Forza 2 tips and tricks

[gellar]

Good post from NASIOC:

TO REDUCE UNDERSTEER or INCREASE OVERSTEER:

Front tires:
- Increase tire pressure in 2.5psi increments
- Increase Section Width
- Lower the Aspect Ratio
- Reduce front tread depth

Rear Tires:
- Reduce tire pressure in 2.5psi increments
- Reduce section width
- Install higher aspect ratio tires
- Increase rear tread depth

Front Wheels:
- Install wider wheels
- Install lighter wheels

Rear Wheels:
- Install narrower wheels
- Install heavier wheels

Front Alignment settings:
- Dial in more negative camber
- Dial in More toe-out
- Dial in more positive caster

Rear Alignment settings:
- Dial in more positive camber
- Dial in more toe-out (Same as front)

Anti-Sway bars:
- Soften the Front
- Stiffen the Rear

Spring rates:
- Soften the Front
- Stiffen the Rear

Shock absorbers:
- Soften the Front
- Stiffen the Rear

Suspension Bushings:
- Soften the Front
- Stiffen the Rear

Brake Proportioning
- Reduce Front brake pressure
- Increase rear pressure

Weight Distribution
- Reduce front weight
- Increase rear weight

Aerodynamics:
- Increase Front Downforce
- Reduce rear downforce

---------------------------------------------------------------------------------

TO REDUCE OVERSTEER or INCREASE UNDERSTEER:

Front tires:
- Decrease tire pressure in 2.5psi increments
- Decrease Section Width
- Install higher Aspect Ratio tires
- Increase front tread depth

Rear Tires:
- Increase tire pressure in 2.5psi increments
- Increase section width
- Reduce aspect ratio
- Decrease rear tread depth

Front Wheels:
- Install narrower wheels
- Install heavier wheels

Rear Wheels:
- Install wider wheels
- Install lighter wheels

Front Alignment settings:
- Dial in less negative camber
- Dial in less toe-out (to toe-in if needed)
- Dial in less positive caster

Rear Alignment settings:
- Dial in less positive camber
- Dial in less toe-out (Same as front)

Anti-Sway bars:
- Stiffen the Front
- Soften the Rear

Spring rates:
- Stiffen the Front
- Soften the Rear

Shock absorbers:
- Stiffen the Front
- Soften the Rear

Suspension Bushings:
- Stiffen the Front
- Soften the Rear

Brake Proportioning
- Increase Front brake pressure
- Reduce rear brake pressure

Weight Distribution
- Increase front weight
- Decrease rear weight

Aerodynamics:
- Reduce Front Downforce
- Increase rear downforce

gellar

[EngineNo9]

Gellar, the one thing I notice is that your little tip sheet there says to increase/decrease your tire pressure by 2.5 PSI each time.  Forza only goes by single PSI increments from what I've seen, and even then changing just one or two PSI can be a pretty big increase or decrease in handling. 

[gellar]

Gellar, the one thing I notice is that your little tip sheet there says to increase/decrease your tire pressure by 2.5 PSI each time.  Forza only goes by single PSI increments from what I've seen, and even then changing just one or two PSI can be a pretty big increase or decrease in handling. 

Oh yeah... these settings weren't originally meant for Forza, they were actually in a Suspenion Tips and Tricks thread for real life Auto-X... I just copied and pasted them because I thought they'd be useful.

gellar

[JuniorDan]

Gellar, the one thing I notice is that your little tip sheet there says to increase/decrease your tire pressure by 2.5 PSI each time.  Forza only goes by single PSI increments from what I've seen, and even then changing just one or two PSI can be a pretty big increase or decrease in handling. 

Oh yeah... these settings weren't originally meant for Forza, they were actually in a Suspenion Tips and Tricks thread for real life Auto-X... I just copied and pasted them because I thought they'd be useful.

gellar

This is a good way to start a Monday mourning. I too taught you got this from an official Forza 1or2 tips and tricks.   

[IkeVandergraaf]

Ok, question on tuning the transmission.  Do you tune all the gears or just the final gear?  Somebody was saying that it's pretty easy and there's some deal with looking at some graph?  Help.

Regarding tuning, here is a moderately useful link from the official site.

Oh, and dammit, I missed my thousandth post.

[wonderpug]

Ok, question on tuning the transmission.  Do you tune all the gears or just the final gear?  Somebody was saying that it's pretty easy and there's some deal with looking at some graph?  Help.

Power, Torque, Dyno Graph 101:

Dyno Graph - When you buy engine upgrades in Forza, you'll see a graph of your engine's power raising and lowering according to your changes.  This is the equivalent of a "dyno graph," which real life car tuners obtain from running their car on a dynometer.  A dynometer is a platform you park your car on that has a pair of big cylinders that your car's tires rest on, sort of a car treadmill.  You bring the car up to speed and then floor it while the dyno measures your power over your RPM range.  The result is a dyno graph like we see in the game, which charts your horsepower and torque.

Torque - Torque is your engine's twisting power.  This is the real measurement of your engine's strength, in each gear you're going to be getting the most acceleration where the torque is the highest.  So why should we care about horsepower?

Horsepower - Horsepower is "power," or your energy delivered over time.  Essentially, it means how fast your torque is getting delivered to your tires.  For cars, time = RPM.    So the torque is the raw energy of your car, but the horsepower lets you see how fast that energy is being delivered to your tires.  So when your torque is at its peak, your HP won't be its highest because the engine isn't spinning fast enough to quickly deliver that energy.  To the right of your torque peak, although you're getting less energy, your engine is spinning faster in proportion to the loss, so you're gaining more power (HP) overall, maxxing out at your HP peak.  Past your HP peak, your torque is decreasing more than your increased RPM is compensating for, so your HP starts to drop.

How to read the graph - Since the equation for horsepower is: HP = torque * RPM / 5250, your HP and torque curves are always going to meet at 5250 RPM.  Your power band, or your car's "sweet spot" is generally going to be the RPM range from a bit before your torque peaks, to a bit after your HP peaks.  This is the range you want your tachometer to be in for most of the race.  For a naturally aspirated engine, the curve is usually much broader, giving you a wide range of useable RPM.  For a turbocharged engine, the curve is usually shifted much more towards the higher range, with a smaller "sweet spot." 

Upgrading - As you pick and choose your engine upgrades, keep an eye on how it changes the graph.  Changing your intake or exhaust is generally going to give you more power overall, shifting the entire curve up.  This is nice and reliable, as you're getting more power across the board without changing your car's characteristics too much.  Adding a turbo, or adding a bigger turbo, is generally going to increase just the high end of the graph, meaning that your "sweet spot" is now in a higher RPM range.  With this kind of upgrade, you'll want to make sure to change your gearing to better take advantage of this new power curve.

Tuning - Once we obtain our power band (reminder: RPM range from just before your torque peak to just after your HP peak) we turn to the gear ratios.  The Y-axis of the gear ratio chart shows the RPMs, while the X-axis shows the speed of the car.  The X-axis is the easiest, change your final gear ratio so that your highest gear doesn't stretch to the right of the highest speed you need to go.  For the Y-axis, we want the white lines for each gear to match up with our power band, so if our power band is from 5k-7k RPM, we want each line to likewise go from 5k-7k.  A turbocharged car will often have a very narrow power band, very high in the RPM range.  It'll likely move very quickly through the gears in order to keep the engine in, say, the 8-9k range.  A naturally aspirated car, especially something like a classic American muscle car, is going to have a much broader range and might not have to shift through the gears nearly as quickly.

"I hear you can get better times if you use manual transmission, why?"  There are other advantages to manually shifting, but I'll stick to what's most applicable to the power curve.  The game's automatic transmission will shift as far into the red line as possible.  For some high revving high pitched whining turbocharged car, this might be ok, but for many other cars (American muscle, I'm looking at you) the red line might be well past the car's power band.  Sure, your 800hp Shelby Mustang beast can go up to 9k RPM, but if your power band ends at 7500RPM then you're not accomplishing anything.  You're better off shifting at 7500RPM (well short of your red line) and bringing your engine back all the way down to 3000RPM which is well within your power band.

Whew, ok, short version:

Power band = RPM range from torque peak to HP peak, you want to tune your gears to keep you in this range as much as possible.  Also, tune your final gear ratio so that your last gear red lines at the highest speed you need.  Having a 6th gear that goes to 200mph isn't going to do anything for you if you never go past 150mph in the races you're running.

[Harkonis]

I'm reviewing some of the vids I've recorded to see if I can figure out using the telemetry what some of our less skilled brethren are doing differently.

[Chaz]

Awesome.  That's exactly the kind of writeup I need in order to actually make some movement on learning to tune.  Thanks, Pug!

Also, kudos for being the first person to actually explain why manual shifting is better than auto.  Knowing that, I might actually try manual transmission.

[Harkonis]

I'd like to see a process where we could have a car picked, someone upgrade it and disect why they did what they did.  Then someone tune it and run through why they did what they did, then actually gift the car around the group so we can each try that exact car setup and see why it is the way it is.  Might be an eye opener to some of the starting upgraders and drivers.

[Harkonis]

Awesome.  That's exactly the kind of writeup I need in order to actually make some movement on learning to tune.  Thanks, Pug!

Also, kudos for being the first person to actually explain why manual shifting is better than auto.  Knowing that, I might actually try manual transmission.

It's also possible to downshift before or during a turn to have better control over the car and more 'juice' on exit and you can't do that with an auto.  Now if only the game would stop adding an extra downshift to me at random. 

Always remember that the exit of a turn is far more important than the entry. Regardless of how you enter a turn, if you can exit it smoothly you will cover the next distance much faster. 

I'd suggest anyone go into free run, run a couple laps as best they know how, then run a lap breaking early and coasting through the turn so they get a smooth exit and compare times. I was amazed that when I drove it in the more relaxed manner I was actually turning faster laps than when I drove it hard into turns and out of them.

[JuniorDan]

I'm reviewing some of the vids I've recorded to see if I can figure out using the telemetry what some of our less skilled brethren are doing differently.

anything on depwards strange driving last night?  I think it was depward....right?

[JuniorDan]

Awesome.  That's exactly the kind of writeup I need in order to actually make some movement on learning to tune.  Thanks, Pug!

Also, kudos for being the first person to actually explain why manual shifting is better than auto.  Knowing that, I might actually try manual transmission.

It's also possible to downshift before or during a turn to have better control over the car and more 'juice' on exit and you can't do that with an auto.  Now if only the game would stop adding an extra downshift to me at random. 

Always remember that the exit of a turn is far more important than the entry. Regardless of how you enter a turn, if you can exit it smoothly you will cover the next distance much faster. 

I'd suggest anyone go into free run, run a couple laps as best they know how, then run a lap breaking early and coasting through the turn so they get a smooth exit and compare times. I was amazed that when I drove it in the more relaxed manner I was actually turning faster laps than when I drove it hard into turns and out of them.

To add to this I would also recommend using the replay or forza TV and watch other drivers with the Telemetry on. You can see when they gas, break, turn radius on the wheel, speed etc. Then do as Hark said to feel it for you self. Worked for me..... 

[Harkonis]

I'm reviewing some of the vids I've recorded to see if I can figure out using the telemetry what some of our less skilled brethren are doing differently.

anything on depwards strange driving last night?  I think it was depward....right?

I think it was disarm, I watched it later and watching the telemetry his steering input was going left to right and he was swerving.  The first time you two hit, he swerved over on you, the second time it was all your fault and you plowed him

Lag doesn't show the actual steering column inputs so I think it was a case of thinking you're going straight while making small adjustments on the controller.  Watching some of these replays I'm noticing a lot more movement than previously expected when you compare wheel vs stick drivers.

[JuniorDan]

  oops

[IkeVandergraaf]

Wonderpug, thank you.

Thank you, thank you, thank you, thank you, thank you.

Now explain the suspension and wheel alignment to me.

[wonderpug]

The Importance of Exit Speed, the physics:

So why is the exit speed of a turn so gorram important?  The short version is that your speed at the exit of the turn is going to be amplified by the length of the straight after the turn.  Here's the mathematical explanation:

Let's say we have two identical cars that accelerate at a flat 5 meters/second/second.  Average cars accelerate somewhere around 3-4m/s/s, so our car is pretty good.

We have a turn followed by a long straight.  Car 1 exits the turn at 25mph (11.25m/s), Car 2 exits just slightly faster, at 30mph (13.5m/s).

Our distance travelled (d) is equal to our starting speed (v) times time (t), plus 1/2 acceleration (a) times time squared (t^2)
d = vt + .5*a*t^2

Code:

Elapsed Time   Car 1 distance   Car 2 distance   Difference (m)   Difference (ft)
1s                  12.5m              17.5m              5m             16.4ft
3s                  52.5m              67.5m             15m             49.2ft
5s                 112.5m             137.5m             25m             82.0ft
7s                 192.5m             227.5m             35m            114.8ft
10s                350.0m             400.0m             50m            164.0ft

After just 3 seconds, that 5mph difference exiting the turn has given Car 2 a 50 foot lead.  Even though they're accelerating at exactly the same rate, at 5 seconds the distance between them increases to 82 feet, and after 10 seconds Car 2 is a whopping 164 feet ahead.

Same exact car, same exact acceleration, but by leaving the turn just 5mph faster, Car 2 has gained a big advantage.  If they keep this up over many turns over several laps, Car 2 is going to win by a big margin even though he's driving the exact same car.

So every time you come up to a turn, you should be thinking about what you can do to make your speed as fast as possible when you exit.  If there's a series of turns one after another, you want to plan your line through the first turns to give you the biggest advantage exiting the last turn.  In a 3 turn series, even if you have to take the first two at completely odd angles, if it lines you up for a speedy exit in the 3rd turn, it's going to give you a better lap time.

You know how they say a race is won in the turns?  This is why.

[IkeVandergraaf]

Now if only the game would stop adding an extra downshift to me at random. 

Are you using the wheel Hark?  That's happened to me a couple of times also.  Generally fucks my engine when it happens.

[Brendan]

One of the Turn10 guys wrote up a quick guide to some of the tuning parameters (and how wheel vs. gamepad might affect your settings):

http://forums.forzamotorsport.net/blogs/post.aspx?App=turn_10s_forza_motorsport_blog&y=2007&m=06&d=08&PostID=230749

None of the cars in Forza 2 require a great deal of tuning.  The default setups are 85-90% good… but 10-15% of time is HUGE on a race track.  So, there is significant advantage to be gained by tuning your car.

Bang for buck:

Gear Ratios  (almost always too long… you lose acceleration for sake of top speed you never hit).   Gear car so you hit the last gear (5th or 6th) at red-line at the end of the longest straight away.  Then you’ll be setup well for acceleration (make sure to get clutch & tranny upgrades if you do this though since you’ll be shifting more often).


Downforce – I use GOBS of downforce.   I’m slower in a straight (and you can pass me there) but I’ll kill you in the corners.  Get it, use it, love it.
Dealing with oversteer and understeer: To increase understeer (same as decreasing oversteer) push all the “Front” sliders to the right just a little (bigger values) and reduce “Rear” sliders to the left (lower values) about an equal amount. Try to move sliders in both/opposing directions until you get a neutral car… I.e. if you’re going to add +5% to spring rate in the front, subtract -5% from the rear.  Add +5% to the bump stops and rebound for the front, and subtract 5% from the bump stops and rebound for the rear.   Think symmetry and you’ll stay “safe”.

Camber and caster: Next deal with camber and caster. These affect the "turn in" speeds of the car. You get better turn in the bigger these values are, but you reduce the traction-patch, so your braking is worse and your tires wear/heat up excessively on the insides. But you get better grip in turns… guess which Albus likes?   Grip in turns.  So I add camber and caster on all my setups.

Toe-in-out:  You can mess with Toe… most people don’t. Think of your tires like your feet, if you are bow-legged and your toes point away from your ankles, that’s “toe out”.  If you are “pigeon toed” (toes point towards each other) that’s Toe-in.  Toe-in helps you get bite on corner entry.   Toe-out adds stability to a “rowdy” back end (oversteer).  Keep in mind that any degrees of input here actually slow you down in a straight line… you’re creating “rolling friction” for sake of stability and better turn in.  Other elite drivers don’t have use any or much “toe”… I actually use it to gain stability.   My “speed” is not about quickness but consistency.  You can win the best lap of the race… I just want to win the race.

Brake balance/pressure:  I play with these but most folks don’t.   I actually like reducing the brake pressure 5-10%... it helps me (manual braker using a wheel) not lock-up as much.   Brake balance is very car specific… in a long wheel-base car 50/50 is fine, you can even push it forward a bit (better braking, a little less stable back-end under braking) but if you have a short wheel-base car, I like to add +1 or +2% rear brake balance which helps keep the car’s rear end from wanting to switch ends with the front when you brake and turn at the same time (which I do a lot as I “trail brake”).   If you’re ever past 5% from 50/50 you’ve probably gone too far.

All that being said… here’s my best tuning advice…

Go to Multiplayer Leaderboards, find the car you want to tune (in the appropriate class) and download setups (from the people honorable enough to post them) and “tweak”… anyone on the leaderboard (Top 10) probably had to do some amount of tuning (or plagiarizing) to get where they are. Leverage their tuning ability and try out their setups. If you don’t like it, try someone else’s… almost assuredly, you’ll find a setup that “feels good”… now go look for more setups by that person and in other cars and classes… they will probably feel similar.

I know that my Albus setups have a very similar flavor/feel because I want my cars to behave very similarly.  I like a touch of understeer while many other fast drivers favor what I would consider aggressive amounts of oversteer. I drive with an MS FFB wheel, many other drivers use a gamepad. With a gamepad you can catch an oversteering car much more easily than you can with a wheel. Hence, their ability to deal with aggressive amounts of oversteer. With a wheel you can handle high-speed turns/sweepers much more delicately than a game pad user can so I can be more precise/consistent. So, even though guys might be right next to each other (with the same car) on a leaderboard, they could have very different feeling setups.   Find a “personality” you like in a setup and then explore with minor changes… you might create something of your own that works even better for you.

That’s my quick ‘bang for the buck’ primer on tuning.

[wonderpug]

If anyone's a little fuzzy on the concept of understeer, I dove into the time trials for the first time last night and there's a perfect example of understeer right at the beginning.

In one of the first two time trial races in arcade mode (I think it's the very first one) they have you driving a front wheel drive Ford Focus on a track that has some long turns.  Take the Focus for a run, start into the turn, and when you're in the middle of the turn really give it some gas.  You'll find that instead of your back end sliding you out into a spin like you might be used to, you'll plow right off the outside edge of the turn.

The reason understeer like this is so common with front wheel drive cars, (and often with all wheel drive cars), is that your front tires are already doing double duty in the turn.  They're both working to keep you turning, and they're being used for any acceleration you're trying to do.  If you overdo it on the acceleration, they lose traction and can no longer help you steer, thus you plow towards the outside edge instead of keeping in the turn.  And that's understeer.

[JuniorDan]

The Importance of Exit Speed, the physics:

So why is the exit speed of a turn so gorram important?  The short version is that your speed at the exit of the turn is going to be amplified by the length of the straight after the turn.  Here's the mathematical explanation:

Let's say we have two identical cars that accelerate at a flat 5 meters/second/second.  Average cars accelerate somewhere around 3-4m/s/s, so our car is pretty good.

We have a turn followed by a long straight.  Car 1 exits the turn at 25mph (11.25m/s), Car 2 exits just slightly faster, at 30mph (13.5m/s).

Our distance travelled (d) is equal to our starting speed (v) times time (t), plus 1/2 acceleration (a) times time squared (t^2)
d = vt + .5*a*t^2

Code:

Elapsed Time   Car 1 distance   Car 2 distance   Difference (m)   Difference (ft)
1s                  12.5m              17.5m              5m             16.4ft
3s                  52.5m              67.5m             15m             49.2ft
5s                 112.5m             137.5m             25m             82.0ft
7s                 192.5m             227.5m             35m            114.8ft
10s                350.0m             400.0m             50m            164.0ft

Wait.............So.....car 2 wins because he was able to accelerate at an earlier point than car 1?
So taking a turn wide and cutting the edge on exit is better ?
Because if you follow most on the breaking lines your hugging the inside you get a shorter line on exit..right?

[JuniorDan]

If anyone's a little fuzzy on the concept of understeer, I dove into the time trials for the first time last night and there's a perfect example of understeer right at the beginning.

In one of the first two time trial races in arcade mode (I think it's the very first one) they have you driving a front wheel drive Ford Focus on a track that has some long turns.  Take the Focus for a run, start into the turn, and when you're in the middle of the turn really give it some gas.  You'll find that instead of your back end sliding you out into a spin like you might be used to, you'll plow right off the outside edge of the turn.

The reason understeer like this is so common with front wheel drive cars, (and often with all wheel drive cars), is that your front tires are already doing double duty in the turn.  They're both working to keep you turning, and they're being used for any acceleration you're trying to do.  If you overdo it on the acceleration, they lose traction and can no longer help you steer, thus you plow towards the outside edge instead of keeping in the turn.  And that's understeer.

Whats the Fix??
Also last night I was doing the Corvette races, I went the the 2002 back one you win I forgot where. I supped it up to like 10speed, 8.6accel, a 6.4for breaking, and 5.1Handeling. give or take. Car topped out at 241mph. However the car could not be controlled, I tunned and tested till I couldn't anymore. On the straights the rear of the car acted like it wanted to pass the front it would stat fishtailing with no controller input. Let not even talk about making a turn...just wouldn't happen. Is the car just to fast for this type of racing? I cant even say it could drag race because it cant even hold a straight line...... What are the tuning recommendations for this? 

[Booner]

You always want to make the smoothest arc possible from the outside of the turn, to the inside at the apex, then back to the outside on the exit. You keep your maximum velocity this way and minimise the chance of spiking your lateral Gs and swaping ends.

Edit:

Juniordan, that's alot of power for that handling rating. I haven't found a track other than the Nissan Raceway that could use that kinda top end. I would tune that beast down and work on getting it to handle better...then start bumping the power up bit by bit, until it's just on the edge.

Also...found this that gives a brief description of the racing line.

[IkeVandergraaf]

Wait.............So.....car 2 wins because he was able to accelerate at an earlier point than car 1?
So taking a turn wide and cutting the edge on exit is better ?
Because if you follow most on the breaking lines your hugging the inside you get a shorter line on exit..right?

Sort of.  Following the braking line generally follows the shallowest curve, allowing you to brake as little as possible and lose as little speed as possible, allowing you to come out of the curve at a higher speed and allowing you to start accelerating a little sooner.  It's not entirely accelerating at an earlier point than car 1 though.  Even if you accelerate at the same point as car 1, so long as you're doing so at a higher speed that car 1 you still get the benefits.

[IkeVandergraaf]

More gearing questions:

What's redline mean?  Is that the maximum RPM the engine will put out, or is that when the tachometer goes into that red zone?

Is there any way to see the power curve other than by going to the upgrade engine screens?  Some of the cars don't let you buy upgrades, so how do you see the curves for those?  I know that there's a car info screen accessed from the car select menu that tells you the torque RPM, HP RPM and redline RPM.  I assume the first two are the RPMs for peak torque and HP, but don't know for sure.

[Booner]

More gearing questions:

What's redline mean?  Is that the maximum RPM the engine will put out, or is that when the tachometer goes into that red zone.

I know that there's a car info screen accessed from the car select menu that tells you the torque RPM, HP RPM and redline RPM.  I assume the first two are the RPMs for peak torque and HP, but don't know for sure.

Yeah, redline is the max RPM the motor can make without damage. I'd assume that the info sreeen would note peak torque and HP.

[wonderpug]

Wait.............So.....car 2 wins because he was able to accelerate at an earlier point than car 1?
So taking a turn wide and cutting the edge on exit is better ?
Because if you follow most on the breaking lines your hugging the inside you get a shorter line on exit..right?

Car 2 could be going 5mph faster out the turn because he accelerated earlier.  This could have been from entering the turn slower, or by having a later apex than Car 1.  The 5mph difference could be brought about other ways as well.  Maybe they took the same line but Car 1 rode on the bumps on the inside curb a bit too much.  Maybe Car 1 didn't turn the steering wheel as smoothly and his tires squealed just a bit more on the turn.

Whats the Fix [to understeer]??

Gellar posted a list with a bunch of over/understeer corrections.  To reduce understeer, soften front shocks/stiffen rear shocks, lower front end/raise rear end, soften front sway bar/stiffen rear, raise rear tire pressure/lower front, or simply drive differently and take a different line.

Also last night I was doing the Corvette races, I went the the 2002 back one you win I forgot where. I supped it up to like 10speed, 8.6accel, a 6.4for breaking, and 5.1Handeling. give or take. Car topped out at 241mph. However the car could not be controlled, I tunned and tested till I couldn't anymore. On the straights the rear of the car acted like it wanted to pass the front it would stat fishtailing with no controller input. Let not even talk about making a turn...just wouldn't happen. Is the car just to fast for this type of racing? I cant even say it could drag race because it cant even hold a straight line...... What are the tuning recommendations for this? 

If you create a monster like this, there's a few things you can do to tame it.  One, upgrade the tires by improving the tire compound and/or making the tires wider.  I really wish the game would let you have different sizes and compounds in the front and back.  Two, add a rear wing and tune to add a lot of downforce to try and keep that rear end on the ground.  Three, if you took some of the weight reduction options, think about undoing them.  The extra weight can help you stay on the ground.

You always want to make the smoothest arc possible from the outside of the turn, to the inside at the apex, then back to the outside on the exit. You keep your maximum velocity this way and minimise the chance of spiking your lateral Gs and swaping ends.

Another thing to remember is that the apex is not a set point on the track.   It's easy to look at a turn and assume the apex is the point right in the middle, but most of the time a late apex is preferred.  A late apex pushes the apex (the point where you're closest to the inside of the turn) closer to the end of the turn.  This shape goes hand in hand with the "slow in, fast out" philosophy, as the late apex means you were taking a sharper, slower turn at the beginning in order to have a less sharp, faster turn at the exit, thus getting on the accelerator sooner.

[Booner]

You always want to make the smoothest arc possible from the outside of the turn, to the inside at the apex, then back to the outside on the exit. You keep your maximum velocity this way and minimise the chance of spiking your lateral Gs and swaping ends.

Another thing to remember is that the apex is not a set point on the track.   It's easy to look at a turn and assume the apex is the point right in the middle, but most of the time a late apex is preferred.  A late apex pushes the apex (the point where you're closest to the inside of the turn) closer to the end of the turn.  This shape goes hand in hand with the "slow in, fast out" philosophy, as the late apex means you were taking a sharper, slower turn at the beginning in order to have a less sharp, faster turn at the exit, thus getting on the accelerator sooner.

Would you real go for the late apex on a symmetrical turn? It seems that you'd keep your velocity much higher through the whole thing and exit even or even faster with a smooth arc.

[gellar]

You always want to make the smoothest arc possible from the outside of the turn, to the inside at the apex, then back to the outside on the exit. You keep your maximum velocity this way and minimise the chance of spiking your lateral Gs and swaping ends.

Another thing to remember is that the apex is not a set point on the track.   It's easy to look at a turn and assume the apex is the point right in the middle, but most of the time a late apex is preferred.  A late apex pushes the apex (the point where you're closest to the inside of the turn) closer to the end of the turn.  This shape goes hand in hand with the "slow in, fast out" philosophy, as the late apex means you were taking a sharper, slower turn at the beginning in order to have a less sharp, faster turn at the exit, thus getting on the accelerator sooner.

Would you real go for the late apex on a symmetrical turn? It seems that you'd keep your velocity much higher through the whole thing and exit even or even faster with a smooth arc.

It depends ENTIRELY on what your goal is.  If you are hotlapping alone, there is really just one proper line around the track and it's fairly textbook with standard apexes and such.  However, if you are racing, your goal is totally different.  At that point, your goal is not necessarily to have the fastest laptime, but to be faster in the passing zones than your opponent. 

If I am leading a race, I will purposefully take a turn 'incorrect' and screw with the apex because I know two things: a) my opponent will not want to run that line and thus have to adjust, forcing him to react as to when he can hit the throttle, and b) I can take away passing zones.  If anyone has raced against me, you'll notice that if I am defending a position, I'll more than likely be driving  on the inside of the ideal line and late or early apex the turn so I can hit the throttle where/when I want to.  Now on occasion, someone will tag me from the rear if I do this, but generally speaking I'm going to assume that the guy trying to chase me down isn't a retard and knows not to do that.

If I am chasing someone else down, I know exactly where I want to pass.  I spend the entire lap setting up for a pass into the turn at the end of the longest straight.  I will follow and try to force a mistake up until that point, but once we get to the turn before the longest straight, I provide enough space where I can early apex the turn and jump on the throttle way earlier than the guy I am trying to pass (as wonderpug describes above).  This means that given equal cars, I will carry more speed down the straight and into the turn, so given my superior car control , I can outbrake the opponent into the turn.  Even better, as I tend to setup my cars more on the power than handling side, I generally have more horsepower than most cars on the track and can sometimes even complete the pass during the straight.

Hope that makes sense.

gellar

[Booner]

Aye, very much so.

I rarely end up in the pack, so driving strategy is something I rarely think of. I'm either trying turn the best times to stay ahead or trying to catch the ones that have passed me because I've made a mistake.

I guess I need to get online and keep these things in mind.

[wonderpug]

I found some great pictures illustrating the late apex concept:



This first image illustrates the difference between a plain geometric line around the turn and a standard symetrical racing line.



Here we see the advantage of a late apex.  You have to slow down more to make the sharper turn-in, but this line flattens out a lot sooner letting you get on the gas sooner, providing a faster exit time.  Your moment of slowness in the turn entry will more than be made up for by the speed advantage going into in the straight after the turn, as per the math & physics example I posted earlier.

I tend to think that a late apex is preferable for most turns even if you're not trying to pass someone as gellar mentioned, but especially in turns that are followed by a long straight.

[Harkonis]

do you have any pictures for hairpin, or decreasing radius turns? Or that godawful first turn at Tsuskunakgugkaga?

[Geezer]

I found some great pictures illustrating the late apex concept:



This first image illustrates the difference between a plain geometric line around the turn and a standard symetrical racing line.



Here we see the advantage of a late apex.  You have to slow down more to make the sharper turn-in, but this line flattens out a lot sooner letting you get on the gas sooner, providing a faster exit time.  Your moment of slowness in the turn entry will more than be made up for by the speed advantage going into in the straight after the turn, as per the math & physics example I posted earlier.

I tend to think that a late apex is preferable for most turns even if you're not trying to pass someone as gellar mentioned, but especially in turns that are followed by a long straight.

Those are good graphs.. Here's a little hint to help you know if you're hittingthe turns right..

If you apex too EARLY (i.e you turn in too soon) you will run out of track and fly off the outside of the  track.  If you apex too late you'll have plenty of track left between you and the left side of the car (in a right hand turn) or the right side of the car (in a left turn).

The ideal line will have you touching the outside of the track on entry and exit, and the inside of the track at the correct apex.  If you don't do all three of those you've blown the line.  If you go off you likely apexed too early. If you stay right in the middle of the track you apexed too late and you gave up lots of speed.

[Geezer]

Whats the Fix [to understeer]??

Gellar posted a list with a bunch of over/understeer corrections.  To reduce understeer, soften front shocks/stiffen rear shocks, lower front end/raise rear end, soften front sway bar/stiffen rear, raise front tire pressure/lower rear, or simply drive differently and take a different line.

'cept the bolded part is backwards   (within reason of course - taking pressure down to a point where the tire can't hold shape is counterproductive)

Higher pressures increase transitional responsiveness, but lower ultimate grip.

Generally the first thing I do to any car in Forza (so far) is knock the pressures down 2-4 psi front and back altering the ratio depending on whether the car is fwd or rwd.  The only exception (so far) is the elise/exige which I knock down to 24f/26 rear. 

[wonderpug]

Whats the Fix [to understeer]??

To reduce understeer, raise front tire pressure/lower rear

'cept the bolded part is backwards

Woops, fixed it above.

[gellar]

do you have any pictures for hairpin, or decreasing radius turns? Or that godawful first turn at Tsuskunakgugkaga?

I really hate that track.  It's my least favorite in the game.  It's just not any fun.

gellar

[Geezer]

do you have any pictures for hairpin, or decreasing radius turns? Or that godawful first turn at Tsuskunakgugkaga?

If noone has any, I'll create some when I get back from my trip Friday. Basically a decreasing radius turn calls for a late apex, and it one of those things where you wait to turn in, then wait till you think it's time, then wait a little more.

No idea what the first turn at Tsuskunakgugkaga is like from memory though

[EngineNo9]

If you have the manual all of the turn types are diagramed in there.  If you don't have the manual, IkeV linked to it in the other Forza 2 thread (although I can't get the link to work right now). 

[JuniorDan]

You always want to make the smoothest arc possible from the outside of the turn, to the inside at the apex, then back to the outside on the exit. You keep your maximum velocity this way and minimise the chance of spiking your lateral Gs and swaping ends.

Edit:

Juniordan, that's alot of power for that handling rating. I haven't found a track other than the Nissan Raceway that could use that kinda top end. I would tune that beast down and work on getting it to handle better...then start bumping the power up bit by bit, until it's just on the edge.

Also...found this that gives a brief description of the racing line.

This my good sir worked like a charm I am topping out at 218mph at 821hp and 781trq.  big decrease but the car is drivable, Thanks.
Next issue: The tires get war when they are green and traction is all good, So why on lap 6of 8 every time any car, they seems to loose their controllability on corners or slight turns? My first suspect was the tires however  they stay green I would expect them to be red if there was an issue, am I wrong for this?   

[EngineNo9]

I tend to get that same sort of problem, juniordan.  About 2/3 of the way through a race my tires just start to get all slippery even though they are still green.  It's like they are stickier before they get warmed up and then it all goes to hell.  It really annoys me when I've been running really well in first and then fall back several places just before the end of a race because my handling is shot.

[wonderpug]

Weird, I don't think I've noticed any reduced handling on the last laps of an 8+ lap race.  Are you guys using upgraded tires?  I don't think I've had the high end racing slicks on any of the cars I've raced 8+ laps with, but I would think that even those would last much longer than 6 laps.