Chassis Datum Points
 

I am at the start of a long journey to build a 908/917 inspired narrow bodied pre-73 LWB hot rod. The chassis will be a tubular steel space frame covered with carbon fibre bodywork and with a mid-mounted air cooled flat engine. In short a very track focused road legal sleeper.

I have a Porsche 930 I can take measurements from which I think shares the same basic shell as a pre-73 with the exception of wider wheel arches, different bumpers and front wings.

What I would like to do is jack this car up level and using a drop line in various positions to mark out and draw on to MDF a full scale silhouette of the floor pan etc so I can workout what are my limits for fitting into outside body shape a chassis similar to the one below which I am part way through designing.

http://forums.pelicanparts.com/uploa...1301784716.jpg

http://forums.pelicanparts.com/uploa...1301784779.jpg

When checking the straightness of a 911 chassis what are the best datum/jig points to use? As I would like to create a centreline for reference.

What would be good reference edge/flat to check I have the car level? [img]

Would the dimensions in the "Body" section of the factory shop manuals help?

There are lots of different dimensions to various jig points there.