top speed per gear question?
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From: Greece
top speed per gear question?
i saw older posts regarding top speed per gear and i compared to mine but numbers on the cluster dont match. For example some AP1's second gear seems to top(flashing red) at 66-67mph but mine and other AP1's seems to top at 60-62mph. any inputs?
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From: Plattsburgh, NY
Last edited by NNY S2k; May 2, 2020 at 05:13 PM.
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From: Greece
I thought of that i have 245/35-18 but its very close to 245/40-17 and 225/50-16. The cluster seems to have a delay that makes it difficult to see but most videos i found AP1's top at 60-61mph or 97kph on the cluster when starts blinking. 65-66 shows when you shift into 3rd so maybe its the delay. was wondering If anyone has seen 65mph+ on second gear before he shifts.
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From: Chesterfield VA
I've been unable to find any documentation on the tachometer flashing near the fuel cutoff point (AKA rev limiter) -- although it does. 
Scanning the manuals doesn't even mention the flashing that I could find.
In OE-tuned engines fuel cutoff occurs at 9000rpm in AP1 and 8200 in AP2 engines (my tuned DBW car has fuel cutoff at 8400rpm) but fuel cutoff is higher than when the tach starts to flash. Dynometer charts I've seen also show peak power a few hundred rpm below fuel cutoff so perhaps the flash is a "shift" indicator before the rev limiter. Rpms on my tuned '06 with VTEC at 3600rpm climb so fast in the lower gears at WOT I really don't have time to watch the tach so I installed a "red line alarm" that beeps at regular increments below the cutoff point. In higher gears it's beep.......beep.......beep..... etc. In first and second it's like an old alarm clock! Yeah, the tack is flashing then too but I prefer eyes outside the car than focusing on the panel.
With my rev limiter set to 8400rpm the math shows my AP2-engined car with CR-spec 255mm rear tires will just brush 60mph in 2d gear. 59.21mph.
None of our cars will hit the theoretical top speeds shown on the linked chart due to aerodynamics (drag coefficient) and insufficient power to overcome it. Drag increases exponentially with speed, hence the enormous amounts of power needed to reach very high speeds.
-- Chuck
Scanning the manuals doesn't even mention the flashing that I could find.In OE-tuned engines fuel cutoff occurs at 9000rpm in AP1 and 8200 in AP2 engines (my tuned DBW car has fuel cutoff at 8400rpm) but fuel cutoff is higher than when the tach starts to flash. Dynometer charts I've seen also show peak power a few hundred rpm below fuel cutoff so perhaps the flash is a "shift" indicator before the rev limiter. Rpms on my tuned '06 with VTEC at 3600rpm climb so fast in the lower gears at WOT I really don't have time to watch the tach so I installed a "red line alarm" that beeps at regular increments below the cutoff point. In higher gears it's beep.......beep.......beep..... etc. In first and second it's like an old alarm clock! Yeah, the tack is flashing then too but I prefer eyes outside the car than focusing on the panel.
With my rev limiter set to 8400rpm the math shows my AP2-engined car with CR-spec 255mm rear tires will just brush 60mph in 2d gear. 59.21mph.
None of our cars will hit the theoretical top speeds shown on the linked chart due to aerodynamics (drag coefficient) and insufficient power to overcome it. Drag increases exponentially with speed, hence the enormous amounts of power needed to reach very high speeds.
-- Chuck
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