Suspension Geometry Set-up

JC · Post by JC » Fri Nov 17, 2006 11:30 am

Why (bearing in mind the GTO is 4WD and 4WS) when having the castor, camber and alignment set-up do they not have you sit in the car to do it... surely the weight of the occupant(s) has a bearing on the geometry?

JC

duncan · Post by **duncan** » Fri Nov 17, 2006 12:09 pm

Good question - I think they assume a certain amount of dynamic movement and build that into the settings.

Zak's (Mocom Racing) new set up with give geometry settings through a range of suspension travel so will get rid of this guesswork - cant wait for it to be installed and then we can arrange a group Geometry set-up session down there

Post by **Ben** » Fri Nov 17, 2006 12:11 pm

Is there a single perfect setup for a car? ... with regards suspension settings I guess perfect is dependant on the driver's needs.

Is geometry the same thing or more about making sure the components are set up correctly in the first place?.

duncan · Post by **duncan** » Fri Nov 17, 2006 12:24 pm

I think that settings are very driver dependant but as none of us are test drivers and able to distinguish (or communicate) what effect each .1 degree of camber or castor angle makes, we have to go with other people's recommendations.

There are various settings for imprezas on the go around the UK, I am sure that Zen have a completely different set up to TSL or Powerstation or even Prodrive.

There are also variants dependant on the useage of the vehicle ie fast road, track, drag, group N rally etc.

Mine was set up by TSL but I will be reviewing the geometry to see if I can get more track orientated settings at the start of next season and probably playing with them through the year. Adjustable top mounts will be on the shopping list

Pike · Post by **Pike** » Fri Nov 17, 2006 1:20 pm

murano3 wrote:Is there a single perfect setup for a car? ... with regards suspension settings I guess perfect is dependant on the driver's needs.

Is geometry the same thing or more about making sure the components are set up correctly in the first place?.

Its both in my view murano3

You can alter a vehicles handling charecteristics by adjusting camber,caster toe etc so which settings you use would again depend on the driver's needs/style.
I've always set car's up with the driver in the car & 50% fuel on board. It is suprising how much the cross weight changes with the added mass of the driver, and how much the geometry is effected
I realise that when working on a customer's car they may not always be present to be in the car when it is being setup.

323ian · Post by **323ian** » Fri Nov 17, 2006 4:42 pm

Surely unles you have special parts installed you can not adjust camber and caster on a stock car with say some coilovers?

sleepyhead · Post by **sleepyhead** » Wed Dec 20, 2006 3:59 pm

Stock mx5 allows you to adjust castor, camber and toe. Not 100% sure on other makes/models.

duncan · Post by **duncan** » Wed Dec 20, 2006 4:12 pm

castor and camber were both adjusted on my standard set up. There just isnt a lot of adjustment.

Andy916 · Post by **Andy916** » Wed Apr 18, 2007 4:52 pm

dynamix wrote:Mine was set up by TSL but I will be reviewing the geometry to see if I can get more track orientated settings at the start of next season and probably playing with them through the year. Adjustable top mounts will be on the shopping list

Mine was set-up by TSL last time, but to custom settings a bit more track-oriented than their usual ones. Only downside is that it's not quite so relaxing as before on a motorway (minimal toe, basically).

I trawled the 22b/sn/nasioc and compiled recommendations before trying different settings myself. Have tried 2 lots of camber/toe settings so far, and various ride heights. Very happy to share these next time I see you Dunc.

Will be very interested to see Zak's new setup and get mine checked/adjusted there this year.

Adj topmounts defintely recommended. They came as standard with my coilovers and, the way they're fitted, I can get extra camber+caster at a trackday, accurately with minimal effort. Get adj rear bar (from Whiteline) too, this allows effective control of the car's neutrality. With 22mm rear bar on max, mine is just about right in the dry (I reckon) but slightly twitchy in the wet (spun once in a damp session at Snett the other month).

cheers
Andy

duncan · Post by **duncan** » Wed Apr 18, 2007 8:11 pm

Zaks settings really work well here - turn in is beautiful :thumb:

Tyre temps show some good use with slightly hotter on the insides due to the negative camber so it is using what it has well rather than rolling over the tyres.

Have dropped the pressures down 2psi today and that has made a nice difference too