Ford Sierra Cosworth RS500 - B Class tune help

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1

Hi all, I’m not really new to tuning in forza but I am still struggling to get a grasp of what does what etc.

I am determined to make this car faster around brands hatch GP but I spent all night last night tweaking it and couldn’t get it any better.
It feels like its pushing on too much in corner entry, as soon as i touch the throttle mid corner, the diff takes over and it gets a nice exit.

fastest lap i could get was a 1.39 which isn’t bad but i know it can be better.

I found that going one step up on the rear tyre width seemed to help the feel but then i ended up with a tune that saw the rear higher and stiffer than the front.

I will post my full setup here if anyone would be willing to try it and give me some tips?

PARTS:

Everything is stock unless noted otherwise.

Engine:
Exhaust - Race
Camshaft - Sport
displacement - Race

Platform & Handling:

Everything Race other than roll cage which is stock.

Drivetrain:

Transmission - Street
Driveline - Sport
Diff - Race

Tyres & Rims

Tyre Compound - Street
Front width - 235/40/16
Rear Width - 245/35/16
Rims - HRE P43sc
Rim size - 16"

Aero:

Full adjustable front and rear~

Tuning

Tyres:
Front - 28.5
Rear - 28.5

Alignment
Camber front: 4.2
Camber rear: 3.4
Toe front: 0.2
Toe rear: -0.2
Front caster: 4.0

ARB’s
front: 23.02
rear: 26.11

Springs
front: 429.9
rear: 480.0
ride height front: 4.6
ride height rear: 4.8

Damping
Rebound front: 10.5
rebound rear: 10.5

bump front: 3.0
bump rear: 3.0

Aero
front: 100
rear: 190

Brake
balance: 50%
pressure: 110%

Differential
Acceleration: 32%
Deceleration: 16%

Thats it.
My main point of confusion is damping, I see so many conflicting tunes, some people max rebound and min bump, I find this too much, when you brake the car nose dives and bounces, also seems a little too skittish and slidy. Really struggle to find a sweet spot with damping.
Also camber, because i’m not sure on my other settings, i struggle to find the sweet spot with camber because it could be something else making it slide…

Any tips much appreciated.

Thanks

2

Hi,

As for your build I would suggest replacing camshaft and displacement with other upgrades like air filter etc as this usually gives you a faster setup.

Concerning tuning help:
Your alignment seems way off usual settings and your ARBs seem to stiff in relation to springs.

If you provide me weight and weight distribution and I can come up with suggested values.

Fifty

3

Thanks.

I have just been fiddling with ARB’s I literally cut the values in half and then added a little to the rear and straight away was a great improvement.
I’m still not lapping any faster, but the car definitely turns better.

weight is 2242lbs and 51% front weight distribution.

i was just reading a guide about setting spring rates with a calculator like so…

51% of 2242 is 1143.4, divide this by 2 which is 571.7, this would be front spring rate.

however i am a bit skeptical of this method just because it’s not definitive, its just the spring rate

all this means is that with the weight of the car on these springs, it will sit down by exactly an inch…

just looking for what people use that is proven to work well :slight_smile:

4

I gave it a spin, and it isn’t too bad actually. Looking at the camber settings I was actually rather surprised that it turned in that well.

Anyhow how I see things on that tune.

Alignment

Reduce camber a LOT. Personally I barely ever go over 2.5 and those are rather extreme cases when I do.
I’d say -1.5/-7 is enough, althuog bit higher won’t hurt it.

Remove Toe I don’t see that necessary in this car. -0.1 on rear if needed, is quite enough.

Caster, I usually prefer higer caster, but that might be due how I’m used to do things.

ARB

Soften antirollbars both front and back, Gives you bit more stability while turning.

Suspension

Soften the rear suspension, Gives you bit more grip on corner exit,

Lift the front suspension, Currently it tends to get bouncy (bottoming out) on kerbs.

Rebound

It’s not terrible, but softening it a bit would give more grip.
I’d suggest exploring 9.5 to 10.3 region on rebound (Front softer than rear)
and 2.0 to 2.5 region on bump (Front stiffer than rear)

Brakes

Brake bias to 48% which will give you slightly better turn in.

Personally I’d go bit more aggressive differential, Just a bit.

I shaved about 0.8 seconds with those adjustments.

Build
Here I could see another second being shaved.

Just by losing Camshaft, and replacing it with
Race Intake
Race Valves
Sport Pistons

you will gain
8 hp
20 lb-ft
and lose
8lbs

Also it improves your gearing as the 2nd turn of brands I was constantly shifting to 1st as 2nd was “too long” for the turn.

And then there is still one thing. This car has 5.7l V8 swap which is quite literally overpowered engine.

Using 5.7 V8
Street exhaust
Race Driveline
front tire width 245

I was able to shave almost 1.5 seconds off, And while the car was bit too oversteery with this engine, and one tire fires were frequant, (Needs more agressive differential, and more fornt biased brakes)

5

Thanks very much for you replies.

I have taken what you said into consideration and will give it a try now.

i’m not a big fan of the V8 swap in this car mainly because its a sierra cosworth lol.
the main reason i wanted to get this car handling well on brands GP is because thats what they did back in the day and they didn’t use a V8 :stuck_out_tongue:

6

Well to be honest, I hate to swap it in everything, so I try to avoid it too. How ever it is probably the best engine in game, and that’s why I advice to swap in to it.

How ever I gave you the build for the stock engine I shaved about 0.5 sec with that build compared to your build. and it was easier to drive as the gears match up far better than the build with camshafts

7

So this is what ive got at the mo which is definitely better,

got rid of camshaft and did other upgrades as mentioned.

camber -1.5, 0.7
toe 0,0
caster 5.0

ARB front 10
ARB rear 14

I then used a calculation to do the spring rates.
new weight is 2222lbs with 51% weight distribution.

front is 1133.2 / 2 = 566.1
rear is 1088.8 / 2 = 544.4

This still feels a little understeery so i evened the spring rates to 555 each.
This could possible be down to the rear tyres being a step wider than the front.

I usually prefer drifting rather than lapping, so naturally I have a preference for oversteer and a soft loose car.

This setup feels a little stiff to me, but if i soften the springs any more there is too much roll, if i stiffen the ARB’s to counter that, it doesn’t turn…
I seem to hit this same obstacle in most of my tunes.

8

Hi,

try following setup:

Tires: 28.0/28.0
Springs: 531.5/440.4
Camber: -2.6/-2.2
Toe: 0.0/0.0
Caster: 5.0
ARBs: 16.85/16.18
Rebound: 7.9/7.6
Bump: 4.5/4.3
Diff: 70/35
Brakes: 48%/125%

Fifty

9

Small lean isn’t actually all that bad even in circuit car.
But you could try putting 235’s at the back and lighter rims, or race driveline, which would “balance” the car

10

Fixed springs and rebound in original post.

11

Thanks for that, I have just put that setup on, and I am impressed.
This feels a lot more stable. I may just lose a little off the front spring rate as I like a little bit more bias towards oversteer but a very good setup thanks.

Just before you posted that i managed to get the car driving the best its been so far and was hitting low 1.38 and still improving, i saved it and went to these settings and am getting almost identical times.

Must admit i do usually use very similar camber settings to you which i was starting to lose faith in lol.

12

Lol you read my mind ^

13

So how are you getting along with the updated tune?

14

I’ll have a look at this when I’m next on. I love that car.

15

Looking at your tune no were near my tuning style for the car I’m only guessing by the stats it’s a handling build wrong for that car in my opinion the best build is 6.4 speed 5.2 handling 8.2 acceleration 5.2 braking with 3.7 engine that’s all I’m saying best advice I can give you is every car in forza is ether best at grip build power build and alround build each car is best in these categories in this case your better off making it a around build trust me ps PR IW1NNUMBER1

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