Downshifting Habits?
#16
More than a few engines have been blown over the years from the overrevs on a 5-2 downshift.
Every year at Daytona one or two guys rip teeth off 2nd going into turn one because they are in top gear at start finish, go all the way down to 2nd and go in too hot. Cost one of TRG's customer cars a top 10 finish in 2012 when the tooth wedged between the case and shift rod and they had to change the gearbox at 11am.
Every year at Daytona one or two guys rip teeth off 2nd going into turn one because they are in top gear at start finish, go all the way down to 2nd and go in too hot. Cost one of TRG's customer cars a top 10 finish in 2012 when the tooth wedged between the case and shift rod and they had to change the gearbox at 11am.
#17
Go from 5th to 3rd all the time on a few corners we have. Just need to heel / toe / blip correctly. I would guess that n/a cars might be more temperamental due to higher c/r although more responsive to the blipping?
#18
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OP asked what people were doing. Not commentary, IIRC.
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#21
I typically go though the gears sequentially when down shifting. You are much less likely to misjudge your deceleration rate and timing of the down shift with that method, than you are jumping gears. Further, street transmissions do not like engine braking, the engine doesn't care to much for it either, so use the brakes to slow down the car. That's what they are they are designed to do. Do this by delaying the down shift until the RPMs have dropped significantly and with rev matching so the RPMs don't rise significantly when the next gear is engaged. Doing so properly will also help maintain the cars balance in the braking zone. Practice, practice.
Last edited by CCA; 01-17-2015 at 02:07 PM.
#23
You are a lot more likely to match revs properly if you go one gear at a time, so less risk, less wear and tear. If you are heal-toe'ing in the braking zone and there's enough of a speed difference to move down two gears (or more), I'd say you have plenty o' time to go through the gears.
#24
-Mike
#26
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Since the downshift's primary function is to select the optimal gear to accelerate through and out of the corner, it's more about not doing anything that delays throttle application at the onset of the cornering phase. Pursue a strategy that allows subconscious execution with minimal chance (or opportunity) for error.
#27
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#28
#29
IMHO, the key to performance driving is doing exactly the same thing exactly the same way on every lap. There is no "right" or "wrong", just what works for you.
As a rule of thumb, the less activity, the better. On specific turns where a two or more downshift is required (e.g. 5-3, 4-2), I generally "skip-shift". The trick is the timing in the brake zone. If the revs are properly matched, this should not have any impact on the synchs, and a "double shift" simply distracts you from your primary job, which is braking.
Just a tip, the key to successfully executing a skip shift is hand position on the shifter.
Most novices shift with a "hammer-grip" grabbing the shift **** with a clenched fist. This locks the sensitive twitch muscles in your hand and wrist, and moves the job of locating the shift gate to the relatively crude muscles of the upper arm and shoulder.
Combined with the somewhat bewildering preference of drivers for short shift throws and tight gear gate spacing, this greatly increases the probability of a "money shift".
I recumbent that students shift with an "open palm", positions 180 degrees from the gear gate desired. For example, a shift to 2nd (either up or down) should have pressure at 2 o'clock, and a pull toward your right leg.
A shift to 3rd (up or down) should position the palm at 7 o'clock, and a push toward the glove-box.
Any shift to 4th (up or down) should use a "backhand" position with the palm at 10 o'clock, thumb pointing to the floor, and a pull toward the passenger seat.
Every shift has a totally unique hand position and movement, thus minimizing the possibility of missing the gate.
As a rule of thumb, the less activity, the better. On specific turns where a two or more downshift is required (e.g. 5-3, 4-2), I generally "skip-shift". The trick is the timing in the brake zone. If the revs are properly matched, this should not have any impact on the synchs, and a "double shift" simply distracts you from your primary job, which is braking.
Just a tip, the key to successfully executing a skip shift is hand position on the shifter.
Most novices shift with a "hammer-grip" grabbing the shift **** with a clenched fist. This locks the sensitive twitch muscles in your hand and wrist, and moves the job of locating the shift gate to the relatively crude muscles of the upper arm and shoulder.
Combined with the somewhat bewildering preference of drivers for short shift throws and tight gear gate spacing, this greatly increases the probability of a "money shift".
I recumbent that students shift with an "open palm", positions 180 degrees from the gear gate desired. For example, a shift to 2nd (either up or down) should have pressure at 2 o'clock, and a pull toward your right leg.
A shift to 3rd (up or down) should position the palm at 7 o'clock, and a push toward the glove-box.
Any shift to 4th (up or down) should use a "backhand" position with the palm at 10 o'clock, thumb pointing to the floor, and a pull toward the passenger seat.
Every shift has a totally unique hand position and movement, thus minimizing the possibility of missing the gate.
#30
IMHO, the key to performance driving is doing exactly the same thing exactly the same way on every lap. There is no "right" or "wrong", just what works for you.
As a rule of thumb, the less activity, the better. On specific turns where a two or more downshift is required (e.g. 5-3, 4-2), I generally "skip-shift". The trick is the timing in the brake zone. If the revs are properly matched, this should not have any impact on the synchs, and a "double shift" simply distracts you from your primary job, which is braking.
Just a tip, the key to successfully executing a skip shift is hand position on the shifter.
Most novices shift with a "hammer-grip" grabbing the shift **** with a clenched fist. This locks the sensitive twitch muscles in your hand and wrist, and moves the job of locating the shift gate to the relatively crude muscles of the upper arm and shoulder.
Combined with the somewhat bewildering preference of drivers for short shift throws and tight gear gate spacing, this greatly increases the probability of a "money shift".
I recumbent that students shift with an "open palm", positions 180 degrees from the gear gate desired. For example, a shift to 2nd (either up or down) should have pressure at 2 o'clock, and a pull toward your right leg.
A shift to 3rd (up or down) should position the palm at 7 o'clock, and a push toward the glove-box.
Any shift to 4th (up or down) should use a "backhand" position with the palm at 10 o'clock, thumb pointing to the floor, and a pull toward the passenger seat.
Every shift has a totally unique hand position and movement, thus minimizing the possibility of missing the gate.
As a rule of thumb, the less activity, the better. On specific turns where a two or more downshift is required (e.g. 5-3, 4-2), I generally "skip-shift". The trick is the timing in the brake zone. If the revs are properly matched, this should not have any impact on the synchs, and a "double shift" simply distracts you from your primary job, which is braking.
Just a tip, the key to successfully executing a skip shift is hand position on the shifter.
Most novices shift with a "hammer-grip" grabbing the shift **** with a clenched fist. This locks the sensitive twitch muscles in your hand and wrist, and moves the job of locating the shift gate to the relatively crude muscles of the upper arm and shoulder.
Combined with the somewhat bewildering preference of drivers for short shift throws and tight gear gate spacing, this greatly increases the probability of a "money shift".
I recumbent that students shift with an "open palm", positions 180 degrees from the gear gate desired. For example, a shift to 2nd (either up or down) should have pressure at 2 o'clock, and a pull toward your right leg.
A shift to 3rd (up or down) should position the palm at 7 o'clock, and a push toward the glove-box.
Any shift to 4th (up or down) should use a "backhand" position with the palm at 10 o'clock, thumb pointing to the floor, and a pull toward the passenger seat.
Every shift has a totally unique hand position and movement, thus minimizing the possibility of missing the gate.