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UPDATE! Added second tune option, compliments of RTdes.

S998 Hennessey Venom 800TT

Last week, my area was hit with a bad ice storm that knocked out the power, internet and telephone services.  My wife and I retreated to the in-laws, Xbox in tow.  I began working on this assist-less tune for the Hennessey 800TT for Road America while relegated to offline playing only.  Now that the necessary repairs have been made, I'm throwing this tune out for free.

It is a slightly stiff tune designed to eliminate corner exit understeer.  Most sweepers can been taken in 3rd.  For the sharper turns on Road America, I shift to 2nd for corner entry and shift to 3rd at the apex for optimum corner exit acceleration.  So far, my best time on Road America has been 2:00.7, with my average being around 2:02.  I think that the only improvement left to be made is in the gears.  I have tested the setup on Sunset, Sebring and Road Atlanta as well with great results.  Please post your comments about the tune and your results here, and feel free to propose adjustments.  Enjoy.

Upgrades

All parts stock except as noted below.

Engine
You're kidding, right?

Suspesion/Drive
Race Brakes
Race Springs & Dampers
Race Anti-Roll Bars
Race Transmission
Race Differential

Wheels & Tires
Sport Tires - Pirelli
Upgraded Rim Size (only one option)
RacingHart C4 Rims (RTdes added Motegi rims)

Full Forza Aero Kit (front, back, wing)

Tires                           RTdes Version
Front = 29                   Same Tire Pressures.
Rear = 28                  

Gearing                     
Final Drive = 3.25        Same Gearing.
1st = 2.50
2nd = 1.65
3rd = 1.25
4th = 1.00
5th = 0.86
6th = 0.75

Camber
Front = -0.6                 -1.0
Rear = -0.8                  -0.6

Toe
Front = 0                      0.0
Rear = -0.2                  -.02

Caster = 5.5                5.5

Antiroll Bars
Front = 15.85              10.70
Rear = 17.15               30.25

Springs
Front = 656.4              828.5
Rear = 637.3               840.7

Ride Height (Front and Rear) = 3.4

Rebound Stiffness
Front = 12.0                14.0
Rear = 11.8                 14.5

Bump Stiffness
Front = 10.0                 8.4
Rear = 8.4                    8.9

Aero
Front = 165                  198
Rear = 276                   284

Brakes
Balance = 46% Front
Pressure = Adjust to taste.  I use 105% without ABS.

Differential
Acceleration = 65%
Deceleration = 55%

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GT=Aenyn1
CST - U.S.A.
UMKC Med School Class of 2012

Nice stuff, was planning on getting one of these off the auction house, will have to try your tuining out, cheers !

No prob, man.  Let me know how it works out.

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GT=Aenyn1
CST - U.S.A.
UMKC Med School Class of 2012

Nice! Easy to get the hang of it...
After 6 laps my best time was a 2:01.6.

I went and swapped the RacingHarts for some Motegi rims to put in a sports clutch.

What I didn't like was, that it's still understeering wildly in faster corners...

So you might give this a try. You have to be easy on the curbs, but I was able to post mid 2.01's constantly from 2nd to 5th lap. And I'm sure with a little more work it goes under 2 minutes.
After 6 laps my best personal time was 2.00,3 though.

Camber
Front = -1.0
Rear = -0.6

Toe
Front = 0
Rear = -0.2

Caster = 5.5

Antiroll Bars
Front = 10.70
Rear = 30.25

Springs
Front = 828.5
Rear = 840.7

Rebound Stiffness
Front = 14.0
Rear = 14.5

Bump Stiffness
Front = 8.4
Rear = 8.9

Aero
Front = 198
Rear = 284

:-)

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My Gallery

GT: RTdes

The Food Chain 2008.

Nice pics!  The understeering issue got worse the more I tweaked the transmission.  The default final drive ratio was way to short for the Hennessey's power.  In the default settings the top speed was around 180mph, and the rev limiter was bouncing wildly in protest.  2nd and 3rd gears needed lengthening in order to keep from spinning out in the corners, which caused the understeering issue. 

I'll definately try your tune and see what I get.  Thanks for posting.

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GT=Aenyn1
CST - U.S.A.
UMKC Med School Class of 2012

The Hennessey is U class, correct? (sorry, havn't touched it in a while)

I never did think of tuning the Hennessey for purposes other than going 200mph down short straights.

The stock Hennessey is a little under PI900, I believe.  The Hennessey is very capable on tracks such as Sunset, Road Atlanta, Road America and Sebring as the Forza aero kits and some differential/transmission wizardry help. 

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GT=Aenyn1
CST - U.S.A.
UMKC Med School Class of 2012

Thx for the tune. I finally willed myself to stop running the Endurance races to get $$ and went and won this car, so i'll give your tune a shot.

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GT - V12 Iridium

No prob, man.  Hope it works for you. 

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GT=Aenyn1
CST - U.S.A.
UMKC Med School Class of 2012

Nice one. Thanks for that

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Gamertag - Prince James II
---------------------------------------------------------
My Xbox 360 has E-74 :(

 Great tune and thank you both for the freebie. I have a question for Aenyn how did you paint the white area around the license plate? I can't do it?

I was wondering when somebody was going to point that out...I painted it in photoshop.

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GT=Aenyn1
CST - U.S.A.
UMKC Med School Class of 2012

I took your tune out for a spin, and it's really good.  Might start using the Hennessey Viper more often in some career races (S-Class Endurance, hmm)

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GT - V12 Iridium

Glad to hear it. 

I think my next release will be a good tune for an S Class McLaren F1.

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GT=Aenyn1
CST - U.S.A.
UMKC Med School Class of 2012

"I think my next release will be a good tune for an S Class McLaren F1."

I would definately most appreciate that one.  I recently bought a McLaren and I'm pretty disappointed with the way it handles.

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TGM Racing
GT: CNU PhYsIcS

It is one of the cars I may be entering into the 2008 New Year's tuning challenge.  If I enter it, the tune will not appear on this thread for another week or so.  If I decide to enter another car, I'll have it on this thread by Friday.

-Aenyn

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GT=Aenyn1
CST - U.S.A.
UMKC Med School Class of 2012

nice tune i tried it

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Aenyn:

Bump Stiffness
Front = 10.0                 8.4
Rear = 8.4                    8.9

Brakes
Balance = 46% Front
Pressure = Adjust to taste.  I use 105% without ABS.

Differential
Acceleration = 65%
Deceleration = 55%

I haven't tried this setup (I will), but I have some questions:
Why is bumping stiffnes so astronomously high? I mean: with stiff springs and so stiff bumpers, aren't you going to be sky-rocketed on any surface bump? I never go beyond 4.0 on any RWD car... Well.. I'll check.

As for brakes: rear brake bias? _rear_? Why? It can lock rear wheels... when you only slightly touch the throttle, the turbo is going to spin you into a concrete wall... Next thing to check ;-)

Differential: this is probably why you say it understeers. I know, this car has power, but with such setup, wheels are going to be locked almost all the time. Even worse, when you deaccelerate completly, car has tendency to extreme understeer, because of high braking strenght of the engine.
On the other hand, it might actually benefit this beast because such ridgid LSD might help alot to keep it going straight...

I'll check your tune, just went curious....

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This boy's got talent!

fastviper_PL:

I haven't tried this setup (I will), but I have some questions:
Why is bumping stiffnes so astronomously high? I mean: with stiff springs and so stiff bumpers, aren't you going to be sky-rocketed on any surface bump? I never go beyond 4.0 on any RWD car... Well.. I'll check.

As for brakes: rear brake bias? _rear_? Why? It can lock rear wheels... when you only slightly touch the throttle, the turbo is going to spin you into a concrete wall... Next thing to check ;-)

Differential: this is probably why you say it understeers. I know, this car has power, but with such setup, wheels are going to be locked almost all the time. Even worse, when you deaccelerate completly, car has tendency to extreme understeer, because of high braking strenght of the engine.
On the other hand, it might actually benefit this beast because such ridgid LSD might help alot to keep it going straight...

I'll check your tune, just went curious....

Bump stiffness is high to improve steering response by keeping the tires on the road.  I haven't had any problem with bumps except for the final turn on Sebring. 

The brake bias is a matter of preference.  It helps my turn in response by ensuring keeping the decrease in momentum off the front tires.  Between my braking setup and the diff, I don't have a problem locking the tires.  This is also due to lots of practice.  It's not an easy to drive this car without assists, but very rewarding when done so. 

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GT=Aenyn1
CST - U.S.A.
UMKC Med School Class of 2012

Aenyn:

Bump stiffness is high to improve steering response by keeping the tires on the road.  I haven't had any problem with bumps except for the final turn on Sebring.

That's what springs are supposed to do. When added stiff spring rate cumulates with a bumper that doesn't allow wheel travel up (bump stiffnes), this might lead to simply braking traction.
You might (pardon if you don't) doing the same mistake as I did, and that is considering bound stiffnes to be what in fact _rebound_ stiffness is. And rebound stiffness is what makes a wheel go _back_ to the road quickly after it went up on some bump.
This indeed is a metter of choice, but - do try bump stiffness in range of 1.5-3.0.

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This boy's got talent!