FUTCC Audi S4 V8

[Robs]

Hey all,

This tuesday night i will begin my online racing career in the Forza UK Touring car Championship. Cheers to Ske to pointing me at it, i managed to sneak in and grab the last drivers position and find myself needing a car and a tune ready for this Tuesday night for full length Mugello!

I intend to use this thread to chart how the season goes for me, how the car develops and hopefully for you guys to throw me some advice to a novice tuner/racer.

First the Artwork, this is the car so far - any ideas or thoughts to make it better for tuesday greatly appreciated:




The Build:-

Regulation Avon Racing Slicks, max width on 20" Volk GT-C's.
Front and rear Forza bumpers, and forza rear Wing
All Race platform apart from Weight Reduction, which is sport (final weight = 2825lbs)
Race Intake, Exhaust and Street Fuel system takes it to A850 with 391bhp/347lb-ft torque.

Now the tune im using so far is a take on a fuerdog starting point and goes like this:-

Tyres:- F 29 - R 28
Gears:- Final Drive 3.20
Camber:- F -0.8 R -0.8
Toe:- F 0.1 R 0.1
Caster:- 5.5
ARB's:- F 18.51 R 16.47
Springs:- F 406.8 lb/in R 497.4 lb/in
Height:- F 4.3in R 4.3in
Rebound Stifness:- F 11.0 R 9.2
Bump Stifness:- F 7.3 R 8.4
Aero:- F 80lbs R 90lbs
Braking:- 47% Front, 90% Pressure
Diffs:- F 40% Accell/0% Decell - R 65% Accell/65% Decell
Center Torque:- 40%/60%

What are peoples initial thoughts? I know that Ske and others are doing 1:51/1:52's on Mugello where as my best so far is a 1:55.4 so i know i have to speed up. I feel my top end is too slow, could not keep up with my brothers Bora or Astra down the main straight, but was quicker through the bends.

Any help will be greatly appreciated,

Cheers,

Rob S

[Robs]

well i think its broken. Best i could just do is a 1:58.9 (granted its 01:40am but still).

The car is 4 wheel drifting the second i touch any bump/rumble strip and any high speed sideways movement, and is understeering a lot going into quick turns.

 

[Drift2XL]

How do you want an AWD to drive?

If you want it loose, I would lose much of the rear DF.

I have an AWD set up that is pretty much under all of my AWD cars. But I don't know how it would fare in online races. Its pretty much a hot lap deal, but its fast. It works real well on Tsukuba. Let me know if you want to try it.

Also, move the power back to the rears a little more. I like a 34/66 split. You may have to slim down the tire width a bit for more power. With an AWD on slicks, not as bad as the musclecars on DOTs.

How many laps are you looking at? If not many, increase camber up to at least -1.5 front and check to see if it needs more. I like to see the inside edge a good 8 to 10 degrees F hotter than the outside. The rears, I would go to -1.1 or a little more.

The slicks need more camber because the grip is larger and the tire "rolls over" more.

[Ske]

I'd actually tighten up the front diff quite a bit... try 60/30, the result might not be what you expected

And like Drift said, it's all about how you want the car to feel... and wheel users often want different traits than controller users. I prefer my ride to be confident, calm and stable...  I've got the spring/damper settings pretty much nailed for any car, but I'll still need to hunt for front end grip and general turn-in speed. I tend to use the front diff and alignment to achieve the former, and rear ARB strength to adjust the latter.

If my preference seems suitable to you, I can give you some numbers to work with... Check my last post in the "GT-Revisited" thread, those numbers work well as a starting point for AWDs. You might especially want to check out the damper settings I posted, as I feel those will seriously calm an "unwilling" car down (I currently use those numbers on ALL my tunes, heh)

[Robs]

thanks a lot for the replies, it helps a lot with understanding what changes make what effect.

Changed the following so far;

255 width tyres now not 275 and a Sport Block added, producing 406bhp/360lb-ft

Camber F -1.5 R -1.1
Diffs F 60%/30%
34%/66% power split
Dampers 7.1/6.5 6.4/4.4
Springs 486.8/405.6 <- a complete change from having the rear firmer than the front before
Height 4.3 / 4.5 (Ske, your GT-R was up at 6.6/6.8 but i presume that is just a higher car than this)
Aero F 80lb / R 70lb


After 5-6 laps did a 1:55.1 so improved by .4 of a second. So an improvement, but still a long way to go.

To be honest i suspect a lot of it is my driving, and me just not being fast, because 3 more seconds seems like a million miles away, unless their builds are built for speed and they are doing a lot more than 152mph at the start/finish line braking point.

Ske, i prefer stable cars, i think they are more raceable when actually racing, erattic 'skittish' cars imo don't translate to good racing vehicles, no matter how fast they are on a hot lap.

Drift, id like it to be as nimble but stable as possible, id rather have mild oversteer out of corners than a lack of front end grip as im used to driving muscles not AWD but thought id fancy a challenge

Thanks again for the help guys, any other coments?

[Spiny Anteater]

Nice paint job.

Like you,I used to run the feuerdog setup. I still use it as a base but then adjust accordingly. Personally I prefer my FWD and 4WD cars to have some oversteer built into the set-up so I can use the power to pull it straight if necessary so there's a limit to any advice I can give.

One thing which was pointed out to me a few challenges back (thanks to Hoplee and Serial) was that the bump settings in FD's calculator are pretty high. What I've started doing now is to calculate the rebound settings according to FD's calculator, then set the bump settings to half the figure for that end of the car. Try it, I did and immediately shaved half a second off at Sebring Club & Suzuka West.

Good luck in the race - looks fun.

[Drift2XL]

The first car I put it under was an AWD Integra. It was a handful. However, on the S998 EVO it was really stable.

The key is the toe. I put pos. .2 in the front and pos .5 in the rear. It really turns out on throttle. Just make sure you won't have to lift. Late turn lifts give a bit of understeer. You really have to pound on it to get the most of the rear steer.

It didn't really do anything really evil on Tsukuba with the EVO. In fact it was pefect.

The car just felt like the rear rotated around nice and controlled. And I really pounded the gas on it. You need to as a part throttle won't bring the rear around consistantly. And its not a drift style way out. Its like coming off with a muscle right on the edge.

[Robs]

Well first race has been and i finished a fluky 3rd out of 4 in the first race and dead last in the second lol.

Had a good laugh but these guys are all seriously quick and seemingly dont make a mistake ever, only reason i clinched 3rd was due to the 3rd place guys TV recorder change channel on him mid race resulting in him taking engine damage and me cruising past him.

Next course is Silverstone international, set a 1:26 after a few laps to aclimatise but i know theres a lot more in that just from driving before any tunes make a difference.

question, how do you make AWD cars not understeer in slow speed 180's and still stay stable through fast sweepers?

Cheers guys,

Rob

[Drift2XL]

A very good touch with the trailbraking. Running enough laps that you are starting to brake at the last possible foot. And really drivng it like a fool.

The avdantage to an AWD is the traction off, both the start and turns. The person that gets back to full throttle first and holds it the most, will have best lap times.

[Blooze]

I promised myself that I would have some input on this thread - probably a day late and a dollar short. 

My first impression?  "What a lard ass!"  Any car that starts out weighing damned near 4000 lbs. is suspect in my book.   But, we shall not judge prematurely - my Mom used to beat that into my head.  So I will build it and drive it.

First.  Is it Avon Slicks that are required, or Slicks in general that is required?

With the Forza body parts and the Avon Slicks I wound up with a B616 car.  Still plenty of room to improve.

How did you reach a final weight of less than 3000 pounds using only the Sport WR?  I couldn't do it.

Except for the rims.  Part of it is a thing in my head about unsprung weight, part of it is weight in general, and let's face it, some of it is purely subjective.  I think the Work Equip 03 look pretty cool.  I bought those.  It dropped 44 lbs, it cost 5 PI points.  We'll see...

Assuming that the weight thing was a typo, it left me at a 776 PI after all the handling upgrades - the rest goes to the engine...

Consider that 2800 lbs after all possible changes to weight, then the general consensus would be that it would be a good idea to improve the engine in such a way the torque was the focal point.  The stock Tq/Hp ratio is .888 - I will try not to hurt that.

So when it was all done and the pennies were counted, I wound up with 391 Hp, 347 Torque, and Toyo Slicks to get to a 2790 gross weight.  With no more input, or thinking... this puts the car at #3 on my A Class car list.  Of course, I haven't put it on the track yet.  We will try to reserve a little judgment to when we actually know what we are talking about.

So, I am off to buy parts - to paint a bit, and I will run a QR at the minimum on this rig.  Talk to ya then...

$

[Blooze]

Well, colour me surprized...  The Audi is now my top rated A Class car.   

2004 Audi S4 (V8)

• Hp: 391
• Tq: 247
• Wt: 2790

Rankings

Car	Quick	Flow	Twist	Power
2004 Audi S4 V8	185.420	144.510	142.418	183.501
1998 Subaru Impreza 22b STi	186.515	144.770	142.277	189.082

However, I am starting to wonder if I built the right car.  Here is the build and setup.

Parts

• Engine: Race exhaust and block
• Handling: All Race parts
• Tires: Sport Toyo; 275mm; 18"; Work Equip 03
• Body: Forza front and rear wings; Forza rear bumper

Gears

• FD = 3.76
• 1-6= 3.04   2.07   1.56   1.23   1.01   0.86

Setup

Parameter	Front	Rear
Weight Bias	55%
Tires	28	29
Camber	-1.1	-0.8
Toe	0.1	-0.1
Caster	5.1
ARB	+6% 10.01	+8% 12.57
Springs +3%	563.3	460.9
Height	4.2	4.3
Rebound	7.5	5.9
Bump	3.8	3.2
Aero	85	100
Brakes	50	104
Front Diff	58	40
Rear Diff	48	49
Torque	60/40

You can drive this one pretty hard.  It won't jump all over the place if you hit a rumble strip, but it is faster if you stay off 'em...

$

[Robs]

thanks for the input Blooze, much appreciated

I ended up with a 2nd and a 3rd at Silverstone and had a ball, but a lot of that was due to learning the track a lot more than mugello.

Tonight was Sunset Infield and i came 5th and 3rd (would of had 2nd but my girlfriend started puking up and distracted me!)

Car is currently a fair bit different, i decided i need the ponies over weight to keep up on the fast sunset banking.

Parts:-

All Race handling, and Sport Weight reduction
Race Intake
Race Exhaust
Street Fuel system
Race Cams & Valves
Race Block
Avon Slicks, stock width on 20" Fikse Profil 13's

Comes out at;

518 bhp
393 lb-ft
3365 lbs
53% Weight


No grip as ran it with lowest aero possible to keep up with the sprightly 2WD's but it might not of been the best idea.

Anyway, Laguna seca next week and im thinking a rebuild is on the cards, do folk think a full weight reduction tyre swop out or concentrate on keeping the torque as high as possible for the hill climbs?

will try your setup tomorrow mornin Blooze, looking forward to it handling properly!

many thanks,

Rob

[JG4tr]

Hey Robs, will you clarify something for us? In your first post you gave us what seemed like series regulation specs for the car...

Regulation Avon Racing Slicks, max width on 20" Volk GT-C's.
Front and rear Forza bumpers, and forza rear Wing
All Race platform apart from Weight Reduction, which is sport (final weight = 2825lbs)
Race Intake, Exhaust and Street Fuel system takes it to A850 with 391bhp/347lb-ft torque.

(Judging by the actual weight number, I have assumed, like Blooze, that this was actually Race reduction)
However, in later posts you mentioned going to narrower tires and less weight reduction so that you could add power. Would you clarify the build regulation guidelines for us??

After seeing Blooze's comment about the strength of this car relative to his other A class AWDs, I decided to add one to my stable as well. I built my first one out as a liteweight, grip tune with the only difference being that I used a couple of spare PI points to upgrade a couple of notches to the Kumho slicks.
I ran it at Suzuka in default trim for about 20 minutes to get a feel for the car, then loaded up Blooze's setup and ran for about 30 minutes.

Uh oh, looks like I have something to take care of here at my job. I'll come back to this a little later.

[Robs]

Sorry for not makig it very clear!

    * Cars do not need a BTCC design, but must have a racing style design
    * Cars must weight no less than 1150kg (excluding the VW Bora & Saab 9-3 Aero, which must weigh no less than 1100kg)
    * Maximum PI is 850
    * No upgraded turbos or chargers (except stock / turbos, no turbo upgrades allowed - intercooler upgrades are allowed)
    * Cars may be tuned to drivers preference
    * No drivetrain swaps
    * Dopey big spoiler is a must (for authenticity)
    * Tyres must be Racing Slicks, Avon Tyres, any width

Those are the league rules, so they must be Avon slicks but you can change the width and any parts between races, as long as it follows the above rules.

I tried bloozes tune on a power build at 516 bhp and it was okay but not any faster than my previious times on Laguna, but i then went full weight reduction and full width tyres and 391 bhp and i knocked 2 seconds of my lap time on my 3rd lap of free run!

[Ske]

Full grip tune seems to work better in most cases I think, especially since it also gives more confidence and consistency. Skinny tires and more power might have been the best for Sunset hotlaps, but a compromise gave me better average times.

A track like Laguna would most likely be best with an all out grip/weight build as brakes and turn-in response are the most crucial things around there, as far as I know. I also tend to favor HP over torque and compensate with gear tuning... Tuning gears for Laguna isn't as hard as it sounds.. you just have to make sure you don't find yourself wanting to change in the middle of a corner. I'll list some key spots to look out for.

- 2nd gear should be comfortable throughout T1+2 and at least until you've straightened out completely on the short straight.
- I also make sure I do not hit the limiter in 3rd before T3.
- The next issue is to make sure you can take T4 comfortably in one gear. I try and make 4th this gear.
- You might want to almost max out 5th before T5, then turn in early to keep momentum up and avoid dropping to 3rd.
- T6 is just like T5, you want to turn in early and straighten out early to avoid dropping to 3rd again.

This part is where I've found gearing to be most crucial.