Suspension Question
 

Right this has been bugging me for ages!

Basically everyone says don't go any lower than 40mm or your handling will suck dick.....if so why are all touring cars slammed on their arse and mm's away from the floor yet fly round corners with ease.

omg such a noob baz

they are lower due to lower center of gravity, the cars are made so the track rod ends etc... run at this angle.

when you lower a car such as a saxo its not DESIGNED from scratch to do so, so you get dodgy camber and in worst cases bump steer.

also most companies also only make soft springs for lowness, i car like that will run fucking hard suspension

race cars suspension set ups and steering systems are developed costing lots to work together, somthing that 60mm PI springs are not lol

Because they thinks they is bad lowerrrrred 120mm

yeah just to add to what ryan said...


when designing a suspension geometry quite a bit of time is spent carefully determining the tie-rod length (thing that move the wheel about the steering axis) to suit...

When you add some well phat 60mm lowering springz that suspension geometry is modified resulting in an incorrect tie-rod length. the result is that when the suspension is subjected to a disturbance (a bump for instance), the wheel will either toe-in or toe-out (dependant on whether the tie-rod is now too long or too short)... and bosh you get the term 'bump steer'... a few saxo's that have binned it 'randomly' could well have had an case of bump steer.

anyone who says their handling is 'mint' now that its lowered 60mm is talking poo poo or doesnt know what they are talking about.

in addition... the change in suspension geometry will alter the position of the 'instantaneous centre of rotation for the vertical motion of a wheel' this is turn modifies the location of the body roll centre... which again stuffs up the handling.

Also camber angle gets naffed up, which lowers the lateral forces generated by the tyres as there is less tyre in contact with the road surface.

People may take the piss out of Matt Yates' setup (lower about 3mm or something) but fookin hell that thing holds the road like no other saxo I've ever been in.

but 60mm is proper bo bruv and it handles like on rails init!

Rails maintained by Network Rail

hahaha, didn't see your post until after my edit.

im still awaiting the 60mm cru to come on banging about how well their car handles and has done for however many years etc.., and that physics is wrong, and geometry comments are wrong!

hahah I'll look forward to it

If they want to argue against you and me (im doing my masters project on suspension geometry optimisation) then let battle commence....

this is Sax-P not SSC. We is all well clued up on what good suspension is ;)

they will still argue, as the constant arguments ive had they have never been able to back up comments with anything other than that they dont give a fuck about geometry and im wrong their car is awsome LOLO

abit like ebay chips eh ;)

yeah they've got you there like...:err:

really they still argue?

repeatedly!

lol!

I'll get my gun...

ill get my 60mm springs ;)

good one...


this may go over most people heads but for those that are interested... the tie rod length is determined through this geometric plot...



if you know Point E, D, G and U or T you can determine the position of T or U respectively.
E is the top of the strut
U-T is the Tie Rod
G-D is the lower wishbone length.
P1 is the Instantaneous Centre of Rotation for the Vertical Motion of a Wheel i.e. the theoretical location of the pivot point

if you lower the suspension, and thus lower the position of E you can see the tie-rod length U-T is invalid.

Sayer is gonna be master of fuel consumption and Saxo handling?

When I started building the 309.. we determined the final ride height of 3 inches ground clearance. (with the chassis on wood..) before working out where the suspension mounts were going to be located. May seem back to front way to do things but really its the only way to maximise the handling.