How much tire pressure in DR's?

[Bundmar]

Im running my car on BFG G FORCE DRAG RADIALS at the track and need to know how much pressure I should drop in the tires I was thinking 15PSI and also how long of a burnout should I do to heat up the tires, and what can I launch at?
thanks,

 

[lvmustanggt]

I have Nitto 555R 275/40/17 and at the track I use 15 psi

I launch around 3000 RPM, I do like 10-15 sec burnout

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