Norman
You are right, a properly adjusted 4 point harness will hold you in place more securely than a three point inertia reel system. One of the down sides of the comfort of Inertia Reel systems is that they are not usually as tight at the start of the impact. This can be due to position and movement of the occupant or loose clothing, thick jumpers, coats etc. This is why a lot of modern high scoring Euro NCAP cars are fitted with retractor, buckle or 3rd point pretensioner systems. These are designed to pull in the slack and tighten the belt before the occupant start to move forward in the impact.
The reason that more road cars are not fitted with 4 point belts as standard is comfort and I believe the regulation requires that the belt must be able to be buckled up using only one hand.
Chris
1700ss BRG/Yellow Stripe the only way to cruise
Edited by - Abbot on 30 May 2009 13:26:48