ok, ben here, mels husband.
im now building my forth mr2 turbo project so i have some info you might like.
firstly the chip is a good thing, but only if its setup to suit your current state of tune. i tuned my last mr2 from 220bhp standard to approx 280 using some of the following:
exhaust - you need to replace the catalytic converter for a de-cat such as the ones on ebay - expect to pay between 75 and 150 quid. then you need a good 3 inch exhaust, i had a 5zigen single exit one. because all of the exit from the engine is under serious pressure 3" is the minimum you should go for, and expect it to be louder as a by-product. i prefer single exit but there are many options. the owners club reccommends mongoose exhausts - expect to pay 300 ish quid.
air intake - part one - filters - you need to remove all of the air box and put an aftermarket air filter as close to the side vent in the left side engine bay as possible. but remember that you dont want water to get into it so dont try and put it too low. any filter will do, its about personal preferrance. i dont like foam filters as they can degenerate and breakup, but thats only personal. the stainless steel ones make a great whistling sound too.
air intake - part two - removing the mass air flow sensor (the metal box beside the air filter) this can only be done when using some kind of different ecu module. it means changing the sensor to something that measures fuel mixture in the exhaust rather than the metal box. that metal box stops a lot of performance and if you do this mod expect to pay around a grand and gain about 50 bhp. only worth doing after the other stuff.
ancilleries (sorry about spelling) - removing the air con pump from the engine will take out weight and remove one of the dragging belts from the engine, improving fuel economy and increaseing power - free.
doing the above means you can remove the aircon radiator from in front of the cooling radiator which means more cool air will run through keeping your running temp down, always handy.
increasing boost pressure. the mr2 turbo is set to around 7psi as standard safety features. you can increase the boost pressure to around 13psi reasonabley safely (most people do not reccommend anything higher than a bar). in order to do this you deffinately need to fit a boost pressure gauge so you can see what you are doing. both items you can get from ebay for under 100 quid and you can fit them yourself.
that should get you started
