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Discussion Starter · #1 ·
I finally had the chance to take my 2008 Audi R8 V8 to the drag strip after 3 years of ownership. I have the gated 6-speed manual, stage 2 tune + custom exhaust and in 3 runs only managed to get a 13.2-second quarter mile. I have the Michelin Pilot 4S tires with 305s in the back and I still seemed to be struggling with traction. Any advice on how to launch the manual cars? I turned off launch control as well and tried dumping the clutch at 3K RPM.



I would expect to be running in the low 12s? I had a passenger as well on the runs.
 

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You won't get low 12's. First you have a passenger in the car. Second you have a manual. Third the tunes don't add much to the naturally aspirated V8's despite marketing claims from the vendors. My guess is that you should be seeing about 12.8 seconds. Stock with a 1-ft rollout, by professionals in the R-tronic the R8 does about 12.6 seconds.
 

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Post your trap speeds. Better indicator of whether car or driver is underperforming.
 

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Disclaimer: I'm not experience at the drag strip but I am experienced with road racing circuits on a lot of different cars.

I think that I can safely assume that torque at launch won't be too critical (mid-engine/flat plane). Looking at V8 dyno sheets (stock), you want to be at just under 4k for access to a nice torque window. (Any drag veterans that want to confirm?)

If you have traction issues then your biggest problem, I'm going to guess, is tire grip. The PS4S is an incredible tire but it's not that great for any kind of track duty. What tire pressures/temps are you running? I'd recommend an RE71R from experience but that tire is discontinued. For street tires, I'd give Supercar 3 or g-Force Rival S a shot based on what teamates have said for use in time attack/time trials. I haven't used either though.

The relevant street tires that I have track experience with and don't recommend are Cup 2s and Trofeos. They're faster tires but not because of launch grip.

STAY AWAY FROM TOYO R888/R - THIS THE MOST OVER RECOMMENDED AND OVER RATED TIRE EVER. If you ask 9/10 people on track what they think of them, they'll vomit at the thought and the other 1 person would say he never used them.
 

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Like others said....post the entire time slip.

60', 330', 1/8th ET & MPH, 1000', and 1/4mi ET and MPH

ET is how good the car can hook up
MPH is how much power it's putting down

The V8 R8 is not a straight line car to be honest. Not much oomph compared to what's out there these days. As long as you have fun that's all that matters but I'm not surprised at the times.

EDIT: Just saw the post above about the R888. Can't comment on the R888R but I used the R888 on my GT-R back in the day. Loud tire but it was like glue for hooking on the street. Couldn't complain.
 

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Here's a target for you. Road and Track managed to get a 12.5 quarter mile in a manual, and for manual fans, they managed to do 0.3 seconds faster to 60 and 0.1 seconds faster in the 1/4 mile than the R tronic - it was all about the launch. Check it out:

 

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Road and Track is insane: "The 6-speed manual gearbox, on the other hand, lets you rev the 4.2-liter V-8 all the way to redline (8250 rpm) before dropping the clutch to get the optimal amount of wheelspin while taking off."! Okayyyy.... But if you're aggresive enough CR, there is your answer on how to do a better ET. I think the reality is you are having traction issues at 3K but R&T is doing 8K launches, so your tires are most likely the issue. Car mags test with brand new tires and play around with everything (pressures, temps) to get the lowest possible ET.
 

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Road and Track is insane: "The 6-speed manual gearbox, on the other hand, lets you rev the 4.2-liter V-8 all the way to redline (8250 rpm) before dropping the clutch to get the optimal amount of wheelspin while taking off."! Okayyyy.... But if you're aggresive enough CR, there is your answer on how to do a better ET. I think the reality is you are having traction issues at 3K but R&T is doing 8K launches, so your tires are most likely the issue. Car mags test with brand new tires and play around with everything (pressures, temps) to get the lowest possible ET.
And they're not worried about blowing up the drivetrain in the process......
 

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Discussion Starter · #10 ·
Disclaimer: I'm not experience at the drag strip but I am experienced with road racing circuits on a lot of different cars.

I think that I can safely assume that torque at launch won't be too critical (mid-engine/flat plane). Looking at V8 dyno sheets (stock), you want to be at just under 4k for access to a nice torque window. (Any drag veterans that want to confirm?)

If you have traction issues then your biggest problem, I'm going to guess, is tire grip. The PS4S is an incredible tire but it's not that great for any kind of track duty. What tire pressures/temps are you running? I'd recommend an RE71R from experience but that tire is discontinued. For street tires, I'd give Supercar 3 or g-Force Rival S a shot based on what teamates have said for use in time attack/time trials. I haven't used either though.

The relevant street tires that I have track experience with and don't recommend are Cup 2s and Trofeos. They're faster tires but not because of launch grip.

STAY AWAY FROM TOYO R888/R - THIS THE MOST OVER RECOMMENDED AND OVER RATED TIRE EVER. If you ask 9/10 people on track what they think of them, they'll vomit at the thought and the other 1 person would say he never used them.
Thanks for the insight and the timing of this is hilarious, someone just recommended the R888 to me :D
 

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Discussion Starter · #11 ·
Road and Track is insane: "The 6-speed manual gearbox, on the other hand, lets you rev the 4.2-liter V-8 all the way to redline (8250 rpm) before dropping the clutch to get the optimal amount of wheelspin while taking off."! Okayyyy.... But if you're aggresive enough CR, there is your answer on how to do a better ET. I think the reality is you are having traction issues at 3K but R&T is doing 8K launches, so your tires are most likely the issue. Car mags test with brand new tires and play around with everything (pressures, temps) to get the lowest possible ET.
**** they are crazy, dumping the clutch at that RPM puts fear in my heart!
 

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Thanks for the insight and the timing of this is hilarious, someone just recommended the R888 to me :D
I think it's because the compound difference between typical street tires and the 100 treadwear R888R makes it look better than what it is. Now, to be fair, maybe they're ok for acceleration but for track use they heat cycle very quickly, they get greasy extremely fast, they're not good in wet conditions at all (which is kind of similar to a lot of tires in the range) and their cornering grip is a huge disappointment - the sidewalls are excessively stiff. The Nitto NT01 is the better alternative to it.
 

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**** they are crazy, dumping the clutch at that RPM puts fear in my heart!
Yeah, I've had the pleasure of blowing up a CV joint doing that on a '77 323i I had - granted I had done a bit of engine work and it was actually a 2.7 liter block, but talk about going home with your tail between your legs.
 

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Here is a video my Manual V10 with Stasis Exhaust and Tune running on a perfect cool night Zero Humidity( Cant get the video to work) Ugh
OK so you can see my results here.2011 Audi R8 v10 1/4 mile Drag Racing timeslip specs 0-60 - DragTimes.com
This was a couple of years ago in my old 2011 R8. No issues coming off the line on brand new P4S at 28 lbs air pressure . Leave the line at 5000 rpm slip the clutch for first 30-50 ft and then go full out but short shift to 2nd at about 8400 RPM.Limited wheelspin and I actually ran an 11:39 a few nights later.( The link) I bought a Stronic V10 after I sold that one and ran slower than the manual. Even with launch control I could not match the off the line performance of the manual. Your V8 should run in mid to low 12;s under ideal conditions.
BTW I was racing an Aventador. His times were better but I cut the light way better and beat him to the end.
264408

264407
 

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I finally had the chance to take my 2008 Audi R8 V8 to the drag strip after 3 years of ownership. I have the gated 6-speed manual, stage 2 tune + custom exhaust and in 3 runs only managed to get a 13.2-second quarter mile. I have the Michelin Pilot 4S tires with 305s in the back and I still seemed to be struggling with traction. Any advice on how to launch the manual cars? I turned off launch control as well and tried dumping the clutch at 3K RPM.

I would expect to be running in the low 12s? I had a passenger as well on the runs.
For sure PSC2's (and no passenger) would help some but I can mat the throttle on our 2012 R8 V10 with PS4S's (2 years old) at 39 psi front and 36 psi rear with our Ohlins TTX suspension. (I could not with the mag rides and lost traction often).

What rear tire pressures are you running?

Quattro still?

Are you still on the BC Coilovers? Can you soften the rear compression low speed adjuster for these drag runs? Our customers who switched to ours from BC noted it takes very big adjustment to feel a change on the BC's.
 

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Discussion Starter · #16 ·
For sure PSC2's (and no passenger) would help some but I can mat the throttle on our 2012 R8 V10 with PS4S's (2 years old) at 39 psi front and 36 psi rear with our Ohlins TTX suspension. (I could not with the mag rides and lost traction often).

What rear tire pressures are you running?

Quattro still?

Are you still on the BC Coilovers? Can you soften the rear compression low speed adjuster for these drag runs? Our customers who switched to ours from BC noted it takes very big adjustment to feel a change on the BC's.
I was running 32 PSI all-around tire pressure and yes Quattro. I am still on BC Racing but did a tune and adjustment to stiffen it for the track, instead you are saying I should soften the rear huh? Will that aid with traction to have a softer rear and stiffer front?

Here is the run vs the GTR alone
 

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I was running 32 PSI all-around tire pressure and yes Quattro. I am still on BC Racing but did a tune and adjustment to stiffen it for the track, instead you are saying I should soften the rear huh? Will that aid with traction to have a softer rear and stiffer front?

Here is the run vs the GTR alone
Drag racing - straight line and your primary issue and challenge appears to be power down. The GTR must have missed shifts or something went quite wrong in the middle for them and then got going again because they had a good launch

You want to be as soft on the hit on the rear tires as you can (and fronts also in the quattro case). And drag cars you you see the front end come up a fair amount (soft rear compression and soft front rebound)

Tire Pressures
  • Front - high usually to reduce tire drag, but since you are quattro and can use the grip I think your front pressures are reasonable at 32 psi for a balance of grip and tire drag
  • Rear - Softer for launch - I would go down 2-4 psi for more traction - so 28-30 psi as a start
    • High speed is hard on tires (heat), but this is a short run and not that high of speed
Coilovers
  • Have you swapped the BC spring rates front to rear like many here so you are slightly softer on the spring at the back than the front (I believe the BC's normally came a little more stiff in the rear)?
    • If not, I would swap them for your general running and it will help this straight line running
      • However, this then warrants adjustment of dampers for the spring change, but a few have posted their settings - my apologies if you have done this already

The following is in general and assumes the standard damping is correct for the springs and R8 stiffness and mass
  • Straight Line - Rear Damping - more important than the front
    • Compression - Softer than normal - you want to be easy on the tire - stiffening the compression hits the tire faster and harder - hurts power down
      • Your weight is transferring quickly to the rear on launch
      • This is a balancing act on road courses between grip and body control/response, but not in straight line only
    • Rebound - Your normal road setting to maybe a little softer - to help power down and control on bumps, but you don't want more here either
  • Straight Line Quattro - Front Damping
    • Compression - Normal to a little softer Compression to help on grip/traction but also control the bumps
    • Rebound - Softer for power down of the front tires - the front end is trying to lift as the weight transfers to the rear and you want to allow this to happen otherwise it is trying to bring the front tires up also

Launch - Engine RPM
  • Your launch RPM seems low since peak Torque for your engine it appears is around 4500 RPM plus...correct?
  • You are on stickier drag pavement so for speed it seems you want to launch a little above that if you have good grip/traction
    • Of course the driveline in these cars are designed for about 1 G cornering, braking and accelerating (with some margin) and then a certain amount of shock loading like these launches
      • However, traction compound at a drag strip/a lot of rubber down and a good launch will likely exceed what the car is designed for (clutch, gears, axles, etc) so this not without risk for speed

In the end, the R8 is a incredible car on the road course and not intended for straight line...though the brakes (fluid, rotors and pads) should be upgraded for road course track days.

Have fun!

Scott
 
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