325iSE_mams said:
I think that's the reality one has to face. i've done research, spoke to Rob Green & Steve Auto and the only way to achive max power is by Turbo / supercharge conversion which will cost a good +/- 90k. # not worth it.
now looking at buying a 335i
You looking in the wrong places mate.
I had a 323i, which has a 2.5 litre engine. I supercharged that through a company called Project Shift. Cost nowhere near the price RGM charges and made more power than what RGM said they would make.
Give Project Shift a call and find out what can be done for your car, but from what I have seen, I doubt the e90 has a supercharger kit available.
I am now supercharging my M3 and once again, its costing me nowhere near what they quote. I would never take my car to RGM. Complete rip offs. You can import a supercharger kit from VF engineering or ESS for R40k (e46 models) and install it yourself. It really is easy. Just cause RGM are well known and people drop their name like its hot, doesn't meant they are necessarily the best and the only guys able to do the job.
Many guys can vouch for the supercharged 323i that I had.
But as the guys stated, without spending massive amounts of money in regards to an entire engine rebuild, you won't get much out of an NA car. You will need some serious Head Work, flow the heads, bigger cams, over sized valves, throttle bodies, bigger intake and bigger fuel injectors. A remap then will be required and exhaust will need to be modded to allow better flow. That should give you a great increase in power, but don't expect to be destroying sports cars. You could also look at lightweight flywheels to allow the car to rev up more freely. Faster revs means you get on the power quicker.
If that's not enough, you could get a stroker kit for your car. That is where you will get most power, but then you are spending big money. By then, you would have come full circle and you will basically have a race engine that is hard to drive, it will be uncomfortable, and loud. So... How long is a piece of string?
How much power do you want?