Well what and how do i start this one. the trouble with me is i just wanner play, but shouldnt yet. let me explain. at the moment im still trying to learn to drive the zed again and i should wait tell the proper weather/ dry days but hey ho. if i launch my car and do it in a sensable manner from a straght line then the car feels a bit too light at the front almost like the steering too light and bouncy and im trying to get the feel for the car. i dont mind the rear end of the car comming out if you can get intune with the balance with your cars handling. im not talking serious drop the clutch launches yet or nothing like that. im quite happy getting the rear out a little out of junctions when theres no blody traffic ilands near the said junction.im trying to get a balence saff fill that if and when i put my foot down the front dont seem to planted if you know what i mean. and so far ive not had a dry road day in the week ive been home rubish.

ealyer i was readding this so you sort of get what i mean.

Anti-Squat

Anti-squat is the exact same geometry applied at the back axle of a rear-wheel-drive car. Unlike the front of the car, small amounts of anti-squat are generally a good thing for a rear-drive car since it allows for softer rear suspensions without the excess squat.

 

Cars like the Nissan R32 Skyline GT-R, Z32 300ZX and S13 240SX have a great deal of anti-squat in their rear suspension geometry. This makes them transition. To on-throttle over steer very rapidly because anti-squat, like anti-dive, significantly increases the wheel rate. This is why the S13 works so well for drifting.

 

Extreme anti-squat can cause wheel spin and rear wheel hop under power, which is why the Z32 is notorious for launching poorly at the drag strip. Rear-wheel-drive drag racers have made a science of anti-squat tuning to maximize rear-wheel traction. Drag cars often have so much anti-squat geometry that the back of the car actually lift when launching, driving the tires into the ground. Drag cars have adjustable four-link rear suspensions, so this percentage is tuneable for the amount of bite desired in different conditions

Maybe when i get the NA rear end put on my car this spring im thinking i should buy some stiffer shocks maybe

the cars a man tt and the setup is all standerd for a ttuk man , and its setting on toyo proxes all round and 235 40 18 at frount and 275 35 18 on rear.

what say u.

Interesting mate, I've never heard anti squat talked about, but I have had that horrible "BA-BA-BA-BA-BA... squeak!" coming from the back axle when it isn't quite spinning the wheels, but it is jumping around.

 

The steering is light on my car, but I've never thought it to be vague, just lighter than other cars, check your pressures, you don't have coilovers do you? Is your tracking right? I have zeta S coilovers and have them near the middle of their range and almost at full ride height. The car is a bit higher at the back and a bit stiffer too but it is just right for me, the back end follows the eager nose and lets go just before.

 

Take your spare tyre out the boot try and get the CofG forward an inch.

Interesting mate, I've never heard anti squat talked about, but I have had that horrible "BA-BA-BA-BA-BA... squeak!" coming from the back axle when it isn't quite spinning the wheels, but it is jumping around.

 

The steering is light on my car, but I've never thought it to be vague, just lighter than other cars, check your pressures, you don't have coilovers do you? Is your tracking right? I have zeta S coilovers and have them near the middle of their range and almost at full ride height. The car is a bit higher at the back and a bit stiffer too but it is just right for me, the back end follows the eager nose and lets go just before.

 

Take your spare tyre out the boot try and get the CofG forward an inch.

cofg forward an inch?

Centre of gravity, I can feel the difference between a full boot and an empty one. Don't know how much it will affect front grip, in theory it will be a bit better, but will make the tail easier to get back into line.

When did you have an alignment done last? Anti-squat at the rear is to try and prevent the front going light, side effect being less weight transfer to the rear and more wheel spin

come to think of it i have got a lot of sit h in the boot at the moment and with nice stickies on the back i dont want a drag car i want to feel safe as i hit the 70 mk 3rd start to come in, dont matter until i can get the balance right ill be stiking to the 30 mph limit around here of course.

How could you even adjust that angle on a z32 the angle is preset and fixed is it not?

How could you even adjust that angle on a z32 the angle is preset and fixed is it not?

 

i dont want to change the angle of the z32 i would and would be nice to be able to use the power of the car without feeling that the fronts not planted aswell, at the moment it fells like a light weight gto up front that not good, that said i dont want to drive a go cart either if you get me.

Mine only feels light when I'm going too fast to be on the road tbh not ie very very rarely. Even then it's the back end that feels a little floaty and loose. I blame the hicas for this mostly.

When did you have an alignment done last? Anti-squat at the rear is to try and prevent the front going light, side effect being less weight transfer to the rear and more wheel spin

 

the cars alightment was done a few years back but that said then the cars been off road for years and ive got new tyres and sizes and it might be that the shocks are cream crakered as well.

I would start with a refreshed suspension setup and alignment before you start trying to change other things.

it would be nice to have a drive in another tt300 to see if its just me, but i know its the car i used to be comfortable doing 90 with no hands on wheel , i know someones going to say why would you but im mearly demenstrating that when set up right you can feel everything thats going on and comming. dont want a car thats going to do stuff that i didnt make / feel it do. thats how accidents happen.

Mine only feels light when I'm going too fast to be on the road tbh not ie very very rarely. Even then it's the back end that feels a little floaty and loose. I blame the hicas for this mostly.

 

well this will be another reason whilst mine is soon to replaced with an NA rear end with no hicas. at least that will be out the aquation

I would start with a refreshed suspension setup and alignment before you start trying to change other things.

 

ill get that done once the na rear end is on mythinks

this is what i found and is reading is great read, just needs to find someone to be able to drive mine up the road a couple of miles and say this is what you need to do or have done.

Originally posted on Texas nissans

 

Part 1: Four steps to better handling

 

Suspension tuning is the black art of compact performance. With the majority of the world concerned about making horsepower, handling has traditionally taken a back seat. However, as all serious geeks know, every fast, well-rounded street car has as much suspension tuning as it does power tuning.

 

With the popularity of drifting, time attack contests and racetrack hot lapping on the rise, suspension tuning and handling are becoming popular with enthusiasts who previously spent all their efforts making power.

 

Finding straight-line horsepower gurus to help you is relatively easy, but it's much harder to find an expert who can make your car corner well. What’s the solution? Make yourself a guru. If your automotive interests are greater than a one-dimensional urge to blast straight down the 1320, then it's time to get to work.

 

In this series, we'll uncover the mysteries of car handling one at a time. This month, we begin with the four fundamental first steps.

 

Step One: Sticky Tires

 

Tires are by far the biggest contributor to finding more cornering force. By bolting on a set of stickies, you -in minutes- make the biggest possible gain in cornering power. Generally, putting the biggest tires that will fit inside your wheel wells without rubbing is the way to go. Choosing an ultrahigh-performance tire is also important.

 

The list of sticky street tires is miles long. Below are a few of our favourites organized by cost. The cost-no-object tires will ultimately yield more grip than the value-priced tires, but in most cases, the value-priced choices offer 90 percent of the performance of the more expensive tires at 60 or 70 percent of their cost.

 

Some of our favourite ultrahigh-performance street tires:

Cost No Object

Michelin Pilot Sport and Pilot Sport2

BFGoodrich g-Force KD

Bridgestone Potenza S-03

 

Value Priced

Falken Azenis

Kumho ECSTA MX

 

If you're attending track events, auto crossing or simply wanting the most grip possible, try a set of DOT-approved racing tires. Some can be used for everyday driving, while others grip almost like racing slicks and last only slightly longer. These tires produce more road-sucking grip than any suspension mod you can make.

 

The drawbacks are many, first, these tires can be expensive; second, they wear quickly; and third, the number of heat cycles their rubber formulations can withstand before losing significant grip is limited. Many of them don't do well in the wet and none work in the snow or ice. It's possible to end up with expensive, fast-wearing and not-so-grippy tires by using them on the street and by subjecting them to too many heat cycles. Most users of these race tires use them only on the track.

 

DOT-approved street-legal race tires:

Durable Enough for Street Use

Yokohama A032R, Yokohama A048

Toyo RA-1

Nitto NT 555 RII

Hankook Z211

Pirelli P Zero Corsa

Michelin Pilot Sport Cup

Avon Tech R

Kumho Victoracer V700

 

Track Only

Hoosier A3S04, Hoosier R3S04, Hoosier Radial Wet

Kumho ECSTA 710, Kumho ECSTA V700

 

Generally, it's possible to stuff a tire two sizes larger than stock into most cars' wheel wells. For instance, a car that came with a 185/70-14 tire on a 5-inch-wide wheel can usually accommodate a 205/50-15 on a 7-inch-wide wheel. Putting the tires on a wheel of the recommended width is important as well.

 

Going up and inch in wheel diameter and running a lower profile tire is a good thing. A lower profile tire has shorter, stiffer sidewalls, which improve response to steering inputs and hold the tread flatter to the road surface during cornering load. However, it can be overdone.

 

Ultra low-profile tire are more sensitive to suspension tuning and camber changes. And stiff sidewalls don't conform to road surfaces easily. This makes ultra low-profile tires sensitive to shock, as the short, stiff sidewalls have very little compliance. Harsh surface inputs can make these tires skip and hop across the surface instead of digging in and finding grip. Large wheel and tire combinations also increase rotating and unsprung weight.

 

For example, most enthusiasts driving small-bore four-cylinder front-drive cars run 17x7-inch wheels with a 205/40-17 tire. The big wheels and low-profile tire look cool, but this combo is too large and too heavy for optimal performance. Hard-core track geeks driving these same cars almost always fit a lightweight 15x7-inch wheel with a 205- to 225/50-15 tire.

 

Huge wheels also increase your car's final drive. Their added weight increases the flywheel effect, slowing the car's acceleration and increasing load on the brakes. This means a wheel larger than 18 inches are rarely used for performance, so even for large cars, 18 inches is the maximum practical wheel diameter. There are few choices for DOT-legal race tires larger than 18 inches anyway.

 

Huge wheels can greatly increase unsprung weight - the weight of the components that aren't suspended. This includes the suspension arms, brakes, half of the shock absorber and the wheel and tire.

 

For the suspension to work well, the ratio of sprung weight to unsprung weight must be kept low. The best example of unsprung weight hurting handling is found on monster trucks. Even though they have wheel travel measured in feet instead of inches, it doesn't provide a significant measure of driver control.

 

This is why monster trucks have nearly as much unsprung as they have sprung weight, thanks to their huge tires and axles. This makes the shocks work much harder to damp wheel movement. Reduce unsprung weight and the suspension doesn't work as hard, the ride improves and the tires stay in contact with the ground.

 

The obvious way to make up for the disadvantages of increased wheel diameter and width is to use a light wheel. Light wheels are easier to accelerate and brake. They also reduce unsprung weight. Some examples of our favourite light wheel can be found in the table below. The mostly expensive wheels listed on this page are forged or semi-solid forged. These processes improve the grain structure and provide superior strength for the weight.

 

Light wheels:

Cost No Object

Volk TE37, Volk CE28N

Rays Gram Light 57F

SSR Competition X, SSr GT2, SSR GT1, SSR GT7

5Zigen FN01R-F

Motegi Track Lite

Centerline Impulse

BBS RC

 

Value Priced

Axis Mag Lite, Axis Reverb

Kosei K1 Racing

Almost all Rotas

Enkei RPF1, Enkei NT03-M, Enkei RP03, Enkei RS+M

Rays Gram Light 57C

Team Dynamics Procomp, Team Dynamics Pro Race

 

Beware of some of the other lightweight, low-cost wheels offered on the market; we've found many of these bend like butter, sometimes just from normal track driving antics, like hitting FIA curbs or dropping a wheel off the track. The value wheels we have listed either have a history of surviving race conditions or are wheels we've had personal success with on the track.

 

 

Step Two: Reduce Body Roll, Dive and Squat

 

The most important basic suspension trick is to reduce excess body motion. Roll under hard cornering, dive under braking and squat under acceleration all create problems for the driver.

 

Contrary to popular belief, roll doesn't cause weight to transfer to the outside wheels. Rather, it hurts handling by slowing chassis response to steering, braking and accelerating - all critical inputs for controlling the car.

 

Body motion also gives the impression the car isn't handling well. Roll, dive and squat all contribute to a lack of confidence behind the wheel. Watch a F1 car in a turn; it nimbly darts around the corner with no excess body motion. Now watch an SCCA showroom stock racer; it leans, squirms and squeals its way around the track. Extreme example, sure, but exactly the heart of the problem.

 

More insidious are the other side effects excessive motion produces. Many softly sprung vehicles will roll and bottom the suspension on one or both ends when cornering hard. This shocks the tires and will cause an instant loss of traction on the end that bottoms out first; the result usually involves a track tow truck.

 

Moving the suspension through a wide range of travel can also result in another problem. Most factory vehicles have compromised suspension geometry and several problems can occur when a car heels way over in a turn. First, the suspension can gain positive camber. This is worse in cars with McPherson strut suspensions. With strut-type suspensions, the car rolls, but the tires don't. This forces the tire to roll onto its outside edge and reduces its contact patch - clearly not the best way to use a tire.

 

The other evil effect of roll is bump steer. Bump steer is caused when the steering linkage and the rest of the suspension travel in different arcs throughout the range of motion. As a result, the tires can give steering input even if the steering isn't moved when the car heels over. This translates to the driver as a twitchy and unstable chassis. Combine dive and squat and all of these problems add up to a serious lack of control.

 

Now that you know body motion is bad, what can you do to control it? The first thing to do is run stiffer springs. Stiffer springs will resist roll and bottoming out under roll and combinations or roll, dive and squat.

 

Of course, stiffer springs have more rebound energy. To prevent your car from bouncing like a pogo stick, you need shocks with more damping. Shocks don't affect how much a car rolls, but they do affect how the suspension responds to bumps and steering input. More rebound damping keeps the car from bouncing and floating over bumps and undulations. More damping also makes the car more responsive to steering input. Too much rebound damping can prevent the suspension from returning once compressed, causing it to pack down and gradually bottom out.

 

Another way to reduce body roll is to install larger anti-roll bars. Anti-roll bars are torsion bars that connect the wheels. They don't come into play until the car stats to roll in a turn. During roll they must be twisted for the car to lean over. Anti-roll bars don't affect the ride as much as stiffer springs and have no effect on dive or squat. Generally the shock damping doesn't need to be altered when the anti-roll bar diameters are changed.

 

Stiffening the suspension will degrade the ride, and it's easy to make your car too stiff. If this happens, the suspension will not be able to deal with bumps and will hop its way around turns instead of compliantly absorbing the bumps and finding traction.

 

Step Three: Balance the Chassis

 

Now that you've reduced body motion and improved steering response, we can work on the next major area of improvement. The goal for most of us is to have neutral balance, where all four tires slide the same amount, is the fastest way around a corner most of the time. This way you use each tire's maximum grip. It might seem odd, but many experienced drifters prefer a neutral car because it allows them to have many control options for getting sideways.

 

Unfortunately for the enthusiast, most cars are factory tuned to under steer. Under steer occurs when the front tires slide first when at the limit. Manufacturers do this because it's the easiest handling mode for the average driver to control. Under steer isn't efficient for extracting maximum literal acceleration because the car will use the front tires excessively, while the traction contribution of the rear tires is wasted. It's also the slowest and most boring way around a corner. Bottom line? Under steer sucks.

 

 

 

If we go too far in the quest to eliminate under steer, we inevitably create overseers. Overseers occurs when, and the limit, the rear tires slide before the fronts. Drifters work at controlling and driving in a state of continuous overseers, raising it to an art form. Overseers can make you a hero or a douche bag. Do it well and everyone will love you. Do it poorly and they'll laugh when you're riding home in the flatbed.

 

 

 

How do we tune a car's handling balance? By manipulating the tires slip angle. Slip angle is defined as the difference between the direction the tire is moving and the direction the contact patch of the tire is pointing. At extreme slip angles, the contact patch actually slides across the pavement.

 

 

 

The primary dynamic contribution to slip angle is the load placed on each individual wheel while cornering. A greater load on a given wheel/tire results in a greater slip angle of that wheel/tire when subjected to a sideways cornering force. A nose-heavy front-wheel-drive car has more weight and thus cornering load on the front tires. The front tires start to slide first, causing under steer. A rear-engine car has a larger proportion of its weight on the rear tires. The rear tires run a larger slip angle so the natural tendency is to overseers. A mid-engine car usually has the most even weight distribution with near equal slip angles from the front and rear tires. This creates more neutral handling.

 

Properly manipulating tire load and slip angle by controlling weight transfer is key to balancing the chassis. By altering weight transfer and tire loading during cornering, much can be done to change the car's natural handling tendencies. Can you make a nose-heavy front-wheel-drive car overseers? Sure. Look at the most successful front-drive race cars; they overseers like crazy.

 

How does a tuner manipulate tire loading and slip angle? By tweaking the spring rates, anti-roll bar rates, tire sizing and pressure, and to a lesser degree, the shock damping. The first option a tuner has is to increase the tire pressure. The harder a tire is inflated, within reason, the smaller slip angle it develops. In the case of a nose-heavy front-wheel-drive car, if you add several psi to the front tires and take some pressure out of the rear, the front tires' slip angles will increase. This alone can do quite a bit to reduce under steer.

 

Changing the spring rate and anti-roll bar rates has a large impact on slip angle. Running a stiffer spring or anti-roll bar on one end will cause more weight to be transferred onto the outside tire as the car tries to roll in a corner. The softer end will compress and the more stiffly sprung end will resist compression, putting more weight into the tire and causing it to run at a bigger slip angle.

 

The best thing to do for you’re under steering, front-wheel-drive car is run a bigger anti-roll bar to tune out under steer. Conversely, stiffening the front suspension and increasing the rear tire pressures can tame overseers.

 

Shocks can improve response and help balance the car right after the indication of a turn; soft shocks get the car to a steady point of weight transfer faster. When stiff, they can delay weight transfer. Thus, shocks affect how the car feels at turn-in and also how it feels past mid-turn. A car with the shocks set fairly hard will turn in sharply. If the shocks are set too hard, the balance might change later in the turn in an unpredictable way as the heavy damping slows the body roll and weight transfer.

 

Tire sizing can also affect chassis balance. Installing a wider tire on the end that needs traction most is obvious. Rear-engine Porsches have wider rear tires to help prevent overseers. Powerful rear-wheel-drive cars tend to have wider tires in the rear than in the front. Many front-wheel-drive auto crossers and road racers install a wider front tire to get more front grip.

 

At the limit of adhesion, a car that slides all four wheels without brake or throttle input is considered ideal; it also doesn't exist. Being able to provoke slight overseers by lifting the throttle and more aggressive overseers with slight braking while cornering at the limit is useful as well. Being able to slow rotation with slight throttle application makes front-wheel-drive cars easier to control.

 

Rear-wheel-drive cars should also be able to invoke overseers with large applications of throttle. This kind of balance gives the skilled driver the most options.

 

Step Four: Weight Transfer

 

Weight transfer is the movement of weight from the inside to the outside wheels during cornering. Excessive lateral weight transfer hurts handling. It's caused by centrifugal force working on the chassis' centre of gravity, which loads the outside wheels and unloads the inside wheels.

 

Contrary to popular belief, very little weight transfer can be attributed to lean in a corner. Even at large roll angles, weight transfer due to roll is quite small. So lowering a car's centre of gravity and widening its track width will reduce weight transfer more effectively than reducing roll angle.

 

Lowering is best accomplished with shorter springs. The smartest approach is to use shorter springs and shorter-bodied shock absorbers or struts that maintain stock compression travel at a lower ride height. Excessive lowering can change suspension geometry, causing positive camb4er during roll and contributing to increased bump steer.

 

The easiest way to increase track width is to use wider wheels and tires that fill out the wheel wells. This also increases the amount of rubber on the road. Using wheel spacers and wheels with a more positive offset can also increase track width. Any positive change in track width, and therefore offset, increases the scrub radius. Scrub radius is the distance from the centreline of the tire's contact patch to the point where the steering axis intersects the ground, also know to regular readers as "The Dave Point." Increasing the scrub radius allows forces generated by the tire more leverage to act on the steering. To the driver, this translates as torque steer under acceleration and braking.

 

 

 

To minimize the change in scrub radius, it's important to try to increase wheel width to the inside as well as the outside by paying close attention to the wheel offset. This puts more rubber on the road and increases the track width while maintaining the same scrub radius.

 

Increasing track width also changes the motion ratio of the suspension, which effectively reduces spring and anti-roll bar rates. Lastly, a very positive offset wheel puts a large strain on wheel bearings, ball joints and steering linkage, making them wear much faster. All of these are good reasons not to go overboard with this method of increasing track width. A good rule of thumb is its safe to use the largest wheels and tires you can stuff in your stock wheel wells by rolling the inner fender flange.

 

A good guideline is to increase the track width and lower the car more on the end that slides first in a corner. An understanding, nose-heavy, front-wheel-drive car can use more track width in the rear. This play on physics will help you reduce weight transfer in both cases.

There must be something wrong cause when mine was last on the road, around town if it was wet or icy and I give it some the rear will go and it can be tricky but on the motorway mine so stable. It seems to feel like it gets really heavy and can't move it.

 

Did you say in one of your threads u were having speedo problems, cause that can make the cars steering light.

 

Mine at a certain speed steering gets heavy to make it better at higher speed.

 

I had a time before when mine was very unstable and hicas bushes were gone I changed them and it was better but not quite right, checked everything and had a shock gone replaced that and the difference was unbelievable,

Had cars with shocks gone and would be floaty but the zed was literally dangerous.

There must be something wrong cause when mine was last on the road, around town if it was wet or icy and I give it some the rear will go and it can be tricky but on the motorway mine so stable. It seems to feel like it gets really heavy and can't move it.Did you say in one of your threads u were having speedo problems, cause that can make the cars steering light.

 

Mine at a certain speed steering gets heavy to make it better at higher speed.

 

I had a time before when mine was very unstable and hicas bushes were gone I changed them and it was better but not quite right, checked everything and had a shock gone replaced that and the difference was unbelievable,

Had cars with shocks gone and would be floaty but the zed was literally dangerous.

 

yes Terry thats what i mean ,years ago it seems to drive like a big fat heavy cruser only but a fast firm planted one. now years on now im back in it it feels like super fast dingy that floots on the surface to much, im trying to get back that safe planted feel of a battle ship that sits firm and cuts through the road were you point it not feeling like it wouldnt. i used to drive mine down to dartford and quite happy sit in the outside lane doing 90 and the car would feel planted. i drive up the road at moment and doing 60 in the wet just dont feel the confadence in her ability to hold like she used to. also i know its a long time i had her of the foad but to me she feels to bouncy as well ,whitch is why im thing about the shocks

I have a pair of rear shocks here I bought them fitted them and done about a thousand miles then got meister r coilovers.

There original nissan I bought from z centre, there all built up with standard springs.

 

Only problem they may have is I stone chipped the underneath of my car so they may have some overspray but it wont hurt them.

 

If u want them pay postage there yours for free.

 

Tried selling them before and nobody was interested but there brand new so don't want to bin them.

 

Check your hicas bushes too cause that may make the back float around making it feel weird on the road.

very kind terry might take you up on that very kind offer. cheers mate ill have those

No problems u want them there here atleast there go to use not the bin.

cheers Terry sorry for that last post i got interupted with somthing. Yes mate ill have thos off you for sure mate, nice one. i know that the hicas unit has a tiny bit of play in it so that wont help at all for sure ,thats why i bought the na rear end to gat rid of that killing to birds with one stone no hicas anymore and a faster set up to play with ,whilst having no hicas to go wrong. im going over two my brothers garage tonight to get these brakes bleed again doing my head in, once there done ill play with the clutch ajustment to get rid of that free travle. can you pm me your tel number please i would like to speak to u about somthing else m8. thanks

If u pmw yours I'll call u mate I don't know how to get it out my phone lol