AWD 1st gear exit speed on 1/4 indy

[ampire]

I've been working on tuning a LM Quattro. Fully broken in at 910 horsepower (high miler).

Track is Indy.

I've noticed traction is not a problem when 1st gear ends. Currently geared so 1st gear ends at about 40 mph (actually redlines at 51 mph when not doing a dead start) . Shifting to enter each subsequent gear at 6000, peak power is at 6600 rpm, and 4th gear tops out at about 154 mph.

Do you guys prefer lower or higher speeds when exiting 1st?

Lower speed you regain traction sooner but lose on the pull to an opponent with better traction.

 

[DLR]

Each car has a balance which you need to find. My Le Mans traps 158mph and I know it can do more. Keep tweaking until you find the sweet spot.

 

[deltadave59]

I launch mine in 2nd and it never spins,pulls hard too.i think it traps at about 156-157

 

[ampire]

Okay I will work at doing a 2nd gear launch. Maybe thats been the missing link here. I've been trying 1st gear launches for the longest time and tweaking it with a variety of setups. I use fully locked front and rear diff. No ballast. Torque split 45/55.

I am using a rwd style suspension, low front high back, shocks stiff expansion in back and loose in front, compression loose in back and tight in front, loose front spring tight rear spring...

 

[DLR]

For Le Mans you could launch in either 1st or 2nd. IMO 1st is better.


BTW I got my Le Mans up to 159 now!! (Thanks to ptk tuning system )

 

[Mikeybc]

For Le Mans you could launch in either 1st or 2nd. IMO 1st is better.


BTW I got my Le Mans up to 159 now!! (Thanks to ptk tuning system )

Is your trap speed at the shadow or at the full 1/4 mile a few posts beyond? I thought my 155-156 at the shadow was decent until I finally found some fast people to race. If your speed is at the shadow I have a lot of work to do.

 

[DLR]

Is your trap speed at the shadow or at the full 1/4 mile a few posts beyond? I thought my 155-156 at the shadow was decent until I finally found some fast people to race. If your speed is at the shadow I have a lot of work to do.

Well I race at the true 1/4 mile. At the shadow, I'm assuming around 156-157 ish.

 

[Mikeybc]

Well I race at the true 1/4 mile. At the shadow, I'm assuming around 156-157 ish.

Thanks for clarifying that, when I do manage to get to race online I rarely see anyone using a Le Mans Quattro and its hard to judge how a tune really is or how its progressing.

 

[AKA I95]

mine does 154 mines slow

 

[ampire]

I got it up to doing about 155 by the shadow using 2nd gear launch and better gearing. Based on my tests, suspension doesn't make a difference on this car as much as on others.

 

[eightlives]

Well I race at the true 1/4 mile. At the shadow, I'm assuming around 156-157 ish.

so you race at Fuji then? 💡

I know you are not claiming Indy at 370meters is the "true" 1/4mile.

 

[DLR]

so you race at Fuji then? 💡

I know you are not claiming Indy at 370meters is the "true" 1/4mile.

Fuji is too long. I race to a few cars after the shadow at Indy. Measured with C4. EXACTLY 1/4 mile

 

[eightlives]

Fuji is too long. I race to a few cars after the shadow at Indy. Measured with C4. EXACTLY 1/4 mile

Indy from in front of the yellow to the shadow is 370meters
Indy from in front of the yellow to half way between the shadow and the end of the concert is 400meters, but impossible to tell a winner

Fuji from in front of the shadow before finish line, to shadow after finish line is 407meters.

I would rather run 7meters too much, than 30meters to little.

 

[Mikeybc]

Why not park one of those big white boxes on the grass right next to the track 400 meters (plus a car length) from the yellow paint, that will give good visual reference of a true quarter mile at Indy

 

[DLR]

Why not park one of those big white boxes on the grass right next to the track 400 meters (plus a car length) from the yellow paint, that will give good visual reference of a true quarter mile at Indy

 

[savage388]

Why not park one of those big white boxes on the grass right next to the track 400 meters (plus a car length) from the yellow paint, that will give good visual reference of a true quarter mile at Indy

That's a great idea, how come no one has ever thought of it ?