I have an 07 MC non S and I wanted to know what upgrades I can add to it, besides an air intake, exhaust, etc. I want more speed but I'm not trying to get a ten second car haha

 

There is not much you can do to the non-S engine, pretty much just what you've listed. That being said for what you will spend on those things the reward will be very small.

Best bang for the buck IMHO would be money spent on the suspension. I'd start with a rear swaybar 19mm is a good size for a street car.

 

Common upgrades for any base cooper-

Weight reduction especially to wheels and tires.
lower the suspension, add an adjustable (3 hole) 19mm rear swaybar to reduce understeer
Upgrade tires to Max Summer or even Extreme Summer tires
While keeping weight down, upgrade to wider than OEM wheels (15" or 16" diam.).

Truth is there is not much power to be gained for the MC. You can do a little, you might look better and sound louder but it will be minimal gains.

Less weight requires less power to move from a stop or bring to a stop. Better stiffer suspension and lowered center of gravity will improve handling so you can corner faster even with no increase in power.

Moving to lighter wheels than OEM is always an improvement or if you want to stay with OEM wheels try the Imola or holey 15x5.5" wheel and put 205/55-15 tires on. Actually depending on your needs there are many sizes of tires that will fit the OEM 15" wheels-

175/65-15
185/65-15
195/60-15
205/55-15

will all work OK. But the wider the tire the better the cornering grip for Max or Extreme Summer tires. If you need tires you can run in the snow or cold then try Ultra High Performance All Season tires.

Personally I use OEM 15" wheels and UHPAS 195/60-15 tires for daily driving in my MCS and they work great. Very light and nimble with just enough grip for street use.

If absolute speed is that important to you, then you ought to get a Cooper S. Test drive one and find out.

 

You can get OBX headers and go cat-less.
As far as bolt-ons go, that's about it for a Non-S. The next thing to do is to decrease weight.

However, you could get: cams, injectors, head, port-polish, increase displacement, strengthen pistons, crank pulley, ecu-flash. But all that will cost you a very pretty penny. If you want power, buy an "S".

 

Are there any front strut tower bars that will fit the Justa? If it can be used with camber plates that would be even better. All the ones I've been able to find seem to be only for the S.

What about engine tunes? I realize that you won't get much (if any) power this way, but I'd be interested in a higher rev limiter. Can this be done safely?

 

I don't think the front strut tower bars are needed on that model year, and an engine tune will not result in anything, higher revs would just break the valve train and the torque party is over at just 5k anyway. Enjoy your cornering speed and your awesome gas mileage over the "S" turbo, as well as far less repair worries. Oh, and I see you live almost live in the Arctic Circle, might pass on the Extreme Summer tires then,....

I think the torque insert from NW is a great option to consider on the manual shift, and follow it up with a re-calibration of the electronic "gas" pedal. A BM clutch stop makes shifting sweeter, especially combined with a full brake/clutch fluid flush, (get the shifter cable greased as well).

Since I had the "Sport" stainless steel exhaust from the factory, at 50k miles the muffler has worn in well and I am happy with the result as is, but I have done all the other mods above, the lightweight wheels and sticky non-runflat tires appreciated very much. Once you open the breathing with a better filter, and modding/replacing the intake pipes, there is nothing much more to be done on the engine - it is what it is. Invest in suspension parts to help you carry corner speed and and your technique. A couple of pounds savings can be had by dropping the spare tire off, but the "Justa" is already lighter than the "S" anyway.

If you can get the chance, take it on a race track and you will see the "Justa" is not a slouch on a tight course in experienced hands!

 

The best mod:

Just drive it. Especially somewhere with lots of corners. Autocross it, or if you can (and have fresh brakes and relatively fresh tires) take it out to the Big Track.

Enjoy the car for what it already offers.

 

Take a look at Outmotoring.com, I installed a "Snorkel", it did give me a stiffer pedal and a more GoKart feel, a definite noticable cabin sound, not as throaty as the stock airbox, sounds more aggresive. I'm still very happy I did this mod. been almost a year now!!

 

By "Snorkel" do you mean an AIR VIP2 or some other mod? I searched Outmotoring for that term and came-up empty...

 

Looks lije Outmotoring doesn't stock them anymore, the almighty Google shows them on MiniMania's site though!!

 

Ah...thanks, I found it on Mini Mania! Looks like the VIP mod that I have already installed. You're right (comment in earlier post) that the Snorkle has a great sound! About two weeks ago with temps in the single digits, it reeeally growled!