Speedshift and Cornering Question
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Member
Joined: Dec 2003
Posts: 219
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From: San Diego, CA
2006 Corvette Coupe
Speedshift and Cornering Question
Isn't speedshift suppose to hold a gear when corning forces exceed 0.5 G? I'm pretty sure today,when I drove Summit with the transmission in "D," that there were kick downs while accelerating out of the apex, and that these happened during hard lateral acceleration.
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Joined: Nov 2002
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From: Boston/Hartford
cschow,
Yes that is what I thought speedshift was supposed to do too but it does not. You have to be careful with the throttle when apexing a turn or else it shifts down and it messes you up.
Here are two different methods that I have tried and it works pretty well.
Method 1
Put Car in D
Enter turn and turn in then get on the pedal very carefully do not exceed the halfway point or else it kicksdown. you can do this on tighter curves and it works pretty good. Then floor it right as you are about 3/4 of the way out of the curve. It will kick down and give you good speed exiting the curve.
Method 2 - What I do.
When I start braking for the turn I hold the lever all the way to the left until I am just finishing braking or start trail braking. This is usually the right gear for the corner as speedshift does a fairly good job of selecting the gear under heavy braking.
Then I just leave this gear for ther corner and you can get on the throttle a little bit more but still not all the way as you don't really want to do that at the apex anyways. Then at approximately 3/4 or at the end of turn you will run out of reves and speedshift will automatically shift up.
Rinse and repeat for the next curve.
I would be interested to hear how some of the more experienced track people cope with the automatic in this car. I have had many instructors complain about speedshift in slower turns. It seems to be fine in faster ones though.
Prasith
Yes that is what I thought speedshift was supposed to do too but it does not. You have to be careful with the throttle when apexing a turn or else it shifts down and it messes you up.
Here are two different methods that I have tried and it works pretty well.
Method 1
Put Car in D
Enter turn and turn in then get on the pedal very carefully do not exceed the halfway point or else it kicksdown. you can do this on tighter curves and it works pretty good. Then floor it right as you are about 3/4 of the way out of the curve. It will kick down and give you good speed exiting the curve.
Method 2 - What I do.
When I start braking for the turn I hold the lever all the way to the left until I am just finishing braking or start trail braking. This is usually the right gear for the corner as speedshift does a fairly good job of selecting the gear under heavy braking.
Then I just leave this gear for ther corner and you can get on the throttle a little bit more but still not all the way as you don't really want to do that at the apex anyways. Then at approximately 3/4 or at the end of turn you will run out of reves and speedshift will automatically shift up.
Rinse and repeat for the next curve.
I would be interested to hear how some of the more experienced track people cope with the automatic in this car. I have had many instructors complain about speedshift in slower turns. It seems to be fine in faster ones though.
Prasith
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Joined: Dec 2001
Posts: 290
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From: Ashland, Ohio
ex-C32
The engine will only hold RPMs until your right up on the rev limiter as I was on Mid-Ohio turns 10-11. The timing gets pulled way back and the shift made. It will not down shift while braking and turning into a turn but will up shift if the g-load or steering angle is not too great.
You should be able to pull the shifter to the left right before turn in on turn 1, 6a and b and the front straight for 2nd gear exit.
Have fun and keep the shiny side up!
Norm
Bordeu/Merlot
P.S. Tell dsC32 in the silver C32 with KS plates I said hello!
You should be able to pull the shifter to the left right before turn in on turn 1, 6a and b and the front straight for 2nd gear exit.
Have fun and keep the shiny side up!
Norm
Bordeu/Merlot
P.S. Tell dsC32 in the silver C32 with KS plates I said hello!
Member
Joined: Jul 2004
Posts: 113
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From: GTA
my tranny holds pretty good today in D... i just come back from track...so tired.
took some video versus M3... but both of us got kicked@$$ by Hondas...
i got 45psi in my front stock tyres, it understeer crazy... i went straight to the grass on the mainstraight back... great that no damage have been done phew it was a very high speed turn... great that i can recover it without spining around...
hope i can put the videos on asap...
took some video versus M3... but both of us got kicked@$$ by Hondas...
i got 45psi in my front stock tyres, it understeer crazy... i went straight to the grass on the mainstraight back... great that no damage have been done phew it was a very high speed turn... great that i can recover it without spining around...
hope i can put the videos on asap...
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Posts: 318
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From: Boston, MA
2004 C32 AMG
Originally Posted by derAMG
i got 45psi in my front stock tyres
Keep in mind, when you drive, your tires heat up causing an increase of pressure. Under hard driving, I'm sure your tires are running above 45psi. I wouldn't go anywhere close to that! Isn't the max psi 44?
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Joined: Jul 2004
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From: GTA
Originally Posted by hantzis
45psi
Keep in mind, when you drive, your tires heat up causing an increase of pressure. Under hard driving, I'm sure your tires are running above 45psi. I wouldn't go anywhere close to that! Isn't the max psi 44?
Keep in mind, when you drive, your tires heat up causing an increase of pressure. Under hard driving, I'm sure your tires are running above 45psi. I wouldn't go anywhere close to that! Isn't the max psi 44?
Super Member
Joined: Dec 2003
Posts: 815
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43-48 hot is where you want most street tires to be. Toyo's racing division that offeres track side support for the T1-S's recommends a hot temp of 45psi for optimum performance. Of course, results may vary as do driver preferrence and the vehicle in which you run.
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From: GTA
Originally Posted by smgC32
43-48 hot is where you want most street tires to be. Toyo's racing division that offeres track side support for the T1-S's recommends a hot temp of 45psi for optimum performance. Of course, results may vary as do driver preferrence and the vehicle in which you run.
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Joined: Dec 2003
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These are hot temps, not cold. If you are running an autocross or a single short lapping session, start with higher cold temps. These short sessions don't have enough time to bring the tires up to temperatures. If you are running a whole day of sessions, start with a lower temp, but the first session will not feel as good. I start out with a higher cold temp to be in "the zone" faster, then bleed off hot air to my preferred operating temps.
