Twinz said:
Go for IC and water/meth since you drag race.
I would do away with the Mr 5 mod. That mod was an idea that OB from chiplogic and I discussed already during 2007 for the X35 platform (actually OBs idea) then we saw Mr 5 posting pix on e90 which was simmilar to our discussion...however, we realised after testing that the stock box (with K&N filter) or the DCI's will work best or a custom made CAI and I think OB leaned more towards the latter...I prefer the DCI's.
However, I am not saying the Mr5's mod is not working...just that it is unnecessary compared to available options.
A big factor also to take into account is the cost of replacing the airbox which at the time was in the region of R8500.
Hubbly, the heat soak you are experiencing is not related to the intake temperatures. Are your oil temperatures going high and you getting boost decay?
Dropping intake temps does help to a certain extent either using methanol which is the most affective or by adding a intercooler. The advantage varies between a few cars relative to how efficient your cooling system is. I have started to believe that carbon build up on the valves also affect cooling efficiency so this will be affected with how much mileage is on your car.
Running the car slightly richer also makes a difference.
