There's a couple threads out there that did dyno's, semtex for one, as I recall.
5-6 whp is what you can expect, which is a very impressive cost to hp ratio.
I noticed the responsiveness more than any hp gains. Mind you, I was throwing on exhaust, intake, and h.f.c.'s all around the same time period, so it's kinda hard to recall each individual change.
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