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I've built a Mini that is similar in specification to a UK "Appendix K" racer for vintage racing here in the states. This includes:

10”x4.5" rose petal wheels & Dunlop R7 tires
stock "type" suspension
standard suspension pickup points
“Wet” upper control arms
Adjustable lower control arms
Adjustable tie rods
Adjustable camber/caster rear brackets
KAD rear sway bar, no front sway bar


My initial setup is as follows:
Distance from floor to “body seam” at the front = 7 3/4”
Distance from floor to “body seam” at the rear = 8 1/8”
Rear camber = negative 0.7 degrees
Front camber = negative 1.5 degrees
Front Toe Out = 1/32"
Rear Toe Out = 1/8"
Front shock setting = SPAX 3/4 hard
Rear Shock setting = SPAX 1/4 away from soft
Front Caster = +4.0 degrees
Front Tire Pressure = 22 psi ???
Rear Tire Pressure = 22 psi ???
Front Springs = HiLo's and Competition Donuts
Rear Springs = HiLo's and Competition Donuts

I don't really have any specific questions other than am I way out of line on anything, does everything look OK? I'm completely new to racing, so keep that in mind as well. A few things of particular concern:

1.) I have no reference on what the tire pressues should be (no one is using these tires in the states)…
2.) I’ve read that perhaps I should not use hard donuts on the rear?
3.) I’d like to get less toe out at the rear (I've heard one needs to have a lot of experience for rear toe out?), but I have no room for further adjustment (the radius arms hitting the brackets?)
4.) Some people have told me that lowered race Minis should run almost zero camber at front because they gain so much negative camber as the car rolls?

Any help, thoughts, or advice would be appreciated.

Thanks

hi Henry,

First, check the rulebook of the sanctioning body that will be running/organizing the events you intend to enter. There is an alphabet soup of racing orgs in the States, and they don't all use the same rules. Second, post your question on the vintageminiracing.com forum, state where you will be racing, and you will get helpful responses from local Mini racers. Third, if this is your first time on the track, set up the car to suit your driving style, don't try to set it up like the fastest Mini ever. You want to be as comfortable as possible for your first weekend of driving in competition. Fourth, make sure that wherever you race, that it is well supported with little cars like Minis, that they have a class that suits your car and that other cars of similar performance usually race with this sanctioning body. I have gone to vintage races and then discovered that I have the only little-engined car at the track that weekend, so I get stuck going out on track with a gaggle of Porsches and have to constantly try to keep out of everybody's way. If you do that, then there will be other Minis there, and they will help you with suspension settings and tire pressures. But failing that, call your tire supplier (Sasco?) and see what they recommend. If you get no recommendations, start with something like 24 front/22 rear and go run 5 laps, then pull in and check temps and tire pressures. Temps will give you camber clues, and see if your pressures are all coming up to the same, usually something like 30 to 32, adjust as necessary.

I think something is wrong with your rear toe, either the measurement or your brackets. You should be able to bring it back to zero (if that's what you want) by slotting the holes in the outer brackets.

Finally the statement "4.) Some people have told me that lowered race Minis should run almost zero camber at front because they gain so much negative camber as the car rolls?" is going to cause a lot of discussion when you talk to other racers. The guys racing on Hoosiers will tell you something different than the guys on Yokos. But I can tell you if you must keep the stock suspension pickup point locations that a slightly lowered Mini has decent camber curves, but the severely lowered Mini has awful camber curves.

Thanks for info, I'd just be doing some open track days and VSCCA events, I don't intend to be competitive, I would not have built the car the way I did if that was the case. It is a 1071 with twin H4s, just trying to have a bit of fun. I'm trying to determine if my initial settings are reasonable for a beginning driver, I don't really know what to expect from the car, so I just want to be sure I'm in the ballpark so it is not dangerous... then I can adjust from there.

OK, Henry. Well there is nothing in your description that sounds way way way off base. But a modern race Mini would be built with the main hoop further back than where they put it in my Mini, so the driver could be further back, and there would be more rear structure in the cage than in mine, modern rules would require a fuel cell where my car was raced with stock tanks, and on and on, so your weight distribution may be much different than mine... so all I am saying is that there will be some tuning/adjusting needed as you gain familiarity with what your car needs. I think your front toe is OK, I think your rear toe is excessive for a first-timer, I think your cambers will be OK to start but will need adjustment to get perfect. I think your wheels are too narrow for modern rubber. I think any old rubber cones that hold the car off the ground will be fine for its first time out, but eventually you will be drilling holes in the rear cones to try to soften them and adding a front sway bar. Have fun!

Hi,

at a glance. If you have lowered your car, do you use shorter shocks? They always need some place to work. Those Spax’s are not very effective. Rubber cones will better work together with gas pressurized dampers. For example the Koni’s from Nick Swift or Bilstein’s. The rear stabilizer depends on the limited slip diff you are using. Just try. Go to the circuit. Look for a 4th gear bend. Take it flat. Just leave the throttle control. If your mini will go directly inside the bend, you should change it.

Best regards.

You settings look OK as a starting point. Maybe a little less rear camber say half a degree as you need the back to be loose (use KAD rear camber brackets most do). I would use more front caster up to 7 degrees. Tyres front 36 rear 38 as a start point. Hard rubber cones all round. At least 1.5 degrees camber on the front. You should not use gas pressurised dampers on Appendix K cars. KAD rear bar is good and a limited slip diff is a must.

KJW wrote:You settings look OK as a starting point. Maybe a little less rear camber say half a degree as you need the back to be loose (use KAD rear camber brackets most do). I would use more front caster up to 7 degrees. Tyres front 36 rear 38 as a start point. Hard rubber cones all round. At least 1.5 degrees camber on the front. You should not use gas pressurised dampers on Appendix K cars. KAD rear bar is good and a limited slip diff is a must.

Thanks for the help.. Wow, 36 psi as a starting point for the Dunlops? What are the pressures when hot?