Sorry, haven't checked archives or anything. New to this whole thing, the board as well as this is my first Real Truck and first deisel. I have a 2004 F350, Harley version, SD, Big Cab, Long Bed, fully loaded. It's awesome. I love my truck. Just had it lifted, put on really nice WELD Racing 20 in. wheels with 35 in. TOYO M/T tires. Also had the Edge Juice/Attitude installed with an AIRAID intake and a Bully Dog Exhaust. The exhaust comes out with a 4 in. pipe but then goes into a 5 in. before the muffler and the rest of the way. I'm not sure what boost is, why it's important, what damage can occur, etc. And it's of concern, because now with the Edge, I can see all this stuff. And, the Boost hits the 26 preset limit really easily. I'm wondering if it's related to amount of air because it seems the intake to the AIRAID is mostly blocked by a baffle around the grill. Guess the guys who installed it didn't notice this. I am planning on cutting the baffle away this weekend, but if that doesn't help, I'm a little worried. Thanks for any input you might have.

 

Boost is the compressed air flowing into the engine, atmospheric pressure is 14.7 psi at sea level, you are getting 26 psi. Too much pressure and engine damage can occur.

 

Mike- so what you are saying is that 26 psi is too much?? Ive read different on this board, and have read of other people running up to 32, including myself with the attitude...I dont have any links as I read it a while ago. I dont have the exact answer either really...can some one else chime in on this also??

 

Simply put, boost is the amount of pressure increase in the air pressure of the intake manifold over unboosted or nomally asperated operation.

Normally asperated engines use engine vacuum to draw air into the engine and therefore operate with pressure lower than ambient air outside the intake manifold (14.7 psi nominally at sea level).

The boost gauge measures the pressue over ambient, i.e., the gauge reads 0 even though when there's no boost present there's still 14.7 psi present. As the turbocharger gets spun up by the exhaust gasses, the compresser blades on the intake side of the turbo shaft grab the air coming in from the air filter and pressurize it and send it to the intake of the motor via the intercooler (this removes some of the heat created through the pressurization process).

Most '03 6.0 trucks make around 24 lb at max boost when stock - some do a bit more and some a bit less. I'm not sure what an '05 makes normally but if you are seeing 26 lbs that's probably pretty good.

Adding a tuner to dump more fuel into the motor causes more heat in the output which spins the turbo more which in turn creates more pressure on the intake side. It is not uncommon for some of the trucks with tuners to see sustained boost numbers of 32 to 34 lbs at max conditions.

 

That's about it

 

at 26 I would not worry to much. My truck is stock and I have seen it up to 30.

 

That's a huge relief guys! Thanks, and thanks for the explanation too.

flyMike - LOVE MY TRUCK!

 

Isn't this place GREAT...I learn something everyday

 

I saw 31lbs boost, everything stock, with the diesel tech sitting in the passenger side with his Ford WDS computer installed. I have an early 03. This was with the Dec 03 flash (3U7A-12A650-FTC) installed.