Gapping - what about that big heavy lump in the back?

As the metalwork drew toward a close, and thoughts turned to paint, gapping became a bit of a pre-occupation. More on that later, but I wanted to share the results of a little experiment.

One Porsche painter said to me that they prefer to re-gap with the engine and gearbox in the car. In their view, on some cars, the door gaps move quite a lot when that lump of mass is added, and they like to compensate. That got us thinking. Barry hadn't heard of any painter doing that sort of pre-loading on one of his shells but, as you might imagine from someone whose email address is doorgap@, he wasn't inclined to let it lie.

So we did a little experiment. First: find the required mass we could hang off the rear engine mounts to simulate the engine and gearbox in their correct places. A few calculations and...

... we concluded that hanging 80Kg off the rear engine mounts, with the front engine / gearbox mounts attached to the jig, would be a close enough simulation.

So after the first proper round of gapping, with everything looking quite nice, we tried it out.