I figure my stock tach is around 200 rpm fast. I was shifting around 6000 with tach and no real problems. I put a shift light in with 6000 pill, and if I don't shift, like right at the light the rev limiter hits (especially in 1st when the revs are climbing fast). Now I learn that the rev limiter is 6250 so I think I was really shifting at around 5800.
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'92 GT conv.
TFS heads, GT40, Powerdyne 9#, AOD, 3.73
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