As much as I love this car, the handling has never been up to spec in my opinion. I’m well aware than I want to have my cake and eat it too, as it is sitting very low for a Sierra, and the simple suspension on a Sierra isn’t hugely happy with being decked! Up front the roll centre is knocked out, and arms start to sit at awkward angles. This has been partially sorted so far with 3dr hubs and offset track rod ends. The self centering both on drift and whilst manoeuvring is still dismal, (but that’s a task which will be once again being tackled very soon). At the rear the back end adds lots of negative camber when lowered. The trickier and more detrimental downside to the trailing arm design is the quite extreme toe in which happens when lowered. This does create extra directional stability as is intended, but it also makes everything much snappier when the limits of traction are reached. This can be corrected with an adjustable beam like Mark at MC Fabrications provides. With the toe set at zero there will no longer be an overt rear bias to the car’s grip, and therefore much less chance of understeer. A more advanced car’s chassis will either already have adjusters built in, or automatically self-correct on compression. So with this MC 6-degree beam the old Sierra is at least starting to catch up!
With the rear beam fully powdercoated it was time to get MJ Racing to fit it. And whilst in there the old and slightly suspect looking beam mounting bushes were replaced for some far superior Powerflex bushes. Of course Powerflex is my first go to choice for tightening up a chassis, and in this case they had the perfect option for us me again. The ‘Black Series’ is a no nonsense seriously heavy duty track spec range, and perfect for the Cossie which is now mostly polybushed apart from a select few uprated bushes! I was warned that they can be tricky to fit, but I didn’t hear one complaint from MJ Racing about this, so either they are masters of fitting awkward stuff, or they really weren’t that bad. I’m suspecting somewhere in the middle!
Also in the Chassis department this month has been a full refurb of the GAZ Cold coilovers. Around five years, several thousand miles (with a good few on track) finally saw one of the front shocks spring a leak. Not bad going really considering the use the car has had. The once chrome finished bodies were also now more of a ‘Titanic brown’ too, but I knew GAZ would easily sort them out.
When they arrived back they looked almost brand new. The chrome was replaced with a more durable black finish, in line with the rest of their current range. And the internals checked and repaired/replaced where necessary. I have no doubt that they’ll perform as good as they look too!
MC Fabrication – www.facebook.com/Mcummings27
Powerflex – www.powerflex.co.uk
Gaz Shocks – www.gazshocks.com