Hey guys, I had the stage 1 installed last week and it was peaking a nice 26psi then creeping to 24psi and now it starts at 15 and creeps to 20psi.

Heck, if i floor it at around 50mph it will only build about 15psi

Is it the different air or what? I have no other mods and my car is a automatic HHR SS.

Thanks!

 

There is no one set boost and it will vary due to loads, speed, gear, Torque managment, temp, alt, etc.

There are times you will see max boost and other times only 15-17 psi at speed.

The computer will adjust to give the performance needed at speed and it is not always the same depending on conditions as demad.

What you are seeing is what we all see and you are not always going to see the max boost everytime you floor it. The computer just does not work that way.

 

Keep an eye on the boost. As Hyper says it can vary, but if you find you can't ever get it to boost to 20PSI anymore, something is likely wrong.

 

Today it's running fine, boosting 25-26psi then going down to 24 lol i guess it had a off day

 

Don't rely on the boost gage to monitor power..use your self senses to do that...there are way too many variables that regulate everything on that motor so the gage is not an actual indicator of performance....old school setups would spool up the turbo until you liftd or something broke,,,not this baby,,GM doesn;t want to have to use its powertrain warrenty......................

 

I don't understand how you guys are getting 25-26psi, I have never seen more than 20-21psi. Most of the time it will only go to 18psi.

 

Depends on the altitude that you're living at. Anyone w/ an SS in Denver CO for example will NEVER get the boost as high as someone living at sea level due to there being less oxygen in the air in higher elevations. Temperature and other natural factors play a part as well. Thanks, now you made me use my head on a Sat. morning and it hurts now...

Later
Allex

 

I posted this on a thread some time ago, but I thought that it applied here. If you understand the potential energy content of air in a given state, you will understand its effects on pressure, both compressed (boost pressure) and general atmospheric:

Before I brought my HHR SS in for the upgrade, I was seeing about 13-16psi of boost in the seasons of the year when air enthalpy in my region is at its highest. After the upgrade, I saw 19-22psi. This has fluxuated some, but I still get these numbers when energy content in the air is optimal per seasonal conditions. I have done nothing with the tubing (intake or exhaust).

If you keep the intersecting lines of a psychometric chart in the back of your mind when you're nailing the throttle and looking at the boost gauge, you'll be more apt to understand the discreet nature of boost pressures. (you don't have to memorize the chart, just understand it).

Hope this helps ease some anxiety...

 

Let me translate. It is not going to be the same all the time.

 

hyperv6, great translation! I have the problem that many engineers have with scratching my right ear with my left hand.

I just like to back up my claims with fact. Amazing how many don't understand that the properties of air is not as simple as it appears. Being in the business, I'm sure that you could appreciate that.

The explanation was meant for those who might want go go further down and under.

Bottom line is that a " wet finger to the wind" in the morning will tell you how much boost you should expect to see on the meter.