Is my tach right?

[71GMCer]

I finally have been driving around and im just questioning my tach,

Its a 350 sbc with a 4bolt main

It idles without choke at around 8-900rpm and with choke around 1000-1500rpm...my shift point is around 3000rpm because thats when it starts getting loud and obnoxious (open piped with glasspacks)


Correct? If not how do i fix it?

Also, It seems to no work after been sitting in the sun so ive been tryin to park in the shade...but once it cools down it works fine...is this normal? The back is black so it gets really hot.

Matt