Understeer at very low speeds but amazing grip at high speeds?

[benjamincalleja]

Hey guys...weird things happening with my new OEM front suspension for my 89MY turbo.  It used to have AVO coilovers front and rear and the front was lowered so much you couldnt even see a gap between the arch and the front tires.  I never really experienced good handling until now - i replaced the fronts with the OEM units (car now riding a bit front-high) but it has tranformed the handling (even though all the bushes are nearly dead).  Weird thing is though, the high speed handling is now really confidence inspiring but ive noticed that, especially in the wet, my citroen c4 has more grip going around corners at low speed!  At roundabouts doing say 40km/h the esprit understeers terribly!  In the dry it still understeers but not as much, need to be doing say 50 or 60 round a roundabout to make it do it.  The same speeds in the dry in the C4 are effortless!  Is this a design thing, is the esprit meant to have loads of grip at high speeds at the expense of low speed grip?

[Vulcan Grey]

By raising the car, now you need to redo the alignment. To much toe-in in the front can cause understeer. If the car was aligned for the previous height, and now you raised it, it will have increased toe-in if you haven't aligned it yet.

[rogerch]

I might suggest you've done it in the wrong order, you need to replace the bushes, I'd recommend poly, but you can't draw any conclusions until the geometry is right, including as Travis says, alignment. (remember the ARB mounts too).

Edited December 21, 2014 by Roger the Dodger

[Vulcan Grey]

btw, the stock Lotus 89 spec was for toe-in, which really isn't good.  Later they went with a spec that allowed some toe-out, which some people may not like, but I prefer it.  Go with the later spec for front toe IMO.

[rogerch]

I tend to think it's down to driver preference. Toe out was introduced negate understeer so it might solve Benjamin' immediate issue, But I'm not a fan I find it reduces the "smoothness" of transition from brakes to power, as a left foot braker I may been on the power before I'm completely off the brakes.

I run a "smig" toe in, allowing for bearings and bushes I'm probably tacking parallel.

I'm still maintaining you can't set it up until all the bushes are done. Also you noted the front was sitting higher which may well mean you have transferred weight to the rear wheels, which can, usually does promote understeer.