Green Machine update

Some time back I mentioned that Green Machine can, on occasions, be a bit of a handful.  Even at quite low speeds the car will tend to chase any road imperfections and if you push it a bit this twitchiness only increases – take the old girl to her outer limits and come off the power and you’ll be wrestling to keep her even close to straight and you could end up going anywhere. The problem is a thing called tramlining and it’s one that’s common to most Z3s.

Now without getting too technical, this idiosyncrasy is caused by several things with chassis flex being a major contributor and, not so great steering/suspension bushes also playing a part as well.

Checking out the Beemer forums advise varies, but the general recommendation is do all you can to stiffen up the front end………….. so that’s what I’ve done.

Searching through ebay, I got a great deal on a really nice polished ally front strut brace. When fitted, the brace ties the two front suspensions turrets together and eliminates the possibility of lateral flexing in these two components. The added benefit is it’s a really cool bit of kit and with the bonnet up the car looks all mean and track ready.(or boy racer, depending on your point of view)

Z3 Strut brace 2 (3)

The next stage was to tweak the steering. Powerflex do a superb range of polybushes, these are solid and much harder than the originals and when in place eliminate the inherent sloppiness of the softer factory fit rubber versions.

I decided to replace the lower wishbone bushes first with a view to seeing how that did before investing time and dosh in any further improvements.

Ok so now for the road test. Well I’ve read varying reports on others success or not so successful improvement so I took Green Machine out with some trepidation. I did my first  run on a couple of bits of road that have given me problems in the past and it seemed to go pretty well, but the acid test was on particularly nasty bit of fast downhill dual carriageway that ends in a roundabout, not far from where I live.

I gave the old lady a fair bit of welly down the dual bit and rather than disclose the actual speed in print, suffice to say it was on the fast side of quick. As I approached the roundabout, foot off the gas, stamp on the brakes and grip the wheel ready for the sleigh ride…but no, in fact straight as a die (ish) and no histrionics at all – well almost none, I mean she’s still not perfect but man, she’s a hell of an improvement on before.

Result, as I think we chaps say

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