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-50mm causes light steering and squeels like a pig - Help!

Posted: Mon Sep 01, 2003 12:04 pm
by david burton
I've recently lowered my mkIV 50mm. The steering has gone very light around the straight ahead position, and any g force round the bends causes the tyres to squeel.

I know I've gone the cheap way - i.e. springs only, but I wouldn't have thought that leaving out matched shocks would make it this bad.

Is re-tracking it going to solve the squeel (I guess the tyres point in the wrong direction now), and is the light steering due to the castor and camber angle change (it's non - power steering)

are there any ways i can solve this problem easily? i have very narrow tyres (155's)

any help would be greatly appreciated!

dave

Posted: Mon Sep 01, 2003 12:08 pm
by polo2k
id say for starters get the alighment re done

Posted: Mon Sep 01, 2003 1:53 pm
by Nelson_Wilbury
I'd say it might be the tyres.
I remember borrowing a 9n from the dealers with 165 tyres on (I'm lowered 30 mil with 195 low profile tyres) and that was constanly squealling around corners :D

Posted: Mon Sep 01, 2003 1:57 pm
by david burton
the odd thing is that the tyres were fine before, and cornered with a lot more force on them (I never got them squeeling, and I tried as hard as I could!).

something is upsetting it - time to get it tracked, although I am planning on putting 14 inchers on it with 185's which would mean tracking it twice!

Posted: Mon Sep 01, 2003 2:14 pm
by Nelson_Wilbury
david burton wrote:the odd thing is that the tyres were fine before, and cornered with a lot more force on them (I never got them squeeling, and I tried as hard as I could!).
Remember that dropping it that low would totally change the centre of gravity and behaviour of body roll. Its simple really, the thinner/higer profile tyre you have and the stiffer suspension will utimately affect the forces on the tyre. Put it this way, how many Lupo GTi's do you see with 155/70/R13 tyres :wink:

Posted: Mon Sep 01, 2003 3:52 pm
by dub envy
get the tracking seen to.

Posted: Wed Sep 03, 2003 9:12 pm
by Josh_PoloGTi
Not just the tracking...

Get a full Geometry alignment done:

Tracking
Camber (this is the very important bit)
Castor (if this can be changed?)

Good luck.

Oh, and get it done quick, or else you are likely to find your tyres will go through to the belts within a few weeks! :shock:

Posted: Wed Sep 03, 2003 9:33 pm
by polo2k
theres also the facty that a lowered car needs to be driven slightly differently as before the body roll caused by the cornering forces forces the outside tyres into the ground and therefore they gripped (due to the pressure between the tyre and the ground) however on a stiff suspension the car cannot roll so instrad of the body rolling and forcing a tyree into the ground the car tries to slide
this needs be compensated for in the driving style

Posted: Thu Sep 04, 2003 10:43 am
by Speedlaw
Just to tag along in this thread -

What Josh said: Can Castor be changed? They shop I went to reckoned it couldn't, but that didn't convince me too much really.

It's at + 2.04' and + 1.47' now, whereas the target is a max of + 1.50'...

Posted: Thu Sep 04, 2003 2:21 pm
by polo2k
castor is the angle (measured from vertical) of the axis through the shock its self. on vw`s rthis cannot be changed unless you remove the bottom arm and enlarge the 3 holes that the ball joint mounts into

Posted: Thu Sep 04, 2003 6:03 pm
by Speedlaw
Oh well...

Thanks for the knowledgeable reply Ash (as ever). Isn't it odd that my castor is different between left and right?

Posted: Thu Sep 04, 2003 10:35 pm
by polo2k
it can happen as the subframe moves etc

i thoght of a couple of examples of high castor:
motorbikes; if you look at a harly davidson (or any cruiser) the forks have a lot of rake which gives a bit of a dosile feel but makes things quite stable where as a super bike has very up right forks giving a very direct feel but twitchy handleing

cars; if you look at any big mercedes the shocks are quite angled where as most hatchbacks are fairly vertical this again is like the bikes with the merc haviong docile handleing, the effect of a big castor can also be seen when a bog sallon is on full lock as the wheels take on great amounts of camber i.e. instead of being like this I I they are like this / / which can also help with road handleing when body roll is large

Posted: Fri Sep 05, 2003 6:44 pm
by Speedlaw
Good explanation. It reminds me of my daredevil brother - he plays around with the castor on his stripped Gixer. Said the same thing, no castor means twitchy handling.

Image

Posted: Fri Sep 19, 2003 12:18 am
by david burton
Is getting the camber changed a big job? I heard that it was a VW garage thing....

Posted: Fri Sep 19, 2003 12:27 am
by KarlM
Most MOT stations should be able to do it.