AC GTE @ Road Atlanta - Sunday 15th January 2023

[The Almighty Snark]

Weirdly back in the day I remember no-one took the porker. Maybe 1 or 2 guys.

People just love that RSR! Alas, the normal 911 isn't getting this kind of love

 

[dbx71]

I can match the 911, just! but I am always locking up with the 458 into most corners here.
So the speed is always bleeding away. the 911 is much more front brake forgiving, why, I do not know.

hmmm. ok, thanks for heads up... let's see what i've got myself into! i was driving around the track this morning in the 458 and it felt pretty sweet. i didn't notice locking brakes to be an issue.
however, i'll probably come to discover that it feels relatively easy to control for me because i'm lapping 10 seconds slower than everyone else!

 

[The Almighty Snark]

Pick something that feels comfortable and manageable for an hour! If you can do consistent laps you already a good chance getting a few spots during the race!

 

[Fiberoptix]

Switcheroo is done. Bavaria weeps!

Weirdly back in the day I remember no-one took the porker. Maybe 1 or 2 guys.

I will change to the Ferrari please Brian, for the same sentiment. Struggling to get the gearing right for it on this track but for me its a bit quicker than the 911.

 

[Kek700]

maybe they thought it was just a hyped-up gt3 911.

 

[Kek700]

I will change to the Ferrari please Brian, for the same sentiment. Struggling to get the gearing right for it on this track but for me its a bit quicker than the 911.

Yes know what you mean, you probably know anyway, but here goes.
longest straight, the rev lights on the dash should just all blink as you hit the brakes.
I think it was set for me at about 185mph, not sure. I did not bother with it anymore, without ABS for me it was a no-go.
I love this car, probably my favourite, brilliant, but crap without abs for me. ( moan over )
Then work back wards in 20mph increments till you get to first.

 

[Interslice]

maybe they thought it was just a hyped-up gt3 911.

Possibly put the fear in lads alright! Between that and the big BOP numbers. I was surprised at how forgiving it was when we raced at Fuji.

 

[dbx71]

Yes know what you mean, you probably know anyway, but here goes.
longest straight, the rev lights on the dash should just all blink as you hit the brakes.
I think it was set for me at about 185mph, not sure. I did not bother with it anymore, without ABS for me it was a no-go.
I love this car, probably my favourite, brilliant, but crap without abs for me. ( moan over )
Then work back wards in 20mph increments till you get to first.

for the 458: i dropped the final gear ratio down one click, since i wasnt getting topped out in 6th by the end of final straight... seemed to help, but still not hitting the top of rev range by end of the straight...

 

[Programmer_Rich]

911 please Brian

 

[RasmusP]

for the 458: i dropped the final gear ratio down one click, since i wasnt getting topped out in 6th by the end of final straight... seemed to help, but still not hitting the top of rev range by end of the straight...

You need to take slipstreaming during the race into account too though! Mostly not an issue but if you really get just before the limiter when alone on track, you won't be able to overtake.
Happened to me once and wasn't fun to get "stuck" although getting almost side my side

 

[gearwhine]

A little bit of margin in top gear doesn't hurt plus we sometimes forget power is tailing off at high revs and is probably just as fast in a taller gear

 

[RasmusP]

A little bit of margin in top gear doesn't hurt plus we sometimes forget power is tailing off at high revs and is probably just as fast in a taller gear

Indeed. Although not really the case for the Ferrari

Optimum shifting point would probably be right at the limiter or whatever brings you back to slightly above 6k rpm in the next gear.

 

[gearwhine]

I think our instinct is to always push to the rev limiter or when the revs hit a wall but i do sometimes wonder if i would be faster short shifting a bit.

 

[RasmusP]

I think our instinct is to always push to the rev limiter or when the revs hit a wall but i do sometimes wonder if i would be faster short shifting a bit.

@Neilski can provide a better explanation, but the calculation for the optimum shifting point can be quite complex!
Afaik you would need to draw the power graph, then get the gearing ratio, with the difference in RPM between the gears means how wide your "marked in part of the graph" would be and then find the points where the power in the next gear is identical to the power at the shifting point.
Shift earlier and you'll have less power after shifting. Shift later and you'll end up wasting potentially more power in the next gear

Like this: (Audi TT cup, definitely don't run this into the limiter!)

Or do you need to maximize the integral, Neil?

And then there's the BMW M3 E30, which you definitely want to push right into the limiter:

 

[dbx71]

Pick something that feels comfortable and manageable for an hour! If you can do consistent laps you already a good chance getting a few spots during the race!

good advice right there.

 

[Fiberoptix]

Yes know what you mean, you probably know anyway, but here goes.
longest straight, the rev lights on the dash should just all blink as you hit the brakes.
I think it was set for me at about 185mph, not sure. I did not bother with it anymore, without ABS for me it was a no-go.
I love this car, probably my favourite, brilliant, but crap without abs for me. ( moan over )
Then work back wards in 20mph increments till you get to first.

Thanks Ernie. I am way off that top speed at the end of the straight though, probably about 20mph shy of that currently. Tried various gearing and not sure I can get any more speed out of the sharp right hander before it. Do you change up when the lights blink in the 458? I am holding it in gear longer and maybe need to shift earlier/running too much wing. I've been on practice a couple of times but there were no other drivers. If anybody would be kind enough to share a reference lap with me I would appreciate it.

 

[Fiberoptix]

Indeed. Although not really the case for the Ferrari
View attachment 630833

Optimum shifting point would probably be right at the limiter or whatever brings you back to slightly above 6k rpm in the next gear.

I definitely need to change gear earlier then based on reading this, thanks

 

[Kek700]

My take, for the 458 is that you change when or just before the Rev lights start to flash. It sounds so much better to hear that loverly Ferrari engine Rev and Rev, you will pay a price for that in lost lap time.
I have spent a lot of time with this car, mainly online races, invariably with ABS applied, it is a great car to drive, have I mentioned about needing ABS before..

With ABS I can almost match the Porsche, with out it I am 2 seconds off pace and very random in lap times.

i have front wing 3 rear wing 4 this is to try and get the front to bite better for some of the fast corners, or you will be understeering in downforce corners.
Or if you do not have the balance at the rear, making it unstable.
I still think 4, 5 will be faster with the right driver, just not me.

My top gear is 183 and the diff is 9/35. but I needed to refine that, but there was no point for me, no ABS, have I said that before?
All the rest of the gears are 20mph increments, noting that you can make the gear ratios wider the lower you go. I always try for 20mph increments in 4th and 5th to 6th to maximise high-speed acceleration.
As Rasmus pointed out, it is a lot more complicated, but do I really want to get that involved for one race.

 

[JamKart22]

At the risk of completely filling your screen with apps I've found sidekick very useful in finding the optimum gear change point. From the app...

Q: How do the new optimal shift point rpm lights work?
A: The app pulls data from the file used to draw the power/torque graph in the launcher and uses it to automatically figure out the optimal shift point for each car. On many cars, you won't notice any difference since the engines' maximum power output is very high in the rpm range. But, some cars like SF15-T, Ferrari 458 GT2 and Ferrari 488 GT3 (and many more) reach maximum power on rpms way before the engine hits the limiter. On these cars, there's a learning algorithm that triggers the first time you drive them, where the app learns the gear ratios in order to deduce optimal shift points per gear. Before all of this, the only way to know when to shift correctly on these cars was to look at their dash or steering wheel rpm lights, which can be very inconvenient due to camera choice, FOV, PP filter, steering wheel visibility settings and so on... Now, the app will detect optimal shift points and trigger the rpm lights automatically, per car, without the need to adjust anything. Also, the app detects if the optimal shift point is beyond the limiter and reverts to old behaviour in that case. If for some crazy reason you don't want any of this awesomeness, you can turn it off from the settings sub-app and also adjust the trigger tolerances (although I don't recommend this either).

 

[JamKart22]

At the risk of completely filling your screen with apps I've found sidekick very useful in finding the optimum gear change point. From the app...

Q: How do the new optimal shift point rpm lights work?
A: The app pulls data from the file used to draw the power/torque graph in the launcher and uses it to automatically figure out the optimal shift point for each car. On many cars, you won't notice any difference since the engines' maximum power output is very high in the rpm range. But, some cars like SF15-T, Ferrari 458 GT2 and Ferrari 488 GT3 (and many more) reach maximum power on rpms way before the engine hits the limiter. On these cars, there's a learning algorithm that triggers the first time you drive them, where the app learns the gear ratios in order to deduce optimal shift points per gear. Before all of this, the only way to know when to shift correctly on these cars was to look at their dash or steering wheel rpm lights, which can be very inconvenient due to camera choice, FOV, PP filter, steering wheel visibility settings and so on... Now, the app will detect optimal shift points and trigger the rpm lights automatically, per car, without the need to adjust anything. Also, the app detects if the optimal shift point is beyond the limiter and reverts to old behaviour in that case. If for some crazy reason you don't want any of this awesomeness, you can turn it off from the settings sub-app and also adjust the trigger tolerances (although I don't recommend this either).

It's very useful on the 911 because I hide the wheel (I've got my own ) and the rev lights are on the wheel