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View Full Version : Poor weight distribution, can this be made to handle?



spetz
11-07-2006, 05:35 PM
So, my car has 740kg over the front wheels and 380kg over the rear wheels (no spare tyre, low petrol etc)

I can move some stuff from engine to boot (battery), have some extractors as opposed to cast iron manifold, and will get a carbon bonnet
Also with some stereo gear, the car should have about 700kg front and maybe 430kg rear

Can this be made to handle really well with the correct spring rates, damper rates and swaybars?

aaronng
11-07-2006, 05:59 PM
Yes you can. Do corner balancing. The sum of the weight over the front left and rear right wheels must equal the weight over the front right and rear left wheels.

And get a thicker rear sway bar.

spetz
11-07-2006, 06:14 PM
I am worried with too stiff of rear suspension, that at speed the rear will be very unsettled and might just flip out unpredictably

ie. Isn't that the problem utes have? Not enough weight over the rear?
Though they are RWD I guess too

EG5[KRT]
11-07-2006, 06:42 PM
thats where setting up suspension is very important.

aaronng
11-07-2006, 06:53 PM
I am worried with too stiff of rear suspension, that at speed the rear will be very unsettled and might just flip out unpredictably

ie. Isn't that the problem utes have? Not enough weight over the rear?
Though they are RWD I guess too
I don't think you should use stiff rear suspension (springs) because there is less weight over the rear. The rear sway stops the twisting motion when you are cornering, so you will improve cornering performance.

Front springs should be stiffer than the rear. From most coilovers for DC2 and EG, it's about 10/6 which should be ok for your car.

And utes have live axles (leaf springs) for the rear suspension in order to accomodate the heavier rear payload when used to carry stuff around. Leaf springs like to bounce, that's why the rear of utes are unsettled when going over bumps.

DC5TYPER
11-07-2006, 09:09 PM
You can also run lower tire pressure at the rear due to light rear weight.

spetz
11-07-2006, 10:18 PM
The car is a lancer not a EG, so the front suspension setup is machpherson rather than double wishbone.
So, it is 5K front but the shock hooks up onto the hub making it a bit stiffer than in LSA suspension.

Rear is 4K
I am thinking of getting 6K springs at the front

It is running an FTO engine, and Cusco FTO Coilovers have 7K front and 4K rear springs
However my car is lighter than an FTO, and I am not sure of the FTO's weights front/rear
But all suspension arms, towers etc are identical between the two.

aaronng
12-07-2006, 12:06 AM
For now, what complaints do you have with your current handling? List the areas you want improved so we can give you suggestions. BTW, if the ride now is not too bumpy and rough, you can stick with 7-4 coilovers.

spetz
12-07-2006, 12:17 AM
No the coilovers are 5-4
But it has the FTO engine in it and FTO comes with 7-4 coilovers

Ok, the car understeers, and the front seems to roll quite a lot, it doesn't have any camber at the front though and the outside of the tyre is getting warn

Also, the steering is very sensitive, so at high speeds I have to keep "correcting" the car to go in a straight line.
Low speed cornering feels fine besides some understeer
But at high speeds it feels weird, I turn the steering wheel, the car turns a bit, then after say half a second or so it just sharply turns more without touching the steering wheel


These are the issues it has which I think may cuz this:

The knuckles in it (macpherson suspension) are from a Galant VR4, and the strut towers on a VR4 are closer together than FTO/Lancer. So I have camber pins AND pillowball topmounts and the most camber I can get is -0.8 on the front. Back is at -1.5 now
I am thinking this might cuz bad alignment of toe when going over bumps (that's why I need to correct it at high speeds?)
And, the reason at high speeds why it turns initially, then after .5 second it turns sharper is maybe cuz as the car rolls the toe changes heaps at the front?
I will be changing to FTO knuckles at the front soon

2nd think is the gearbox leaked oil for a good 6-8 months, and it went all over the under of the car, I am thinking this may have destroyed the bushes?

spetz
05-08-2006, 11:15 PM
No one answered :)

aaronng
06-08-2006, 12:34 AM
Whoops, missed your update. Good thing you bumped. What are the thicknesses of the front and rear sway bars that your lancer has now?

What is your front and rear toe now?

spetz
07-08-2006, 02:09 PM
Front is either 17 or 18mm
ANd rear is 18mm
They are both hollow as they are just stock Mitsubishi swaybars

I got toe at 0 all around I am pretty sure, and camber is -0.8 front and -1.0 rear.

I'll have the camber fixed up soon though as from a brake upgrade I have wrong type knuckles in there which are from a mitsubishi that the strut towers were spaced closer to eachother than my car (MacPherson suspension at the front)

aaronng
07-08-2006, 02:21 PM
Front is either 17 or 18mm
ANd rear is 18mm
They are both hollow as they are just stock Mitsubishi swaybars

I got toe at 0 all around I am pretty sure, and camber is -0.8 front and -1.0 rear.

I'll have the camber fixed up soon though as from a brake upgrade I have wrong type knuckles in there which are from a mitsubishi that the strut towers were spaced closer to eachother than my car (MacPherson suspension at the front)
Your camber sounds pretty ok. Not too bad that it would degrade your handling.

Ok, try replacing the swaybars first. The front is hollow and also too thin. I'd go for at least a 25mm hollow or a 20mm solid one. This will stiffen up the front and give you better steering response. It should fix that 0.5 second steering lag problem. But, upgrading the front swaybar like this will give you understeer, so you'll have to upgrade the rear as well. At least an 18mm solid bar. Go up to 22mm solid, but if you are going for thicker bars, you will have to reinforce your rear subframe to prevent it from tearing.

Swaybars are the cheapest handling mod at about $200 each and also the one that provides a very big handling improvement. So go for this first.

spetz
07-08-2006, 03:52 PM
I thought on a FWD it would be a good idea to have more camber at the front then back?
Cuz the car is lowered, -1 is as little as I can go on the rear
And was planning -1.5 on the front


I think the front either has too much roll, or too little camber as the outside of my tyres are getting well worn

Is there a way to check bushes? As I think they might be gone (gearbox oil leaked on them for about a year+)

aaronng
07-08-2006, 05:13 PM
Go the front and rear swaybar. The effect from those wil shit over camber. And front camber only improves handling when you are in the corner. It won't fix your 0.5 second lag.

If you are complaining of roll, go the front and rear swaybars. Do that before camber, because increasing the front and rear swaybar stiffnesses give one of the biggest improvements in handling when compared to other suspension mods.

Do you drive mostly in a straight line or always corner hard? I guess corner hard as -0.8 camber at the front won't cause your tyre to wear on the outside on the straight. I had the same problem when my car was on the track with a 14mm solid rear sway. The car just rolled too much that it couldn't keep the tyres flat on the road and it wore the outside of the tyres down in just 90 minutes.

As for bushes, if it did degrade, you should get clunking sounds from it as it would have either shrunk or degraded, leaving less material and a looser fit.

spetz
07-08-2006, 06:05 PM
There is no clunking or anything but I am thinking maybe the bushes are just really soft allowing all my arms etc to move incorrectly?
Cuz at say 120km/h+ if I start jerking the steering wheel from left to right continously, quickly, the car gets wobbly and it has no response at all. I was thinking it's just bushes flexing?

aaronng
07-08-2006, 08:05 PM
There is no clunking or anything but I am thinking maybe the bushes are just really soft allowing all my arms etc to move incorrectly?
Cuz at say 120km/h+ if I start jerking the steering wheel from left to right continously, quickly, the car gets wobbly and it has no response at all. I was thinking it's just bushes flexing?
Did this just start happening only recently with the oil leak or from way before?

Jerking the wheel left and right and getting no response sounds like swaybars that are not stiff enough to complement your suspension.

aaronng
07-08-2006, 08:19 PM
There is no clunking or anything but I am thinking maybe the bushes are just really soft allowing all my arms etc to move incorrectly?
Cuz at say 120km/h+ if I start jerking the steering wheel from left to right continously, quickly, the car gets wobbly and it has no response at all. I was thinking it's just bushes flexing?
Did this just start happening only recently with the oil leak or from way before? Also, which bushes are you referring to? The front sway bushes? Why not pull them off to inspect? Becareful not to break them if they are oil damaged.

Jerking the wheel left and right and getting no response sounds like swaybars that are not stiff enough to complement your suspension.

spetz
07-08-2006, 11:31 PM
It started happening after the engine was swapped. But was not really bad at the time

Then the car (after oil had gone everywhere) had sat for 4 months doing nothing and after that it got really bad. I put my strut braces all round and that helped heaps

Also in the 4 months of it sitting the coilovers were changed from Fulcrum to Tein. Could this have done anything? The Tein has stiffer spring rates

iced
27-08-2006, 11:57 PM
does your steering rack have any freeplay.
possibly one or more bushes in the front steering setup are worns which is causing freeplay.

that can require you to put more steering work to keept he car straight because it is not as precise as you want it to be.

spetz
28-08-2006, 12:46 AM
I got it checked out by a suspension shop

THe front bushes were gone
But the biggest problem was a lot of the rear ones were well stuffed so my rear wheels kept changing toe degree while driving :)

yay!

string
01-09-2006, 10:29 PM
Did they do a "shock test" (or whatever excuse for a test they do)? Unresponsive steering and that "lag" you get when you turn, but takes a bit to dig can happen even with thick swaybars.

I have the crappest shocks in the world but quite a stiff roll rate, and I have possibly the worst steering response in the world also. New shocks are on the list, but not really a priority.

My 2c

spetz
05-09-2006, 11:49 PM
The shocks are fairly new with just a hanfull of km on them (tein SS coilovers)

Another thing that I just remembered is that I drove the car for about 25km with my front wheels toeing out heaps. Long story, but probably something like 30+ deg of toe out per wheel
I drove very slowly (had to get it to wheel aligner)

Could that have ruined anything?