Bit Of Love Peoples ..... !

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Bit Of Love Peoples ..... !

Post  FTA Damo on Tue Jul 27, 2010 12:32 pm

Just showing bit of love and few things for you guys to think on Smile enjoy

I will update on things ive missed , SO STICKY THIS MFO
this aint a 5 min read so make sure u got some time , try to just focus on one thing at a time , cuz this is alot to take in ....... here goes



Tires.

Note from Time: Peak Grip Temperature is between 180 and 210 degrees

This is a Master's Class Tuning and you need to use the telemetry for this.

Start by picking any track and test run 3 laps in test drive mode, now bring up the heat and tires misc. telemetry and observe the temperature & pressure.

Tires reach peak friction at 32 psi; however as long as you're running a race psi of 30-34 degrees, you're still in good grip range. Race psi and race temperature is measured after a few laps when your tires have heated up and reached their performance levels.

Tire Temp - Cause - Recommended Adjustment

Center hotter than edges - Tire pressure too high - Reduce 1 psi for each 5 deg F difference

*****
* ** *
* ** *
* ** *
*****

Edges hotter than center - Tire pressure too low - Add 1 psi for each 5 deg F difference

*****
* ** *
* ** *
* ** *
*****


Inner edge hotter than outer edge - Too much negative camber - Decrease negative camber

*****
* ** *
* ** *
* ** *
*****


Outer edge hotter than inner edge - Not enough negative camber or too much toe-in - Increase negative camber or decrease toe-in

*****
* ** *
* ** *
* ** *
*****


Tire below peak temperature range - Tire pressure too high, tire too wide or springs/sway bars too soft at that axle - Decrease tire pressure. reduce tire width or stiffen up springs and sway bars on that axle

Tires above peak temperature range - Tire pressure too low, tire too narrow, or springs/sway bars too stiff at that axle - Increase tire pressure, increase tire width or soften up springs and sway bars on that axle

Front tires hotter than rear - Car is under steering. Too much front spring/sway bar, not enough rear spring/sway bar, front pressure too high, front tires too narrow, rear tires too wide - Soften up front spring and sway bar, stiffen up rear spring and sway bar, increase front pressure or decrease rear pressure

Rear tires hotter than front - Car is over steering. Too much rear spring/sway bar, not enough front spring/sway bar, front pressure too high, rear pressure too low, rear tires too narrow, front tires too wide - Soften up rear spring and sway bar, stiffen up front spring and sway bar, increase rear pressure or decrease front pressure


I hope you use the telemetry to adjust this setting based on your driving. This is the correct way to set it, so the next time some dude tell you 28/28 or 29/28 ask him how he came to that conclusion ...just make that you did the 3 laps to see if the pressure reached its peak which is 32...

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Alignment.


Handling characteristics are usually defined by over steering and under steering.

Over steering is fish tailing, when the back end comes out. good for drift bad for race pace.
Under steering is when the car experiences little or no steering when your trying to to turn left or right.


Camber, Toe and Caster

The three major alignment parameters on a car are toe, camber, and caster.Most enthusiasts have a good understanding of what these settings are and what they involve, but many may not know why a particular setting is called for, or how it affects performance. Let's take a quick look at this basic aspect of suspension tuning.

Once you understand the terminology you can move into the adjustment stage.


What is Toe?

My simplest analogy is made to pigeons and ducks. Most people's feet point straight ahead. Compared that to a pigeon or duck there is a significant difference. In some people, however, the feet point inward.This is called in toeing (say "in-toe-ing"), or "pigeon feet." If your Charlie Chaplin then I'm sure you've seen his duck walk with his toes pointing outward.

Top down view of a tire in pairs

Toe - Straight (0 degrees)

/ \ **** ****
| **** ****
| **** ****
| **** ****
| **** ****

Toe - In (Positive Degrees)

/ **** ****
/ **** ****
/ **** ****
/ **** ****
/ **** ****

Toe - Out (Negative Degrees]

\ **** ****
\ **** ****
\ **** ****
\ **** ****
\ **** ****

The amount of toe can be expressed in degrees as the angle to which the wheels are out of parallel

Toe settings affect three major areas of performance:



Tire Wear
For minimum tire wear and power loss, the wheels on a given axle of a car should point directly ahead when the car is running in a straight line. Excessive toe-in or toe-out causes the tires to scrub, since they are always rotating relative to the direction of travel.


Too much toe-in causes accelerated wear at the outboard edges of the tires
Too much toe-out causes wear at the inboard edges.



Straight-line Stability
So if minimum tire wear and power loss are achieved with zero toe, why have any toe angles at all?
is that toe settings have a major impact on directional stability. With the steering wheel centered, toe-in causes the wheels to tend to roll along paths that intersect each other. Under this condition, the wheels are at odds with each other, and no turn results.Even with slight steering input the rolling paths of the wheels still don't make a turn. In this way, toe-in enhances straight-line stability.


Corner Entry Only
If the car is set up with toe-out on the front tires any minute steering angle beyond the perfectly centered position will cause the inner wheel to steer in a tighter turn radius than the outer wheel. Thus, the car will always be trying to enter a turn, rather than maintaining a straight line of travel. So it's clear that toe-out encourages the initiation of a turn, while toe-in discourages it





What is Camber?
Have you seen the stance of a skier, usually their knees are closer than the feet. This stance is said to be a camber effect. Imagine running on a200m oval track. When on the corner, you feel to get better track traction you need to make your outer feet is touch the inner side of your feet. Camber is the inward or outward tilt of the wheel when viewing from the front or rear of the car. Camber is probably the most useful and popular alignment adjustment that can be made to a streetcar.

Maximum cornering force is achieved when the camber of the outside wheels relative to the ground is about -0.5 degrees. A slight negative camber in a turn maximizes the tire contact patch due to the way the tire deforms under lateral load. Hence, it is good to have some negative camber to increase cornering force.



View from the front of a car

Camber - Straight (0 degrees)

**** ****
**** ****
**** ****
**** ****
**** ****

Camber - (Negative Degrees)

/ **** ****
/ **** ****
/ **** ****
/ **** ****
/ **** ****

Camber - Out (Positive Degrees]

\ **** ****
\ **** ****
\ **** ****
\ **** ****
\ **** ****

The best way to determine the proper camber for competition is to measure the temperature profile across the tire tread immediately after completing some hot laps. In general, it's desirable to have the inboard edge of the tire slightly hotter than the outboard edge.



What is Caster?
This is probably the hardest to explain. The technical description is the angle to which the steering pivot axis is tilted forward or rearward from vertical, as viewed from the side. Lost? Don't worry I bring it back with some diagrams. Picture a Harley with a long nose or fork.This a positive caster setting that is very high. Makes it good to go straight mostly, but the mini will beat it at turning radius.

Ina car you have ball joints connected to your wheels. These keep the wheels attached to the car. Also you have a steering column attached to the ball joint. The angle between the joint and the steering is the caster angle.

Say you driving down the straight on the hwy and you need to get your hands of the wheel. Notice how easily the car continues to go straight when you let your hands off. This is because of caster in the wheel. Anything attached to a wheel has caster. With caster you have a positive and negative setting. In Forza its represented by low and high. Forza doesn't have a negative caster because cars are not designed the same way the casters are in shopping carts.


Positive Caster which provides good directional control but harder top speed cornering.
Negative Caster does not provide good directional control stability but easier low speed cornering.

Top Down View of a car


******
****** () <- Lower Ball Joint
******
****** () <- Upper Ball Joint
******

Side View of a car

********
*******(*)* () <- Lower Ball Joint
***********
****(*)**** () <- Upper Ball Joint
********

Low Caster (Positive) of a Car

********
*******(*)* () <- Lower Ball Joint
***********
******(*)* () <- Upper Ball Joint
*******



High Caster (Positive) of a Car


********
*******(*)* () <- Lower Ball Joint
***********
*(*)******* () <- Upper Ball Joint
********

Low Caster (Negative) of a shopping cart

********
**(*)****** () <- Upper Ball Joint
***********
*****(*)** () <- Upper Ball Joint
********


Notice the shopping cart. see how easy it becomes to turn at a low speed.Imagine 60 mph with that caster setup turning left of right would be dangerous.

So high caster is good but makes it hard to turn, low caster is bad make it hard to keep straight.

Now for fun part.

Tuning

Questions? What are you experiencing when you drive the car through turns. Over steer or Under steer?


Camber
Patience is the key because alignment tuning is the hardest in Forza.
Again you will need a telemetry for this. Stop the car completely on a flat track with no elevation. Launch Telemetry and go to Tires. Note the camber angle the car makes with the road. If it matches the setting you have tuned then you are on flat surface.

Restart tuning and race for a couple of hot laps. Usually 3 is good enough. Don't worry about red penalty. Stop after 3 and watch the replay. During there play launch the telemetry and jump to the "Tires Misc".

you need to watch the replay at least 2 times to get this down.

Start by looking at the camber angle on the front wheels.
Note how many times you see a positive number.
Repeat for the rear tires on the 2nd replay.

Now go back to tuning and change the following if applicable

Positive camber on straights - Decrease camber by .1
Positive camber on turns - Decrease camber by .1

No Positive camber on straights - Increase camber by .1
No Positive camber on turns - Increase camber by .1

Whats the point? Positive camber is the enemy and reduces traction and stability.

Tuning for Cornering.

For Left Turn
The Left Tire must be less than or equal to 0.0 degrees.

For Right Turn
The Right Tire must be less than or equal to 0.0 degrees.

Closer to 0 better the handling. Anything above 0 means that the tire is not helping you.

Toe

General Rule of Thumb Is to Improve the car for corner entry.

Combination's include


Front Toe + Rear Toe 0 <- Better Corner Entry Any Car
Front Toe - Rear Toe 0 <- Reduce Steer Sensitivity Bad Corner Entry

Front Toe 0 Rear Toe + <- Under steer tendencies but Better Corner Exit in any Car and stability under braking.
Front Toe 0 Rear Toe - <- Slow Corner Exit

Front Toe + Rear Toe + <- Provides stability under braking and creates over steer tendencies in cornering.
Front Toe + Rear Toe - <- Amazing Handling on any car but can cause understeer

Front Toe - Rear Toe + <- Amazing Handling on any car but can cause oversteer
Front Toe - Rear Toe - <- Oval track


Examples
Any Car for Better Turn In Response
Front Toe Out : .1 (duck feet ready for turning left or right)

\ **** ****
\ **** ****
\ **** ****
\ **** ****
\ **** ****

/ \ **** ****
| **** ****
| **** ****
| **** ****
| **** ****




Cars with massive power and no handling.
Front: 0
Rear Toe In: -.1 (pigeon feet, ready to face the direction of turn on acceleration)


/ \ **** ****
| **** ****
| **** ****
| **** ****
| **** ****


/ **** ****
/ **** ****
/ **** ****
/ **** ****
/ **** ****

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Brakes.

What is Brake Bias?

Brake bias is the balance of braking power between the front and rear brakes.It is usually represented as a percentage. For example, a brake bias of65/35 means that the front brakes get 65% of the braking power, and the rear brakes get 35% of the braking power.

Why do I need to know?
Brake bias controls the way that the car handles when the brakes are applied.Therefore, it is useful in changing the corner entry handling characteristics of a car if braking is necessary going into a corner.

What happens on adjustment?
Moving the brake bias toward the front brakes makes the car tighter and more stable while braking and entering a turn. Moving the brake bias toward the rear makes the car looser while braking and entering a turn.Excessive front braking power can lock up the front tires and decrease the overall effectiveness of your brakes since you are not using the rear tires to slow down the car.

Rule of Thumb
The front brakes should always have more braking power than the rear because the weight transfer during braking loads the front tires an dun loads the rear tires. If you have too much rear brake, the rear tires will lock as weight transfers forward and makes the rear of the car lighter. However, make sure you do not have too much front brake either.

How To Tune Brakes?
Asa starting point "TURN ABS OFF", try setting your brake bias between70/30 and 80/20. Fine-tune the car from there. I found that the Optimal Setting is 47% Front. I will get into the pressure later.

As Usual Replay Your Runs and Bring Up Telemetry and go to Friction.
Reading the Telemetry for Friction is as follows.

Red Circles is a visual of the grip available at each tire, and the blue lines inside them are the amount of grip you are actually asking the tire to produce. This displays a more detailed brake down of the "Friction Circle" type telemetry from the "Body Acceleration" telemetry screen.If you watch the red circles off the start line, the front ones will get slightly smaller and the back ones will grow. That is because a tire's grip is related to the amount of weight on that tire... more weight = more grip, to an extent. So as you jump on the gas, weight shifts backward, and the rear circles grow because your rear tires have more grip. When you go into a corner, you will also see the circles change size as weight shifts side-to-side. jump over a curb, and the circles disappear if the tire leaves the ground! The blue line shows how much you are asking of the tire - if it is outside the red circle, it means you are pushing that tire too hard and it has lost grip, so it is sliding. If you look at the telemetry during a spin, the blue lines will be well outside the red circles. If the blue line is inside the circle, it means that there is more grip available, since the circle is the limit. You are using your tires most effectively when the blue line is touching the red circle.

Notice while Braking which circles are getting bigger, usually the front will get bigger than the rear with the bias > that 50% Front. Keep moving 1% Front till you have lost grip completely skidded out as a result of understeer when braking. Move back 1% to be in the safe zone.

Tuning Brake Pressure
Also look at the brake indicator (vertical red line on the left of the telemetry) notice if you are completely at 100% or just 70%. This will simply your braking input sensitivity on the controller. Once you have found the optimal setting for your brake bias. Brake pressure will improve your stopping.

Based On Braking Style You Maybe Doing 1 of the following:

1. On Demand (Pull the trigger all the way back)

2. On Power (Pull the trigger all the way back with acceleration)

3. Off Throttle Down Shift Half Brake (Pull the trigger half way)


With ABS OFF (ABS ON counters your braking, meaning more the light is on the more your travelling forward)

1.On Demand: Try going for a less brake pressure, you want all the tires to skid only when the trigger is completely back. Try tuning so that you have a little play to create a skid and a good brake. Start at100% and keep going down 5% till you have that perfect brake. Using the Telemetry make sure you have 4 big red circles when skidding to indicate good brake bias.

2. On Power: Same as above but make sure you don't get into a race-brake situation where your locking the front and burning the rears tires..looks cool but can be costly.

3.Off Throttle: Brake sensitivity is the key. You use only 10~40% on sensitivity (i.e depressing the brake 1/2 to 1/4, you never completely hold the entire brake down during a race (unless you want to show off your ABS skills lol). You know how to lock brakes to your advantage.You use the gear down to your advantage ONLY AFTER you started braking.Typically you keep going up in pressure settings because feel you can stop at a dime.


I'm personally at 130~160% in most cars without ABS. Since the game came out I've been doing without ABS so now it comes a bit natural. Bottom line is if you can drive with TCS off you can do the same with ABS off. If you can gently squeezing the throttle coming out of a corner, you can gently squeeze the brakes.

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Gear Ratio.

Tuning Gear Ratios
Gearing is the key to better acceleration, braking, cornering and top speed.

There are endless debates on torque and horse power and we wont get into that here.You know this because most American/German cars make torque and Japanese make horsepower. But its important to understand the terminology.

The Formula

Torque X RPM
Horsepower = -----------------------
5252


Case for Torque
Any given car, in any given gear, will accelerate at a rate that *exactly*matches its torque curve (allowing for increased air and rolling resistance as speeds climb). Another way of saying this is that a car will accelerate hardest at its torque peak in any given gear, and will not accelerate as hard below that peak, or above it. Torque is the only thing that a driver feels, and horsepower is just sort of an esoteric measurement in that context. 300 foot pounds of torque will accelerate you just as hard at 2000 rpm as it would if you were making that same torque at 4000 rpm in the same gear, yet, per the formula, the horsepower would be *double* at 4000 rpm. Therefore, horsepower isn't particularly meaningful from a driver's perspective, and the two numbers only get friendly at 5252 rpm, where horsepower and torque always come out the same.

Case for Horsepower
OK.If torque is so all-fired important, why do we care about horsepower?Because, "It is better to make torque at high rpm than at low rpm,because you can take advantage of *gearing*.



Telemetry Tuning
Note you cars Peak Torque RPM and Peak Horsepower RPM.
Go to Test Drive in the Oval


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Differential.



Differential: Your differential controls how well your car is able to put down its power and torque to the road.A differential will send the power the wheels with the least amount grip,in normal,everday driving condition the power is sent to the wheels on the left aka outside wheels,when turning right,or the wheel which are not crossed out

/ /

I I

However in aggressive,racing condition,power is often sent to inside wheels,or the wheels on the right aka the inside wheels,when turning right,or the wheels which are not crossed out.It does this because due to weight transfer to the left side of the car,the inside wheels have the least amount of grip

/ /

I I

This causes the car to lose traction and wast power,which is why high performance cars usally have limited slip diffs.If the differential sends to much of the torque to the inside,or outside wheel or wheels,the limited slip kicks in,and locks the wheels together,although keep in mind that a limited slip diff evenly lock your wheels together,one wheel is still receiving more torque,but only slightly.

Acceration(accl)=The acceleration setting controls at what point the differential locks while on the gas.Having a higher % will prevent individual wheels from slipping,allowing you to use more of the power when exiting a corner,but in a rwd car,will make the car easier to spin out and drift.Having a lower % will make it easier for individual wheels to slip,causing you to waste more of the power when exiting a corner,but in a rwd car it will make the car hard to spin out and drift and if its too low then you will see a black patch coming from the inside wheel.Lower power cars usually can withstand a high rate.

I recommend using a higher slip rate,even in the front wheels,it usually creates a less sloppy feeling when you exist a corner and I find that it allows you to leave the corner with higher speeds.But if your back end slides out more then what you want it to,then it may be a good idea to lower the rate.

Deacceration(deaccl)= The deceleration setting controls at what point the differential locks when you let off the gas,usually when entering a corner.The high the rate the more stable your car will be,reducing oversteer and create a "on rails" feeling,but it will make your car less agile and can cause understeer.Also if you do oversteer, while accelerating, having a higher rating can make it harder to correct the skid.

I recommend using a lower slip,which will make will make your car more agile,but if your car tends to oversteer,or feels unstable,it may be a good idea to increase the slip rate.

Center:The center differential controls the how the torque is divided between the front and back wheels in an AWD car.Like any other differential it sends more power to wherever their is the least amount of grip.By setting a rear biased rate your making it easier for the power to be sent to the rear wheels.But the rate still changes biased where the most amount of grip is and will still try to send more power to the front wheels if they have less grip.

I recommend a slightly rear bias, of around 60-75%,to get the most performance out of your AWD system

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-Damping:

Controls the suspension's stiffness and compression between wheel and the wheel-well. Both Rebound and Bump work in "reverse-way", for example having the Front Rebound higher than rear increases grip on the rear, because more weight is concentrated in the front tires under spring compression, so rear wheels can work more freely.



Rebound Stiffness:


Increasing Front Rebound - More grip in the rear (weight shift blah blah etc.)
Decreasing Front Rebound - Reduces transitional understeer

Increasing Rear Rebound - More grip in the front
Decreasing Rear Rebound - Reduces transitional oversteer


Front biased Rebound - Increases understeer & increases grip in RWD cars, sacrificing turn-in slightly
Rear biased Rebound - Increases oversteer & highly recommended for FWD & AWD cars.
(The bigger the balance difference, the bigger the effect - bigger than 3.0 differences not encouraged)


You cant really have excessively high Rebound setups, it all depends what the Bump stiffnesses are set to. If you are using high Rebound (9.0+) with low Bump (<4.0) your car may become upset by curbs and such, this is also modified by ride height and suspension stiffnesses. Higher Rebound than Bump is a must. The Bump stiffness should be 75% of the Rebound's stiffness at maximum.Although the in-game Damping description says ~50% of the Rebound's stiffness should be minimum, it really doesnt have to be. Low bump stiffness works great.



Bump Stiffness:


Increasing Front Bump - Increases understeer and slightly increases rear grip + modifies the effectiveness of Damping and Spring setups
Increasing Rear Bump - Increases oversteer and slightly increases front grip + modifies the effectiveness of Damping and Spring setups


Decreasing Front Bump - Improves bump absorption + modifies the effectiveness of Damping & Springs
Decreasing Rear Bump - Improves bump absorption + modifies the effectiveness of Damping & Springs


Front biased Bump - Increases understeer + slightly increases grip in RWD cars
Rear biased Bump - Increases oversteer & highly recommended for FWD & AWD cars.
(The bigger the balance difference, the bigger the effect - bigger than 2.0 differences not encouraged)



You will know when your Bump stiffness is excessively high. The chassis feels like it floats on the tires and you feel unconnected to the road. A good, practical way to test out your bump stiffness if you dont want understand all the mumbogumbo, is to take a mild curb aggressively and then seeing if the car rolls. (Dont try Sebring or Maple curbs, they'll roll you no matter what). If it rolls, your setup is too stiff, if you already had your bump at <3.5 then the problem is in your ride height or rebound. Bump stiffness can always be kept relatively low. (I personally never use 5.0+ bump stiffness). Bump stiffness in general fine-tunes the Damping & Suspension.



Tune the springs & ride height before going over to damping.



Also; Rear-biased Damping works for RWD cars well too, front-biased is just one of the several ways to increase grip on some RWD cars, not necessarily on all of them.

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The upgrading part!


Engine and Power

Air Filter - Helps maintain cooler intake temperatures, and Helps the engine breathe more freely.
Fuel System - More efficient fuel flow, Extracts more power form the fuel.
Ignition - Also helps burn fuel efficiently will producing more power.

Exhaust - Lets the engine exhale more freely which creates more power.
Camshaft - Helps engine breathe more freely and able to rev to higher rpm producing more power and torque.
Valves - Lets your engine breathe freely, and lets you have higher RPM range.
Displacement - Makes the engine more durable.
Pistons and Compression - Tolerates more heat resistant pistons and modifications to optimize for improved power.
Twin Turbo - Uses exhaust gas to produce more power.
Intercooler - Cools the hot intake air from a turbocharger or supercharger before it is forced into the engine. Helps pack more energy per stroke.

Flywheel - Lighter weight flywheel's allow the engine to respond to the throttle more quickly and increase RPM faster. Providing better acceleration.
Platform and Handling

Brakes - Use the proper brakes (Stock-Race) depending on how much Horsepower you have.
Springs and Dampers - Helps with weight transfer and speed/stability through corners.
Anti-roll bars - Extra stability. So if you are getting understeer add Front roll bars. And if you are getting over steer add rear roll bars.
Chassis Reinforcement and Roll Cage - Besides keeping the driver safe it allows your suspension to work to its full potential.
Weight reduction - Different reductions take away different things to help the car corner better and faster.
Drivetrain

Clutch - The better the clutch the more torque the engine can handle with out damaging it.
Transmission - The better the transmission the more power it can transmit from the engine to the wheels. Also making shifts quicker and more efficient.
Driveline - Improves throttle response and acceleration.
Differential - Allows the tire on each side to at different rates. Inside tire always travels a shorter distance.
Tires and Rims

Tire compound - The better the compound you use the more grip you will get but the less life in the tires you will have.
Tire width - The more rubber is on the road. RWD - Rear tires always wider than front. FWD - Front tires always wider. AWD - Rear would be a better idea to have wider.
Rim size - Bigger rims are less prone to deforming. It increases Acceleration and cornering forces. But Increases car weight.
Rim Style - Improves looks and handling while decreasing weight and rotational inertia.
Aero and Appearance

Front bumper - Increases load over the front wheels adding downforce. Does not take effect until 65MPH.
Rear Wing - Increases load over the rear tires adding downforce. Does not take effect until 65MPH.
Rear bumper - Has the Potential to decrease lift at high speeds.
Side skirts - increases top speed by reducing drag. Due to the weight though if can reduced acceleration and braking.
Hood - With a lighter hood it can adjust weight distribution for improved performance.
Conversions - This applies to everything in this category.

If you swap anything in this category remember that is has a different upgrade path so it may look like you will get more power and weight loss. but it could mean you are losing power and weight. So be careful


Thanx For Reading .......... FTA Damo , "Peace Out"
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FTA Damo

Posts : 6
Join date : 2010-07-20
Age : 28
Location : In Da Jungle Wid Da Sticky Plants ;)

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