Heavy breaking = good turn in but...
02-06-2014, 02:28 PM
#1
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Heavy breaking = good turn in but...
Right now the way my car is setup I can get it to turn in real nice.
I can transfer the weight to the front with the brakes.
How are you guys getting the weight back on to the rears so
1) it doesn't oversteer in the turn
2) you can get back on the power as soon as possible
I can transfer the weight to the front with the brakes.
How are you guys getting the weight back on to the rears so
1) it doesn't oversteer in the turn
2) you can get back on the power as soon as possible
02-06-2014, 03:26 PM
#4
Pro
Right now the way my car is setup I can get it to turn in real nice.
I can transfer the weight to the front with the brakes.
How are you guys getting the weight back on to the rears so
1) it doesn't oversteer in the turn
2) you can get back on the power as soon as possible
I can transfer the weight to the front with the brakes.
How are you guys getting the weight back on to the rears so
1) it doesn't oversteer in the turn
2) you can get back on the power as soon as possible
Only using the brake to get weight transfer to front wheels , make turn in and then off brake and rolling back into the throttle. Once you start to make the turn you are already starting to unload the front of the car so by getting back on the gas gets the car to start setteling the rear end for the drive off the corner.
02-06-2014, 03:57 PM
#5
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I thought that's what I was doing.
At the end of the season, I was leaving the traction control on until the tires came up to temp
The car stayed on line much better.
Keep in mind I'm running a supercharged 383
The boost comes on about 3,000rpm
and when it does it's rather sudden.
At the end of the season, I was leaving the traction control on until the tires came up to temp
The car stayed on line much better.
Keep in mind I'm running a supercharged 383
The boost comes on about 3,000rpm
and when it does it's rather sudden.
02-06-2014, 04:27 PM
#6
Race Director
I'm assuming C4, right?
The suspension on the C4 is not as "friendly" as the newer cars.. by a loooooong way, and the weight transfer characteristics are a lot different as well. The gentle "rolling off/rolling on" that plants the C5 so well didn't work so well in that car. I found that it takes a lot more brute force to get the weight where you want it than in the C5/C6. Long story short, it took a lot of steering with the gas pedal to get it planted and rotated.
With mine (~500hp N/A 383) it had a LOT of understeer if you were off the throttle and a lot of oversteer if you were on it too hard... but if you got it in the sweet spot, it was a rocket. You could get it to rotate very well with a little bit of throttle, keep it loaded up on the outside rear with a little maintenance throttle and get back on the gas very early with it on exit.
Every car is a "momentum car". We have all heard it, but the C4 is a completely different animal than the C5/C6. I tried all sorts of lines and driving styles over the years in mine. By FAR, the fastest lap times I ever ran were when I sacrificed some mid-corner speed, got it pointed in the right direction as soon as possible and let the big 383 do it's thing.
The suspension on the C4 is not as "friendly" as the newer cars.. by a loooooong way, and the weight transfer characteristics are a lot different as well. The gentle "rolling off/rolling on" that plants the C5 so well didn't work so well in that car. I found that it takes a lot more brute force to get the weight where you want it than in the C5/C6. Long story short, it took a lot of steering with the gas pedal to get it planted and rotated.
With mine (~500hp N/A 383) it had a LOT of understeer if you were off the throttle and a lot of oversteer if you were on it too hard... but if you got it in the sweet spot, it was a rocket. You could get it to rotate very well with a little bit of throttle, keep it loaded up on the outside rear with a little maintenance throttle and get back on the gas very early with it on exit.
Every car is a "momentum car". We have all heard it, but the C4 is a completely different animal than the C5/C6. I tried all sorts of lines and driving styles over the years in mine. By FAR, the fastest lap times I ever ran were when I sacrificed some mid-corner speed, got it pointed in the right direction as soon as possible and let the big 383 do it's thing.
Last edited by RedLS1GTO; 02-06-2014 at 04:31 PM.
02-06-2014, 04:27 PM
#7
Instructor
Right now the way my car is setup I can get it to turn in real nice.
I can transfer the weight to the front with the brakes.
How are you guys getting the weight back on to the rears so
1) it doesn't oversteer in the turn
2) you can get back on the power as soon as possible
I can transfer the weight to the front with the brakes.
How are you guys getting the weight back on to the rears so
1) it doesn't oversteer in the turn
2) you can get back on the power as soon as possible
02-06-2014, 04:40 PM
#8
Race Director
Each driver is going to be different, but from my experience with a somewhat similar car that didn't work at all. With a big front weight distribution (especially with a spuercharged 383) The C4 needs help rotating the rear, not planting the nose.
Again, each car and driver style is different, but at least from the experience of mine, the issue isn't that there isn't enough weight forward... it's that there is TOO MUCH weight forward.
Again, each car and driver style is different, but at least from the experience of mine, the issue isn't that there isn't enough weight forward... it's that there is TOO MUCH weight forward.
02-06-2014, 10:29 PM
#10
Pro
My 0.02
If you feel like you still need TC in any scenario, you likely are not getting enough "feel" from the car. A racing seat (very little padding) will likely be a big help. If you already have that, then seat time. Trial and error is the best way for most of us understand when to back off the brake and when to hit the gas. Develop a plan for varying your approach. Every couple laps change it up and record your results.
If you feel like you still need TC in any scenario, you likely are not getting enough "feel" from the car. A racing seat (very little padding) will likely be a big help. If you already have that, then seat time. Trial and error is the best way for most of us understand when to back off the brake and when to hit the gas. Develop a plan for varying your approach. Every couple laps change it up and record your results.
02-07-2014, 09:19 AM
#13
I second the race seat. Brian your stock seats had me sliding all over. Your car is hard to tell when the suspension is loaded from my experience driving it. That C4 seems way stiffer than my car and Bills Z06.
02-07-2014, 02:20 PM
#14
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Ok, back history needed.
The suspension is no longer stock, back when it was it behaved exactly as everyone is describing.
and this is autocross, I haven't been back to the track since the rebuild.
The car has coilovers on it.
The dual rates I had in before just were not working out so I replaced them with single rate coils equivalent to a Z07 suspension.
I have adjustable a-arms on the front, so I was able to crank my front camber and caster up
-2.5 camber front
-2.0 camber rear
which on a C4 is a lot.
The rear suspension is all rod end now.
I'm also running DRM plates in the back.
The swaybars are 30mm front 26mm rear (Z07 size)
Of course I'm running 335 Hoosiers on all 4.
The suspension is no longer stock, back when it was it behaved exactly as everyone is describing.
and this is autocross, I haven't been back to the track since the rebuild.
The car has coilovers on it.
The dual rates I had in before just were not working out so I replaced them with single rate coils equivalent to a Z07 suspension.
I have adjustable a-arms on the front, so I was able to crank my front camber and caster up
-2.5 camber front
-2.0 camber rear
which on a C4 is a lot.
The rear suspension is all rod end now.
I'm also running DRM plates in the back.
The swaybars are 30mm front 26mm rear (Z07 size)
Of course I'm running 335 Hoosiers on all 4.
02-07-2014, 04:48 PM
#19
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I have data from one of my runs vs other C4 Corvettes that were there the same day.
so here we go
The other C4's put in very similar time despite very different lines.
I notice one slowed WAY down before entering a turn then more than made up for it.
so here we go
The other C4's put in very similar time despite very different lines.
I notice one slowed WAY down before entering a turn then more than made up for it.