im new to this supercharger thing and dont know what is a good reading. what is it supposed to be at when your idling and when your driving normally. it is an 04 with 40000 miles i glanced at it the when i first test drove it and it was in the middle i think. just want to make sure when i test drive it tommorow,

 

The boost gauge sucks. You can't tell much of anything by it.

It should be zero (below zero, actually) when you're not in the gas, and 8-10 when you are wide open throttle. But again, I would not use it as a diagnostic tool. If it does not read correctly, I would suspect the gauge before anything else.

 

What Tim said


But I will add. It has a built in boost bypass valve so your not always in boost and making heat when driving a steady speed in town.

I have never seen your basic Turbo set up Boost while at idle or when not under load no matter how much you rev. it. (some hybrid might??) but a super charger will make boost anytime. Thats why folks like them on drag cars. No lag.

You can see the guage rise if you goose it while parked or in neutral though. Thats normal.

If the 04 is stock with stock air cleaner and exhaust You ain't gonna see 10# on the stock gauge unless your intercooler is not working.

The intercooler in my 99 had the leak so I unplugged the pump and ran it a few weeks that winter while waiting for the replacement intercooler to come in.
That stock boost gauge would go clear up in the black then. Ounce I got the new intercooler I was 7ish at 6,000 ft. above sea level.

That 04 should be sweet with those low miles. Just do it

 

Good reading on the boost?

2 bar, 3 bar if you're a badass

 

3 bar - only if you want to send your Rods into orbit