49 replies to this topic

[Cooperman]

Of course they are. It lowers the centre of gravity to enable maximum corning speed and minimise body roll to keep the tyres as flat as possible on the track. They drive on totally smooth roads and the suspension is lowered properly by actually raising the sub-frame. If I were building a race car I would get it as low as I could by modifying the front sub-frame installation to maintain suspension geometry, I would fit plastic windows, strip out all the soundproofing and lower the C of G as much as possible. I would also fit a rear anti-roll bar and re-set the rear geometry to give zero toe-in to enable me to get back hard on the power as early in the corner without understeering. I would fit an LSD and a very low final drive to enable max revs to be pulled on the longest straight doing the final gearing with straight-cut drop gears.

 

I have driven many lowered race Minis on test over the years and on totally smooth surfaces the amount of suspension travel is not an issue.

 

But you wouldn't want to go out shopping in a race car, you wouldn't want to go racing in a rally car and you wouldn't want to go rallying in a shopping car. You could, however, go shopping in a rally car and I sometimes do.

[HUBBA.HUBBA]

Out of interest, how do you go about raising the subframes.

[Cooperman]

I've never done it myself as a lot of the cars I've built have been rally cars and they are normally raised a bit from standard.

However, to raise the front sub-frame you need to modify the underside of the cross-member against which the sub-frame towers sit by cutting and welding the platform a bit higher up.

Then the front panel needs to be modified to match the higher mountings on the sub-frame. The rear mountings can be modified to pick up the bulkhead or, if a later car, new brackets can be made up to mount the sub-frame in the same way as the Mk.1 & Mk.2 frames were mounted which is much better than the later cars.

There will be other bits & pieces to be done, for example the steering rack will need to be slightly higher on the bulkhead, engine steadies need modification and the carbs will be higher which may make bonnet mods needed.

If you want to do this work out the basics before starting and measure everything carefully. It should be possible to raise the sub-frame around 1" or more and normal lowering within safe limits for the geometry will lower it a bit more, then it will be track-suitable.

[HUBBA.HUBBA]

Sounds like a lot of work to me. Think i'll stick with my adjustable coil overs

[Cooperman]

It's certainly a heck of a lot of work. But if you are building a race car then it will be completely stripped down to begin with so access to the body for cutting away and welding is then easy.

Also, if that was done on a road car there could be implications in terms of needing an IVA inspection as the monocoque, i.e. body structure, would have been modified and that's no longer allowed.

It's the same for any competition car. I just sent a build sheet for a Historic rally Mini to one of our members on here and it is 4 full pages long. Again that assumes starting from a fully stripped shell, then lots of seam welding and special strengthening during the build phase. You not only get problems when a car is lowered, but also when raised. As the car is raised the front wheels go towards more positive camber and longer lower arms are needed.  I usually raise my rally cars by about 1/2" for road events, a bit more for rough forest rallies and to standard for generally smooth tarmac events - but 'smooth' is, of course, a relative term and the cars still get all 4 wheels off the ground over big 'yumps'. To me rallying has always been more of a challenge than track driving.