Thursday, July 30, 2009
Andrew's banana
Met up with andrew recently to have a photoshoot for his silver bana, the shoot was suppose to be at the top of touge route but due to some minor mishaps, the shoot was done at caltex.
Sunday, July 26, 2009
track day pics
These are the pictures of me and my car during track day. they are taken from ray's blog. Im still busy so i have no time to edit my pictures, for the meanwhile enjoy pictures from ray
Thursday, July 23, 2009
Friday, July 17, 2009
Wednesday, July 15, 2009
Stuff for sale
I have a set of cusco rollcage for sale.original cusco and its for evo 1,2,3 and wira. and I also have a set of Evo bodypart for sale. kindly contact me for more details.
Being inside a cage
It was bright sunny day and my friend alan was back in town, he was back for the holidays and he brought back my stuff for me. I met up with him andwe headed down my workshop for some DIY .took me the whole day to fix it but it was worth it, what is it ? it relates to the title,hah.Ill let the pictures do the talking.
My current look, I think i havent posted the current looks of my cars for years
I love pillars. xD
Feel's like im in a cage
The command centre
Hope to try the effects of it soon ! but been driving on the road for a day and it feels hard.
My current look, I think i havent posted the current looks of my cars for years
I love pillars. xD
Feel's like im in a cage
The command centre
Hope to try the effects of it soon ! but been driving on the road for a day and it feels hard.
Wednesday, July 8, 2009
handling setup
Found this on the internet when searching on how to improve my car's handling..found this useful so i decided to share it with everyone.Taken from wikipedia
Car handling and vehicle handling is a description of the way wheeled vehicles perform transverse to their direction of motion, particularly during cornering and swerving. It also includes their stability when moving in a straight line. Handling and braking are the major components of a vehicle's "active" safety. The maximum lateral acceleration is sometimes discussed separately as "road holding". Handling is an esoteric performance area because rapid and violent manoeuvres are often only used in unforeseen circumstances. (This discussion is directed at road vehicles with at least three wheels, but some of it may apply to other ground vehicles.)
Cars that drive on public roads, whose engineering requirements emphasize handling above passenger space and comfort, are called sports cars.
Factors that affect a car's handling
Weight distribution
Center of gravity height
The center of gravity height, relative to the track, determines load transfer, (related to, but not exactly weight transfer), from side to side and causes body lean. Centrifugal force acts at the center of gravity to lean the car toward the outside of the curve, increasing downward force on the outside tires.
Height of the center of gravity relative to the wheelbase determines load transfer between front and rear. The car's momentum acts at its center of gravity to tilt the car forward or backward, respectively during braking and acceleration. Since it is only the downward force that changes and not the location of the center of gravity, the effect on over/under steer is opposite to that of an actual change in the center of gravity. When a car is braking, the downward load on the front tires increases and that on the rear decreases, with corresponding change in their ability to take sideways load, causing oversteer.
Lower center of gravity is the principal performance advantage of sports cars, compared to sedans and (especially) SUVs. Some cars have light materials in their roofs, partly for this reason. It is also part of the reason that traditional sports cars are open or convertible.
Body lean can also be controlled by the springs, anti-roll bars or the roll center heights.
Center of gravity forward or back
In steady-state cornering, because of the center of gravity, front-heavy cars tend to understeer and rear-heavy cars to oversteer, all other things being equal. The mid-engine design offers the ideal center of gravity.[citation needed]
When all four wheels and tires are of equal size, as is most often the case with passenger cars, a weight distribution close to "50/50" (i.e. the center of mass is mid-way between the front and rear axles) produces the preferred handling compromise.
The rearward weight bias preferred by sports and racing cars results from handling effects during the transition from straight-ahead to cornering. During corner entry the front tires, in addition to generating part of the lateral force required to accelerate the car's center of mass into the turn, also generate a torque about the car's vertical axis that starts the car rotating into the turn. However, the lateral force being generated by the rear tires is acting in the opposite torsional sense, trying to rotate the car out of the turn. For this reason, a car with "50/50" weight distribution will understeer on initial corner entry. To avoid this problem, sports and racing cars often have a more rearward weight distribution. In the case of pure racing cars, this is typically between "40/60" and "35/65." This gives the front tires an advantage in overcoming the car's moment of inertia (yaw angular inertia), thus reducing corner-entry understeer.
Using wheels and tires of different sizes (proportional to the weight carried by each end) is a lever automakers can use to fine tune the resulting over/understeer characteristics.
Roll angular inertia
This increases the time it takes to settle down and follow the steering. It depends on the (square of the) height and width, and (for a uniform mass distribution) can be approximately calculated by the equation: I = M(height2 + width2) / 12.
Greater width, then, though it counteracts center of gravity height, hurts handling by increasing angular inertia. Some high performance cars have light materials in their fenders and roofs partly for this reason.
Yaw and pitch angular inertia (polar moment)
Unless the vehicle is very short, compared to its height or width, these are about equal. Angular inertia determines the rotational inertia of an object for a given rate of rotation. The yaw angular inertia tends to keep the direction the car is pointing changing at a constant rate. This makes it slower to swerve or go into a tight curve, and it also makes it slower to turn straight again. The pitch angular inertia detracts from the ability of the suspension to keep front and back tire loadings constant on uneven surfaces and therefore contributes to bump steer. Angular inertia is an integral over the square of the distance from the center of gravity, so it favors small cars even though the lever arms (wheelbase and track) also increase with scale. (Since cars have reasonable symmetrical shapes, the off-diagonal terms of the angular inertia tensor can usually be ignored.) Mass near the ends of a car can be avoided, without re-designing it to be shorter, by the use of light materials for bumpers and fenders or by deleting them entirely.
Suspension
Automobile suspensions have many variable characteristics, which are generally different in the front and rear and all of which affect handling. Some of these are: spring rate, damping, straight ahead camber angle, camber change with wheel travel, roll center height and the flexibility and vibration modes of the suspension elements. Suspension also affects unsprung weight.
Many cars have suspension that connects the wheels on the two sides, either by a sway bar and/or by a solid axle. The Citroën 2CV has interaction between the front and rear suspension.
The flexing of the frame interacts with the suspension. (See below.)
Suspension travel
The severe handling vice of the TR3 and related cars was caused by running out of suspension travel. (See below.) Other vehicles will run out of suspension travel with some combination of bumps and turns, with similarly catastrophic effect. Excessively modified cars also may encounter this problem.
Tires and wheels
In general, larger tires, softer rubber, higher hysteresis rubber and stiffer cord configurations increase road holding and improve handling. On most types of poor surfaces, large diameter wheels perform better than lower wider wheels. The fact that larger tires, relative to weight, stick better is the main reason that front heavy cars tend to understeer and rear heavy to oversteer. The depth of tread remaining greatly affects aquaplaning (riding over deep water without reaching the road surface). Increasing tire pressures reduces their slip angle, but (for given road conditions and loading) there is an optimum pressure for road holding.
[edit] Track and wheelbase
The track provides the resistance to sideways weight transfer and body lean. The wheelbase provides resistance to front/back weight transfer and to pitch angular inertia, and provides the torque lever arm to rotate the car when swerving. The wheelbase, however, is less important than angular inertia (polar moment) to the vehicle's ability to swerve quickly.
Car handling and vehicle handling is a description of the way wheeled vehicles perform transverse to their direction of motion, particularly during cornering and swerving. It also includes their stability when moving in a straight line. Handling and braking are the major components of a vehicle's "active" safety. The maximum lateral acceleration is sometimes discussed separately as "road holding". Handling is an esoteric performance area because rapid and violent manoeuvres are often only used in unforeseen circumstances. (This discussion is directed at road vehicles with at least three wheels, but some of it may apply to other ground vehicles.)
Cars that drive on public roads, whose engineering requirements emphasize handling above passenger space and comfort, are called sports cars.
Factors that affect a car's handling
Weight distribution
Center of gravity height
The center of gravity height, relative to the track, determines load transfer, (related to, but not exactly weight transfer), from side to side and causes body lean. Centrifugal force acts at the center of gravity to lean the car toward the outside of the curve, increasing downward force on the outside tires.
Height of the center of gravity relative to the wheelbase determines load transfer between front and rear. The car's momentum acts at its center of gravity to tilt the car forward or backward, respectively during braking and acceleration. Since it is only the downward force that changes and not the location of the center of gravity, the effect on over/under steer is opposite to that of an actual change in the center of gravity. When a car is braking, the downward load on the front tires increases and that on the rear decreases, with corresponding change in their ability to take sideways load, causing oversteer.
Lower center of gravity is the principal performance advantage of sports cars, compared to sedans and (especially) SUVs. Some cars have light materials in their roofs, partly for this reason. It is also part of the reason that traditional sports cars are open or convertible.
Body lean can also be controlled by the springs, anti-roll bars or the roll center heights.
Center of gravity forward or back
In steady-state cornering, because of the center of gravity, front-heavy cars tend to understeer and rear-heavy cars to oversteer, all other things being equal. The mid-engine design offers the ideal center of gravity.[citation needed]
When all four wheels and tires are of equal size, as is most often the case with passenger cars, a weight distribution close to "50/50" (i.e. the center of mass is mid-way between the front and rear axles) produces the preferred handling compromise.
The rearward weight bias preferred by sports and racing cars results from handling effects during the transition from straight-ahead to cornering. During corner entry the front tires, in addition to generating part of the lateral force required to accelerate the car's center of mass into the turn, also generate a torque about the car's vertical axis that starts the car rotating into the turn. However, the lateral force being generated by the rear tires is acting in the opposite torsional sense, trying to rotate the car out of the turn. For this reason, a car with "50/50" weight distribution will understeer on initial corner entry. To avoid this problem, sports and racing cars often have a more rearward weight distribution. In the case of pure racing cars, this is typically between "40/60" and "35/65." This gives the front tires an advantage in overcoming the car's moment of inertia (yaw angular inertia), thus reducing corner-entry understeer.
Using wheels and tires of different sizes (proportional to the weight carried by each end) is a lever automakers can use to fine tune the resulting over/understeer characteristics.
Roll angular inertia
This increases the time it takes to settle down and follow the steering. It depends on the (square of the) height and width, and (for a uniform mass distribution) can be approximately calculated by the equation: I = M(height2 + width2) / 12.
Greater width, then, though it counteracts center of gravity height, hurts handling by increasing angular inertia. Some high performance cars have light materials in their fenders and roofs partly for this reason.
Yaw and pitch angular inertia (polar moment)
Unless the vehicle is very short, compared to its height or width, these are about equal. Angular inertia determines the rotational inertia of an object for a given rate of rotation. The yaw angular inertia tends to keep the direction the car is pointing changing at a constant rate. This makes it slower to swerve or go into a tight curve, and it also makes it slower to turn straight again. The pitch angular inertia detracts from the ability of the suspension to keep front and back tire loadings constant on uneven surfaces and therefore contributes to bump steer. Angular inertia is an integral over the square of the distance from the center of gravity, so it favors small cars even though the lever arms (wheelbase and track) also increase with scale. (Since cars have reasonable symmetrical shapes, the off-diagonal terms of the angular inertia tensor can usually be ignored.) Mass near the ends of a car can be avoided, without re-designing it to be shorter, by the use of light materials for bumpers and fenders or by deleting them entirely.
Suspension
Automobile suspensions have many variable characteristics, which are generally different in the front and rear and all of which affect handling. Some of these are: spring rate, damping, straight ahead camber angle, camber change with wheel travel, roll center height and the flexibility and vibration modes of the suspension elements. Suspension also affects unsprung weight.
Many cars have suspension that connects the wheels on the two sides, either by a sway bar and/or by a solid axle. The Citroën 2CV has interaction between the front and rear suspension.
The flexing of the frame interacts with the suspension. (See below.)
Suspension travel
The severe handling vice of the TR3 and related cars was caused by running out of suspension travel. (See below.) Other vehicles will run out of suspension travel with some combination of bumps and turns, with similarly catastrophic effect. Excessively modified cars also may encounter this problem.
Tires and wheels
In general, larger tires, softer rubber, higher hysteresis rubber and stiffer cord configurations increase road holding and improve handling. On most types of poor surfaces, large diameter wheels perform better than lower wider wheels. The fact that larger tires, relative to weight, stick better is the main reason that front heavy cars tend to understeer and rear heavy to oversteer. The depth of tread remaining greatly affects aquaplaning (riding over deep water without reaching the road surface). Increasing tire pressures reduces their slip angle, but (for given road conditions and loading) there is an optimum pressure for road holding.
[edit] Track and wheelbase
The track provides the resistance to sideways weight transfer and body lean. The wheelbase provides resistance to front/back weight transfer and to pitch angular inertia, and provides the torque lever arm to rotate the car when swerving. The wheelbase, however, is less important than angular inertia (polar moment) to the vehicle's ability to swerve quickly.
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