To start off I've been racing oval tracks off and on the past 20+ years. Recently I've been thinking of building a 4 cyl car to run at my local track. Almost all the cars in the class are Saturn Ion. I had the thought of running a Mini in that class, they don't allow any turbo or superchargers in the class tho.
So the other day searching craigslist I found a '04 Mini, 5 speed with a rod knock for $1000. I ended up getting the car for $700 and it's actually in pretty nice shap. I can get a used motor from LKQ for $550. My plan is to strip the car of all the glass and install lexan windshield, quarter windos. Completely gutting the interior including dash and installing a 8 point stock car type cage with aluminum seat. You are supposed to only use oem suspension parts but you can cut up to 2 coils off each spring and there is no ride hight rule. You are allowed to remove the muffler and converter.
My question is to the expert Mini guys on here is what would you do to this car? Would running straight exhaust hurt performance or help it? I know if it was a carborated motor I could tune it to run with straight exhaust but I'm not sure with the computer. Is there a tuner available for the base Mini, I've seen them for the Cooper S but not the base 4 cyl model.

 

Well I don't know anything about this, but there's a dirt oval in my town, so I'd love to see the kind of progress you make with this project!

 

Interesting project.
If you keep the engine's CPU, O2 sensor and other engine management stuff you should be ok with a straight exhaust.

Can you make any other exhaust changes such as adding a header? And adding a good CAI, is that allowed?

Light weight wheels and tires are a must. Except for the MINI's holies (15" wheel with 5 big holes) MINI wheels all weigh a ton.

The MINI needs front camber. Removing 2" off the springs will help with that. On the Gen 1 MINIs there isn't much else you can do with the stock suspension in the front. For the rear, there is some camber adjustment you can make and it might be worth removing a bit of it from the stock settings.

Are MINI factory option suspension parts allowed? If they are get your hands on the JCW springs and rear sway bar. They are both stiffer than what you get in a base MINI.

Dump the MINI shocks, if you are allowed; they are crap. Bilstein B8s (non adjustable) or Koni Sports (adjustable) are good choices for a lowered car. If you have to run stock MINI parts, you will want the JCW shocks.

Can't help with the engine tuning. Maybe someone like Way Motors could help with suggestions there.

Hope that helps.

 

Thanks for the tips, rules say exhaust must remain unaltered but may remove converter and muffler. There is nothing in the rules saying you can't use a cold air intake so that should be a go.
The wheels can be steel or aluminum 14"-16" no wider than 7". The car has steel 15" wheels on it now, I've been keeping my eye on Craigslist for some aluminum wheels. Everyone in that class runs Hoosier 850 race tires.
The suspension is supposed to be oem and unaltered except for cutting of coils and spring rubbers are allowed. With being the only Mini I don't believe anyone would notice if it had a bigger sway bar or better shocks as long as they don't look that different than oem. With no ride hight rule I plan on getting in down as low as possible without it bottoming out on the track.

 

Kosei makes a nice, very light wheel, 15" and 7" wide. The MINI likes wheels in the offset range of 35 to 40 mm.

As for suspension I guess it depends on the actual definition of "OEM". The full JCW sports suspension was an available option for the Base Cooper, which would make OEM in one sense. If OEM means what the car came with, with no options, then you are stuck. That would be your decision.

SCCA allows any shocks even in their stock class. I would suggest checking the rules for those unless you know for sure what they say.

There are threads on here that discuss a vibration in the drive train that occurred in some, but not all, MINIs that were lowered by about 2" or more. Not sure if it was damaging or not or if you care about it in the type of racing you will be doing.

 

tudorfritz, what are you planning on doing for the key and related module? I want to race one of these too, and ditch all the electronics that aren't needed as well as any weight I can. running into a headache with the key and programming.

 

The wiring on these cars is definitely a challenge when making a race car out of them. I have the car completely gutted now, all the glass, interior, dashboard, and lights are all gone. Every time I would unplug something I would start the car to make sure it still runs. The rules state that you have to use the oem steering column at the track I'm gonna be racing at. I'm keeping the original tach on the coulmn but I removed the trim, turn signal switch, and steering wheel. I'm just gonna leave the original ignition switch and key in the coulmn.

 

Where are you running Tudorfritz? I race at an IMCA track, that's really all there is around here. But inside of an hour and 15min I can run wed, fri, sat or sun all with the same rules.
I've got to read those rules again too. That column thing might be for me too...

 

I'll be running it at Lancaster Speedway it's just outside of Buffalo NY, it's about 10 minutes from my house. The track is a 5/8 mile paved oval with a flat 1/4 mile oval in the inside that they run the 4 cyl cars and TQ midgets.

 

 

Got the cage started, still got a few more bars to put in and mount the seat.

 

Looks great so far! Keep us posted. I watched one at the salvage auction on the 5th, pulled $250 plus $180 in fees, plus $80 for fuel and $200 for key/lock/EWS/ECU replacement would have brought it to $710 for the start of a racer. Also red.

Do you have a set of scales to see what it weights when you are done?
Will you run 15" or 16" tires? Is it a spec tire or wide open?

 

yes I have scales to weigh it, as soon as the cage is done I'll see what it weighs. It was little over 2400# before I started taking it apart. I have 15" wheels on it and gonna stay with them. At the track I'm gonna run at you can run any dot tire or your allowed to run Hoosier 850 race tires. It would be kind of dumb not to run the Hoosiers, that's what everyone runs in that class.

 

what are you going to do with the sunroof hole?

are you building the cage yourself?

 

Yes,I'm doing the cage myself. I'm gonna pop rivet a aluminum panel on the roof and paint it white. I figure the tech guys might say something if I leave the hole in the roof plus I need a place to put the roof number.

 

 

Wow!, That's some good looking work done on that. Nice job!

 

 

Looks great, so far so good...

Motor On!

 

 

This is so cool! The car looks amazing. Congrats on your finish, wow!

 

Congrats on the finish the first time out.

If you are looking for handling improvements the JCW front and rear sway bar should be an option available to you. While “everyone” says “bigger rear SB, smaller front SB” a larger front sway bar will help to maintain good front camber. To compensate for the larger front bar, trailbrake or coast into the turns and don’t get on the gas until after the apex. If you get on the gas before the apex the car will push and it means you are over-braking before the turn. The JCW springs would also be a plus.

 

 

If it helps, here are the sway bar sizes for the MINIs:
JCW - rear 18.5 mm and front 24
Optional Sports Suspension - rear 18 mm, front 23.5 mm
S - rear 17 mm, front 22.5 mm
Base Cooper - rear 16 mm, 21.5 mm

Remember that the stiffness of the sway bar goes up by the radius to the fourth power. So a 1 mm increase is sizable.

BTW - I have a 23.5 mm sports suspension front sway bar you can have if you want to come over to Watkins Glen sometime when I am there.