Manifold Pressure Alert

[Charley67]

My Edge CS2 has a manifold pressure alert which goes off every time I go full throttle. I've read several articles, most not the "for dummies" versions. Would I damage my truck if I raised the alert level from its present 39? My boost guage is reading low 20s when I get the alert notification.

 

[Mikey-KE7LBB]

I would remove the alert entirely and pay attention to boost instead.

 

[lpennock]

alarm is to low. it is going off at 25psi boost. you need to set the alert for at least 45 psi.

 

[Charley67]

alarm is to low. it is going off at 25psi boost. you need to set the alert for at least 45 psi.

My alert was set at 40, but was going off at 25psi on my boost gauge. I turned the alert off, and I have the alarm on my boost set at 40. Hope this is a safe setting.

 

[lpennock]

My alert was set at 40, but was going off at 25psi on my boost gauge. I turned the alert off, and I have the alarm on my boost set at 40. Hope this is a safe setting.

FYI. 40 psi of boost will be about 54-55psi on MAP. They are offset from each other by 14.7 psi at sea level.

 

[Charley67]

FYI. 40 psi of boost will be about 54-55psi on MAP. They are offset from each other by 14.7 psi at sea level.

Is there a practical reason for this? Do I risk any damage to my truck with boost alarm set at 40?

 

[lpennock]

Is there a practical reason for this? Do I risk any damage to my truck with boost alarm set at 40?

Manifold pressure is actually Manifold Absolute Pressure. At sea level that is 14.7psi. Zero psi would be outer space. Boost pressure is the amount of pressure over ambient pressure hence the difference.
A lot of people run peak boost numbers of 40 psi. It shouldn't be an issue at Sea level; however, at 10-12k feet you're probably over speeding the turbo so I wouldn't want to to stay at that boost for any length of time.

 

[Charley67]

Manifold pressure is actually Manifold Absolute Pressure. At sea level that is 14.7psi. Zero psi would be outer space. Boost pressure is the amount of pressure over ambient pressure hence the difference.
A lot of people run peak boost numbers of 40 psi. It shouldn't be an issue at Sea level; however, at 10-12k feet you're probably over speeding the turbo so I wouldn't want to to stay at that boost for any length of time.[/QUOT

Thanks, that's a very understandable answer. I am doubtful that I will actually make 40psi boost, but I have my alarm set there. Thanks to everybody for the help. I'm learning a lot from this board.