Stock M3 E46 will not survive under a turbo project. Even the standard E46 M3 suffers. We know about lots of engine failures.
You need different pistons and connecting rods.
Pistons and connecting rods must be forged and lighter.
The final software has to be excellent.
Sound performance is a very good tuning company, however they modify Supras. BMW is a different car, and I know what I am talking about.
I recommend you to supercharger the E46 and make maximum 450 hp, meanwhile change the connecting rods,
Or change both the pistons and the conecting rods and turbocharge. There are lots of details, be careful. If you need more info, email us at
info@da-motorsport.com
Mert