There is a racer named Brian Smith who is running GT-40 heads and a Cobra intake. I am not sure what he is running but it's really fast and with speed density. He is at
www.stangcrazy.com. 
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86 GT T-tops, AOD, B&M shift kit and hammer shifter, ROH wheels, K&N, Timing,MAC headers, 2.5 off road H, 2.5 American Thunder, 87 spindles, rear disc,SS lines, BBK 1.5, poly bushings, Crutchfield front kick panel speakers.