BASIC MODIFICATIONS WHICH ANYONE CAN PERFORM

Exhausts, Inlets and Air Filters


The standard exhaust and manifold on a Mini isn't exactly the most powerful design but then again the car wasn't designed with power in mind.

I'll do a quick example of the path of the air and fuel, as it goes through the car and out the other end.

 
Air Filter
The air filter is the start of the air flow. Nowadays reasonable quality filters are place in, but the older cars, especially if never replaced, one can see a drastic affect in performance. Simply changing the filter can raise your Mini's BHP considerably. Fitting a performance filter (K&N, Pipercross) will make a noticeable difference at a low price and takes very little time.

Inlet Manifold
Designed for economy this can also be replaced easily. Many after-market manifolds are available nowadays, which flow the air/petrol mixture much faster than the traditional one.

Exhaust Manifold
Yet once more, not designed for power. The best type you can aim at is an LCB (Long Center Branch). Basically this has a longer center branch so that when all the exhaust gases come together, it is cooler, better distributed and therefore less dense. More exhaust can be pushed through and so the engine can pull in more air/petrol mixture faster.

Exhaust Systems
Again the standard system sucks. To compliment with an LCB manifold you would require a largebore exhaust system. There are may after-market systems available which are ready tuned. Don't be tempted to put on some 4 inch drainpipe system as you'll end up with even less power. The maximum diameter should not exceed 1.75 inches for engines up to 125 BHP.