obviously most would agree that mechanically the z32s greatest fault is space, that engine is in their snug! which causes and creates a whole hoast of other issues. however thats not what im thinking about, been thinking about bobs car today and how well it goes round corners. thinking back i seem to remember pete saying that nothing drastic had been done to the chassis. so what is it about the stock setup of the z32s suspension that makes it less good through the turns than many other sports cars of a simular weight class, im led to believe the z33 and z34 go round corners far better? obviously other cars of a simular age im thinking yank tanks have issue slike crappy leaf springs etc but the zeds quite modern under there with the double wishbones etc and our cars use quite a few of teh same parts that are used in teh skylines which are renowned for great handling. so i guess what im asking is whats the best way to make a z32 go round a bend faster and under more control, and what is the major limiting factor in that game.

The Z's Achilles heel is its autobox...not its suspension setup. ;)

 

The Stock setup is pretty good, and the biggest reason a new 350z/370z may "handle" better through the twisties is far more about the condition of the Z32's 20yr old setup than anything else. Dampers, Springs, Bushes and Alignment are WAY past their expected lifespan these days, yet so many are running on entirely original components.

 

There are however many factors to suspension and chassis design that affect vehicle handling.

 

Many of which are going to be fairly common knowledge -

 

Suspension type - Double Wishbone, Multilink, McPherson, Solid axle, leaf ..etc

Vehicle Weight

Centre of Gravity (horizontal and vertical weight distribution)

Wheelbase

Track

Spring rates

Chassis Stiffness

Unsprung Weight

Tyre choice

 

But then you have the finer technicalities of suspension geometry. Not just the usual Static Camber, Castor and Toe many will be familiar with, but more advanced parameters defined by the geometry of each suspension and steering point such as Static roll centre position, Scrub radius, KPI angle, Steering arm length, Kinematic trail, anti-dive and anti squat properties, Damping ratio and Sprung mass natural frequency which all have an affect on the dynamic properties such as Roll centre migration, Rate of Camber, castor and toe change per-G of Lateral and longitudinal acceleration and dynamics such as weight transfer to each wheel and even driver feedback.

 

The point is that suspension design is a very complex affair, and there is no optimum setup for every scenario. Road cars in particular, even higher performance road cars are always designed with Compromises - Typically comfort, cost and the need to withstand the abuse of poor road conditions, but even finer details like the amount and sort of feedback sent back to the driver and the natural understeer/oversteer tendancies of the vehicle - the need to cater to the masses.

 

The Z32 was praised for its handling when launched, but its fair to say that Nissan's Intent was for it to be a high performance Sports GT, while the Z33 and even more so, the Z34, were said to be Nissan's attempt and getting back to its 240z routes as a back to basics nimble sports car. The Z32 was aimed at a much higher market and its cost and more prestige feel reflected this. Despite the comparable weight and suspension setup these design influences would of led the overall suspension design goals.

Edited December 21, 201213 yr by Yowser

btw, the Z32 uses a near identical multilink setup to the the Skyline GTR.

 

(A Multilink setup could be referred to as a type of Double wishbone setup, with its dynamic benefits along with the extra benefit of improved comfort - but with added complexity, cost and usually weight.)

 

However Nissan made alterations to some of the rear lower arm geometry to the R33 and R34, which would of had an affect on the vehicles anti-squat properties as well as potential differences to the Dynamic nature of much of its geometry. If I ever get the chance I had planned to investigate this further by plotting the new and old points in Kinematics software and comparing the results.

http://www.aus300zx.com/forum/showthread.php?t=298056

 

It's a long thread now but this fella from UAS on the Oz site changed the front pivot point of the upper camber arm and a load of other bits and reckons it's a whole lot better than stock for performance

 

That's actually about returing the suspension arm angles back to stock to make up for the fact that the car is lowered. Lowering the car is good for centre of gravity but screws up the roll centres

this is really starting to get into the nitty gritty of what i wanted and giving me some things to take away and learn on my own. im becoming progressively more interested as each day passes in they way a car works not just mechanically but design wise why things are built how they are and how changes we make change things for the better or worse sometimes.

 

i also totally agree that the car is generally better than the driver, certainly to push my zed even though its near stock on a public road would be pushing on beyond the boundaries of whats legal and driving it on its limit would be about my current level of skill, im just a normal person not a race car driver. i think ultimately what i want to achieve is a car that is comparably as controlled and grippy through the bends as a modern sports car like the z34 or similar, my car has no quams in catching most things in a straight line but the corners that make me loose confidence in it. i also want to take the car out on track a few times this coming year to actually be able to drive it properly without fear of loosing my license which i depend on for work, without being slower than something like an stock mx5 or boyed up focus, i dont really have any experiences in terms of this so i really dont know what my car is capable of in comparison to others. in reality though its not about racing i just want the car to feel liek a solid and controllable machine not an axe murder that will wrap me round the closet tree at a hint of damp.

That's actually about returing the suspension arm angles back to stock to make up for the fact that the car is lowered. Lowering the car is good for centre of gravity but screws up the roll centres

 

Do you think it's worthwhile for what you and Bob do?

Do you think it's worthwhile for what you and Bob do?

 

yes it is, though it's a lot of work to do. I'm trying something on the rear to get the same effect, will report back next year if it works!