The real question I have is whether or not it would be possible to retrofit side curtain airbags into the w126 body. I understand you would also need a lateral crash sensor, powered independantly, and made sure you got a model, (maybe from the c-class or maybe BMW's early tubular HPS)that is able to fit. Judging from my experience at a few BMW junk yards, the late 90's HPS system is quite compact and can possible be made to fit with minimal bulging of the headliner and A-pillar trim in that area.

I am curious because:

1) It would be a fun project and most of the parts (I think) I could get cheeply from a yard here in Phoenix.

2) Side curtain airbags are one of the major and most important safety innovations in automobiles of the last 20 years. Only ABS and Stability Control can come close in its statistically proven ability to prevent serious injuries.

Any thoughts on wether it is possible and what problems I might have?

I don't think this will be possible, there's no space between the interior trim and the body. Plus the shape of the airbag is designed to fit the car, they aren't universal.

You might be better off trying to retrofit seat mounted thorax airbags. Those seem to be more "standard".

A bigger problem is the calibration of the crash sensors. You can't just take the whole system from a Jetta and plunk it into an S Class. I'd be worried the system would fire too early or too late, and there's no easy way to test it.

-J

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