[BMW135pls]

Firstly, I don't think my launch performance is bad at ALL, still way faster than most cars on the road and I'm ok with that. The question I have is why hasn't my 0-60 time shortened with the mods I've put in and after learning how to launch it better?

On a complete stock car when I got it last year, I clocked 5s 0-60 time. At the time I was just putting it into DS and ogreslamming the throttle. The car had bald runflats on it at the time, and the suspension was stock so I was bucking and snaking around the whole time. Since then, I've put in a JB4 on map 5, which doubles the boost pressure to 16lbs. AA exhaust/dps which are pretty wide open (stock midpipe still installed). M RSFB bushings, which tamed the back end so that launching no longer causes the bucking/snaking. And brand new Michelin 225/255 PSS tires, which widen the contact patch and really help to put the power down. Now I am also launching in 2nd using mild brake boosting to between 1.5k-2.2k RPMs. 0-60 times are completely unchanged at 5s absolutely flat.

I know the only "performance" related mod has been the JB4 upping the boost pressure and all, but it all helps in its own way. Should I expect to see the time go below 5s with future mods, or is that figure indicative of a limitation of the frame? Am I launching wrong? Any thoughts?