Hello S14.net members. I'm Robbie, manager of Piper Motorsport. I heard about this website from BMW customers of ours and figured I'd stop by and share a new project we are currently working on.
We started with a 1988 BMW M3. We built a custom chassis for the M3 body on a chassis jig using all new 2007 BMW E90 front/rear subframes and components including E90 differential and all the E90 suspension as well. To power the new chassis is a 2007 M5 V10 engine and trans. We built the chassis with the motor and trans positioned in the ideal location for the cars weight balance. The subframe and suspension components were assembled on the chassis jig to fit within the factory E30 M3 tub. The car will be equipped with E90 MOTON Club Sport suspension, E90 Brembo Gran Turismo brake kit (large) and MOTEC engine management.
I have plenty more information on this build, which is still in progress, on the car domain page I've created which is updated a few times a week. Once I have some more time I will also upload all the info onto our website. Feel free to ask any questions!