aftermarket auto meter phantom gauge pulls only 7# and factory gauge is buried.over and under pulleys which gauge is right and is this common.

 

So your aftermarket gauge reads 7#...

Your stock gauge is off the chart...

Not sure what you mean by 'over and under pulleys'...

How much boost are you running and when did you install you aftermarket gauges?

-dennis

 

sorry that whould be a metco upper and lowwer puley. just purchased L. in this set up .thankyou for the help .

 

if it has a upper maybee belt slip but u i cant see that causing that much boost loss.

 

is the gauge at "zero" when your truck isn't running? If not it needs to be calibrated....

 

yes after market gauge at 0 or vac just odd to me all help welcome

 

Sounds like you have a installation problem
Perhaps a kinked line or a leak somewhere

 

My thoughts exactly, has the performance suffered?
Bryan

 

dont know just purchased and trying to figure this thing out

 

I'm with Don on this one also.

For sure the factory gauge is inaccurate, not even usefull. It even shows vacume when it is actually in boost.

There is a pink high pressure line that the factory gauge connects to. The autometer should be T'd into that line. No cutting required. If you think that it's all hooked up correctly just get a vacume pump and connect it on the engine compartment side. The vacume pump should be able to hold the vacume assuming no leaks. The Autometer should be at least as accurate as the vacume pump.

 

does it have the boost bypass done to it, mine was hooked up wrong and I was loosing like 5-6 lbs.

 

boost bypass? where would i lok for this

 

Check here for a bad connection / kink


(thanks to Tim for the pic...)

Do you know how much boost you're supposed to be running?

I agree with the others, your aftermarket gauge is probably reading incorrectly...I would find where it tee's off from the stock one and trace the line. You might even want to check the connection in the back of the gague.

-dennis