Originally Posted by bryce
both turbo's are the same size. if i remember correctly, they're k03's. you can find a spec sheet for the turbos over on e90post. it's pretty technical but it gives you an idea what the turbo's are rated for and their peak efficiency. they are not a sequential setup like your co-worker is talking about, they're the exact same. one turbo for 3 cylinders each.
i wouldn't say 1-2 cars, but it's noticebale. the biggest gains come in consistent performance, where teh aftermarket intercooler doesn't heat soak and keeps IAT's cool enough to avoid as much IAT decay.
as far as the weight, i look at that as a good thing. the heavier the intercooler, the more heat it can dissapate. there may be a package deal for the hpf intercooler and charge pipe, who knows. i live in texas, and it gets very hot and humid here. i was happy to improve the cooling capacity of the engine and allow for more consistant power.
it should be noted that an oil catch can should be installed when you do the intercooler. oil blow by can coat your charge pipe and intercooler with oil, lessening the efficiency. i went with the ar design catch can, great buy IMO
Thanks for the info mate. I looked into getting a catch-can some time ago but the vendor never followed through with sending me the installation instructions. They're bloody expensive too!