i had to figure this out when i tried to put three webers on my land cruiser. i would be happy to help, but i need to get home and get all my equations. just for starters though, you should go to twm, do a search on google. they are resonable and already have bimmer stuff. the throttle bodies for the bike probably won't work on the car even if you set the runner lengths up properly. i dont think that they provide near enough air. i will need to know a lot about your engine if i am able to help you. when i said tried, i have the intake made for my truck, but don't have $1220.00 to buy three carbs, which i then will have to tune. my intake looks something like the one in the pic, but has three carbs on one side. really this is an easy process if you know math and can figure out acoustics. i taught myself by reading 20 different books and would be glad to simplify things for you. tomarrow i will be back on the board as my home doesn't have internet. get all the specs you can about your engine have them ready around 6-8pm. next time i'm on i'll let you know what all info i need. later ggood luck.