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Old 01-09-2021, 10:50 PM
Blown353 Blown353 is offline
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If the cam will tolerate it and be smooth at the lower cruise RPM, I might even consider a 3.00 rear gear especially if you do a lot of freeway driving given the .75:1 OD ratio of the 4L80E.

Just make sure the cam will run cleanly at your typical freeway cruising speed in OD with the converter locked, if your cruise RPM is too low for the cam to clean up the resulting engine surge and driveline "chuggle" at your typical freeway speeds is very annoying.

You're going to have traction issues regardless of gear ratio if you don't have right foot discipline. A friend's 70 Chevelle has a 900hp or so F1A procharged 410, 4L80E with an ATI "tight" 2800 stall triple disc converter, 3.42 rear gears, and 305 wide Bridgestone RE-71Rs... WOT is pretty much useless under about 70 on a decent road surface, you have to be smooth and pedal it. If you're going 75-80 in overdrive and stand on it, it will leave stripes after the downshift until you back out of the throttle a bit. Fun? Yes, but you had better be ready for it...
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1969 Chevelle
Old setup: Procharged/intercooled/EFI 353 SBC, TKO, ATS/SPC/Global West suspension, C6 brakes & hydroboost.
In progress: LS2, 3.0 Whipple, T56 Magnum, torque arm & watts link, Wilwood Aero6/4 brakes, Mk60 ABS, Vaporworx, floater 9" rear, etc.
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