Adjusting ride height

[wuckfitracing]

My car is up on my ramp and whilst Its there im going to raise the ride height as when touring some of Scotlands roads last year it decided it wanted to file down the rear anti roll bar on the tarmac every now and then. Ive measured the rear and its 135mm from floor to the chassis outrigger corner plates. The front is also same !
Can anyone confirm it should be 150mm at rear and 140mm at front, give or take 5mm. Im off to Spa classic in May and dont fancy grounding on the ferry ramp ( The missus MX5 did last year).

[wuckfitracing]

Sorry should have mentioned. About 2 years old Gas Gold Pros. Less than 2000 miles on them. They work very well and have 400lb springs on the rear (if I remember correctly). Full geo set up by a company in Sheffield. Just too low. Hence my question does anyone know what is normal. Oh and standard size wheels and tyres 15" on front and 16" on rear.

[wuckfitracing]

Thanks chaps, as I thought 135mm front and rear is too low.