as sport - what mode are you comfortable launching at (feathering the clutch). I tried Lee's (Mathews) high RPM launches and felt most comfortable @ 4,000 - but the rears at the time were toasted. DO spin the tires a bit - enough to clean the debris off - but there should be no need for water - drive around it. You WILL pick up debris on the return lane.

Shut EVERYTHING off - A/C fan blower - EVERYTHING. DSC=OFF!!!!

If your launch is OK you should be in WOT in no time - again Sport is up to you - I'd suggest using whatever you normally drive with.

Best of luck and take a cameraman with you :beer:

Nixlimited
Thu, Oct-14-2004, 05:53:28 PM
Thanks for the input. I normally drive in non-Sport mode so I am used to the throttle response without Sport on. Since WOT is the same in both, I should probably just go with what I know. I have no idea what my launch RPM will be since I have never done it. I will probably start at some point and work up until I am comfortable and I am getting better times.

gnk2727
Thu, Oct-14-2004, 11:37:51 PM
You may wanna start at about 3500 rpm's and work your way up from there, make sure you run high psi in your tires if ur gonna dump the clutch at higher rpm's since ur running on what appears to be stock rubber. Make sure you take out those huge subwoofers if you can.