If you ahve short stroke shocks and you have only a tiny amount of droop, it means your car isnt low enough for your shocks.
This is about the roll steer/ rear steer / what other name people call it
If you watch enough top level motorsport (F1 , V8 Super cars) ,
you will see they all run that type of rear suspension geometry.
It improves all facets of cornering
Where people get unstuck ,
is when they use the:
"People with Nissans remove HICAS , so that means I need to lock up my rear end"
The real reason , is that it is a Hydro/Electronic System, and It isn't predictable.
One more thing , inexperienced drivers , don't have the skills and experience ,
to be able to diagnose there handling issues.
99% of a cars speed is the Driver
If you ahve short stroke shocks and you have only a tiny amount of droop, it means your car isnt low enough for your shocks.
RT142 Estate.
AJPS.
changing to the softer 7/5 spring set up should give you more droop as the car will sit lower and the shocks will be in a better range of stroke, if you have minimal droop the shock's stroke is significantly reduced as the shock is being held nearly on full extension.
optimal stroke is a dark art it seems, i always thought mid stroke was best and its still what i aim for. different motor sports though vary in whats the best range. thats a whole new can of worms.
rebuild your coil overs with a spacer under the insert.
78's
Pretty much what slydar said, you need to rebuild the front coilovers with a spacer under the strut insert to in effect raise the insert in the strut and allow more droop. As previously mentioned, i'd aim for about 2-3 inches of droop from static hieght to allow for this countries fine roads (not). For the rear, u need longer shocks, plain and simple. measure what you need and head to a parts place (not supercheap) and find a monroe or gabriel parts book, look thru it till you find something with the apropriate length (comodore, celica, seirra shocks are a good start)
I can put up a few basic pics to explain all this for people if the demand is there, i'll have to draw it up though.
GILLY: what you said about aiming for the middle of the stroke is not a bad idea, if you have shocks with a very short stroke.
The koni dampers I'm going to be ordering soon have a stroke of 153mm front and 143mm rear, so in this case your theory would be pretty good.
However they make dampers that due to there design have anywhere up to 300mm of stroke, now in that case (depending on application) i would be running whatever droop is apropriate and leaving the rest as compression.
HATZO: agreed on the drive car comment but i have no idea what you are talking about with the whole rest of your post, roll steer is bad, plain and simple, as the car rolls into a turn roll steer causes the car to get toe changes (in effect) that cause the car to under/oversteer. The only way that this may be used is if a chassis is over powered for a particular circuit or to solve another problem. For example, say an light sedan (corolla, escort etc) has like, 400kw's, because of the shitty aero traits that this vehicle has it will be a handfull at high speeds, you may want to dial in a little roll understeer to make the car more stable at speed. I can't think of any other reason to have rear roll steer on purpose in a racing sense. Genrally, the problems that roll steer fixes are caused by something completly different that can't be changed (due to class rules for example, ie aero inefficiences).
Unless you are talking about something to do with adjustable rear rollcenters?
SR_Rolla: whats your views/opinion on shortening the LCA, and redrilling the mounting point for the LCA on the crossmember further out? Hypothetically if u redrilled the hole further out by 40mm, then shortened the LCA by the corrosponding amount what kind of effects, both negitive and positive would it have.
not looking for a flame war or "why the fuk would u do that" but just curious.
In theory, it could work, if i was to be trying this mod though i would be concerned about bump steer problems to do with shortening the LCA. I'd move the inner mount outboard, get a spare set of LCA's with new bushes and ball joints that are stock length and then get some shortened ones, also with new bushes and balljoints. Then i would get hold of some adjustable strut tops and a spirit level. 1st i'd get a wheel alignment, then do a few runs of either a road that you know really well or a race track, with stock LCA's at the standard inner mounting point. Bring a mate and take some notes about corner speed, rpm, how the car feels etc. After that do your mods to the inner mounting point but put the stock LCA's in, then get it wheel aligned to all the previous neg/caster/toe settings and go for another run, take notes etc, then put the shortened LCA's in, wheel alignment to previous settings/test again.
This is really the only way to properly see if it has a reasonable effect or not. My guess is it wont have a real positive effect but thats just my personal opinion. Go nuts and try it if u feel it may work.
Thanks for that, ok no more hypoteticals here, I'm running the S13/14 crossmember in my KE, and have stock KE LCA's on there, obviously the LCA mounts on the LCA is much much further out compared to stock (and i have the camber to show for it) Now i am trying to make it all work and work well.. just to get the car going i rigged up the stock KE susp, stock struts and springs and all... whilist it works, its a little on the bump steery and vauge side.
So I'm in the process of running the nissan stuff in terms of brakes, hub, strut etc, makes sence since the rack and crossmember is all nissan, so should work reasonably well...
my biggest prob is, i can't run the standard length S13 LCA, since it is miles too long and combined with the LCA mounts on the Xmember which are further out already in relation to the K Xmember, the track os going to be huge.
So.. was thinking of still running all the Nissan stuff, with S13 control arms, but shortened, I feel that bump steer should be eliminated compared to the K series susp due to the steering arm linkage point being matched to the rack location.
Cheers!
bump steer may be eliminated but unfortunately everthing else ends up stuffed. basically, the only way to run nissan stuff properly is to A) run stupid wide track and + offset wheels, or B) shorten the LCA's like u said and move the strut tops in a similar amount.
Sorry to break it to u but it just doesnt work well, the ackerman angles are stuffed, the front 2 rear track is stuffed, and even if u do alter the rear track to suit the front the car ends up over-square and it wont handle anyway.
Theres a reason beau yates and co. don't tend 2 do this mod, and if it was an awesome mod they would use it in N2.
Sorry dude if that destroys your ideas but thats what i have found from what ive researched
What may fix your problems is to used ae86/ke70 style struts and LCA's and redrill the crossmember 2 bring it back 2 stock position, then adjust the bump steer out of it. It is posible and way easier than making the nissan stuff work
yeah but redrilling the LCA's further IN (back to where stock KE/AE mounts would be) is an ideal solution, however then you regain the bumpsteer due to the rack end (tie rod) and LCA pivot points being totally different.
I used to run s13 susp in my drift ae86 back when i was drifting with beau before anyone knew who he was.. and while it was slapped together, it worked reasonably well., however i was using a AE86 crossmember with cut and shut s13 LCA's and overly stiff coilovers.
this time round, i'm looking at doing things a little differently.... I'm with you tho, on paper it seems it may not work, but i'll give it a go and see what happens, if worse comes to worse i'll redo it all