First off i am running apex gen 2
Ok so my car is not that low but i have noticed that when i hit a bump when cornering they wheels do come in contact with the body.
I am wanting to go lower but don’t want to have to buy different coilovers
If i was to up the preload on them to say 15mm which i know is 10mm above the 5mm guideline would this help the problem and what sort of adverse effects would his have on the cars handling.
Not to bothered about the long term affects on the coilovers
It would possibly lower it another 10mm,but I think it have a terrible ride quality,like really bangy crashy over small imperfections in the road
let alone pot holes etc as the spring will be more compressed and under more tension is what I'm thinking,
I haven't tried it myself btw I've only gone with normal 5mm spring pre-load
And car must be very low already if you have run out of adjustment tbh
Its not that i cant go lower by adjusting the coilover and not the preload its the fact that when cornering even at the high im at, at the moment the wheels come in contact with the car.
I am wanting to go lower but think this will make the fact that the wheels are contacting the inner arch even worse so im wanting to up the preload to stop the car hitting so much
The car is fully adjustable arms and i have had the geometry set up so don’t think my caster is out
OK Swap the springs for a harder spring rate and/or if not fitted a harder/stiffer anti-roll bar
,and modify the arch liner were its scrubbing,or cut them down so just use the rearmost part
to stop crud going into the wing and sill area
the arch liner is not as close as it could be in places,check were its rubbing and may be cut that section out?
Raise the ride height.
OR
Use skinnier tyres.
OR
Run more camber.
OR
Use different wheels with more offset.
I'm NOT the Chairman anymore, Ken was. He still likes poo though. Its not Jim either now. Ooh ooh, its now Doc!
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Opie Oils : MOT-a-Car : DriftWorks
OR
Crank the damping up and live with the shitter ride quality.
Why is the spring preload adjustable if nobody runs more than 5mm? I say, wind it up another 5mm or so and give it a go.
Uprate the ARBs and fit strut braces.
That will remove the body roll when cornering and MAY stop the wheels hitting the arches when cornering.
I'm pretty sure increasing the preload won't make any difference to the ride height on Apex Gen 2s. You simply wind up the collar on the body to a higher point compressing the spring. As its a linear rate spring, it won't affect static sag unless you compress the spring so much it stops working altogether.
Raise the ride height by turning the lower assembly on the body to increase the strut length.
Just changing the springs won't really work either as the damping is matched to the spring rate and the static sag will be reduced with the stronger spring so the car will be raised not lowered and you may run out of ride height adjustment.
Adjusting preload will help. If you adjust the rear, I'd adjust the front a similar amount to keep the handling balance.
Have you rolled or flared your arches?
My car handled like a pig when I had too much preload. Make sure you don't add so much that the suspension has no "droop".
What spec gen 2's are they? Where exactly is it rubbing also?
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Please explain the science with specific reference to Apex Gen 2sOriginally Posted by Brookie
How will adjusting preload help ?
id just click the dampening round a few times to make the ride a little harder, i found that just a few clicks was the difference between me scraping the exhaust on bumps and not
the car has updated arb's and caged and strut braced.
I will be upping the dampening as well as increasing the preload to about 10mm and lowering the car by about another 40mm then smacking the shit out the inner arch with a 4lds mash hammer.
It is tuching the chassis leg on bad bumps and the inner arch at the top of the inner arch think i might wind my caster in a bit to bring the wheel back a bit
Adjusting preload will not change the spring rate on a fixed rate spring, merely the force which is takes to start the spring moving - it affects the 'sag', but not the rate. All it will do is kill off some small bump sensitivity, and give you a really hash top out. You also increase the risk of coil bind (where the springs wind up and have no compression left, so bottom out before the damper does) which is a very bad thing.
Cranking up damping is not the solution either. You will put more pressure on the damping circuit, and most likely still get the problem with big hits, and when pushing hard into corners. You'll also make the ride quality more balls, run the risk of packing down over successive small bumps (because the shock won't return quickly enough to be able to handle the next bump) and lose traction as a result.
You either need to make the clearance inside the arches, raise the car, or increase the spring rate (and possibly have to revalve the damper unit to suit).
Preload only really has two main functions: to tune the sag of the car(useful in corner weighting and adjusting the extension into dips etc), and to hold the spring in place. For anything else you need to be looking elsewhere.
Sorry, now that I've thought about it, I may have been chatting poo a littlePlease explain the science with specific reference to Apex Gen 2s
How will adjusting preload help ?
...just flare your arches and be done with it
Ultimately, if the wheel can hit bodywork anywhere in the travel, then no spring rate is really right. You should look at either raising ride height or adjusting the bodywork/chassis.
Easy to check on the rear - just put the car on axle stands, take the shock off, disconnect the ARB, and jack the wheel up through its full range of movement (in fact this is probably over cautious as there's probably less travel than that in the shock)
The front is harder due to the mac strut design - you need to remove shock, remove the spring, then refit, disconnect ARB, then run the wheel through it's full range.
Roll your arches, it helps a lot...
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