Nitrous. Biggest shot for a 318

Start with a 150 shot, back up the total timing, and a NGK plug, with a NON extended nose. Then you can start adding some timing, a little at a time, keeping an eye on the plugs, and the mph. You do not want to start detonating. After you get the best tune possible, then add one step bigger nitrous jet, and go through the same process. Then just keep going one jet size at a time larger. Keep the nitrous jet one or two sizes larger then the fuel jet (after you get the initial tune.) . I am basing this on a fuel pressure of 6 lbs (flowing), and 950 nitrous pressure.

Last time out with my Barracuda we had about a 195 shot, going 13.0's. If we don't get rained out, tonight, I will try one step larger at about 212 shot, looking for 12's. This is on a stock short block 170 slant six.
PS: I run C -12 fuel.