I bought a used inertia Switch (Rover) to add to my kit car.

It trips rather more easily than I expected!

If i hold it in one hand and shake it side to side it trips out. I can imagine when its bolted to a kit car with limited suspension it would trip out all the time.

Its difficult to quantify but Im just wondering if anyone has found the same but fitted it and found it to be OK.

It will be fine but it must be solidly mounted to a stiff part of the chassis.

IIRC mine was advertised as a Rover one (PBT-GF15), pic. might help identify it.
Actually works fine - in reality it takes a lot of inertia/retardation to activate it - ask my No2 son how I know!
HTH.
Cheers, Pewe10

I have a Rover switch in my car, hasn't ever tripped out when driving

What is the correct orientation for an inertia switch. I have a Ford one ( Fiesta/Puma I think ). Should it be mounted to a vertical or horizontal surface. It is not obvious from the fixing point. Any one know?

I have mounted mine at an angle, works ok if I hit it with rubber hammer!

My Ford Puma inertia switch is mounted vertically with the red button at the top. Never tripped during nearly 4 years of normal driving on Suffolk Roads or hooning around trackdays. I've been through one or more potholes in my time too and the switch never tripped, but I know my spine felt it!

Ed.

Thanks for all the advice.

Guess I'll just fit it and stop worrying!

Should be mounted vertical, with connector at bottom.