Rollin' Smoke

I just put a adjustable boost elbow on my 03 HO......Well it is peaking out at about 28psi, but I have noticed that it will pull hard off the line but then falls on its face. After a couple seconds the boost comes down just a bit and then the truck takes back off. Since the truck is basically bone stock i think that I have a problem with the truck defueling or its running out of fuel. I really dont think its running out of fuel because I have no power adders. what you experts think about this?

qmcdt

The truck is defueling. Now you need a boost fooler. ECM see's over 20-21 it defuels. If it lasts long enough, it'll throw a code. How are you see ing the boost anyway? Did you install a gage? Put in a boost fooler and it'll stay up there. 36 psi on mine with the edge in level 3 with the foot 75% home and the speedo crossing the 60-65 mph mark like nothin.

Rollin' Smoke

yea I have the ISSPRO gauge so I can monitor the truck.....I plan on adding a programmer real soon so I went ahead and got the gauges. well before the new elbow it was pulling about 24 psi without any defueling. at what psi is the pcm going to defuel the engine?

qmcdt

It's difficult to describe, as there are soo many things that control your fueling rate. Not enough boost cuts your fuel (no black smoke please), as does too much boost (NOX), reaching speed/rpm, high coolant temp (aka limp home) and many more I'm sure. The ecm has a program and it follows it blindly. That's why some dude built a boost fooler. "No baby, yer only getting 21 - 22 pounds boost, honest you can go with full fueling, we aren't quite up to speed yet" when it's actually getting 35 psi at full fueling rate making NOX like a pig. The unit from predator lies about both boost pressure and fuel rail pressure, raising both to make more power then you can now, or with a boost fooler. The way I understand it, if you simply put a resister inline on the boost sensor, you'd get more power on the upper end because it can't see the true boost pressure so it would fuel at higher rates on the top end. However, the bottom end would suffer as it wouldn't see the boost available down there. These foolers let the lower signal through, and reduce the upper signal to keep the fueling up. In essence, it re-ranges the output of the sensor so 0-40 psi looks the same as 0-22 psi.

XLR8R

You're gonna love aftermarket fueling!

Rollin' Smoke

well about a week ago I put my buddies BullyDog TripleDog on the truck and it was great.....truck ran like a champ, even the wife was impressed. actually the truck ran much smoother throught the entire RPM range.