I'm not sure what it should be reading (please excuse my ignorance).
At idle it reads -0.6
and the most it reads is about 0.9.
Its a HKS gauge and the scale is marked as "x100 kPa", is that the same as bar?
also the needle doesn't sit quite on zero, is that normal?

Thanks
Steve

 

1 bar = 100 kpa

So your 0.9 x 100 kpa = 0.9 bar

 

and both are normal and aceptable readings

don`t worry.

 

Steve
Glad to see you're succumbing and adding more and more to your car Downpipe yet?