Haynes Roadster Bonnet

The looks of this car have always been important.

The white line in the above drawing (bonnet centre line) represents the lowest a Haynes Roadster bonnet could be made without a bonnet bulge.

Haynes Roadster

I don’t want this car to have its’ nose stuck up in the air.

This chassis is basically a ‘442’. It’s 4″ longer, 4″ wider and 2″ taller. That means that a standard bonnet already sits very high relative to the ground.

In the above shot, the nose-cone has been tilted down slightly toward the front. On a standard chassis the bottom of the nose-cone would line up with the lower chassis rail.

In order to get a better side profile the top of the bonnet will need curvature. Not being a master of the English Wheel, an aluminium bonnet is out of the question.

Therefore, on this car the bonnet may need to be fibreglass or have a bonnet bulge.

There are several options:

  • a bonnet bulge
  • a fibreglass with front to rear curvature.
  • extending the bottom edge of the nose-cone opening downward to give a larger grill area.
  • dropping the nose-cone 2″ over the chassis
  • all of the above

With apologies to the owners in advance, I saw these vehicles at the recent Kit Car Show in Exeter.

Haynes Roadster Nose Cones

  • The car nearest the camera has a bonnet bulge and strong curvature to the nose cone with standard sized grill opening.
  • The red car in the middle has a high nose cone (approx 2″) with a shallow curvature and a large grill area.
  • The car furthest away has a shallow curve to the bonnet, a small bonnet bulge and slightly smaller grill opening.

Take note of the height of the bottom edge of the nosecone relative to the ground.

My personal preference; with no reflections on the cars or owners; is the first bonnet profile and bonnet bulge. I like the way the headlamps just peak above the front mudguards and nose-cone. I think I’ll go with the fibreglass bonnet, bonnet bulge and curved nose cone

Choosing the third option, there are implications. The side inlet on the Rover V8 plenum chamber will need cutting off welding up and moving to the front.

Rover V8 Plenum

Like they do on the Westfield Seight (Note the visible welding)

Westfield Seight Welded Plenum

And the much neater Seight2

Westfield Seight 2 Plenum Chamber

These plenum chambers have the air inlet and throttle flap at the rear, this is probably to clear the distributor etc, but I will draw it all up in CAD. Once this is done, I’ll make my decisions.

Hhhhmmm, Front or Rear?