You'd have to have a pretty narrow powerband (i.e. my truck's 350, lol) to get out of the powerband in the quarter, even on 4.11's. Figuring a decently built 327 should rev to 5000, 5500 no problem...I know a lot of 4th generation F-Body guys like 4.11's in their 6-speed cars (the 5th and 6th speed overdrives keep the gas mileage up) and they've got up to about 5800RPM to play with, I believe that with 4.11's they're decently deep into 4th in the traps, but they're also making more power. With the 3.42's (like ours has) they're redline in 3rd through the traps.
I think you'd have to go to 4.56 before a lot of motors start having trouble with most trannies and running out of power.
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