Ok I have decided to try my hand at building my own custom stretched chassis and I know there are a few of y'all on here that have done this so I'm reaching out to y'all for some advice!

First off would it be strong enough or advised to use 1.5 or 2.0 mm carbon fiber or should I use 1.5 , 2.0 or 2.5mm stainless steel
Second how much longer then stock should I make it I will be running a 3.3 at the track and mostly bashing I remember someone saying 1.5" extension is perfect??

Thanks for the help