Lb7 intercoolers and wastegate adjustment

[homerent@telus.net]

My 03 LB7 with a magnaflow 4", edge Attitude, and AFE stage 2 with a Banks Big head, pulls 25 psi of boost in 4th towing a steep hill at 2500 rpm. It tows great at 70 mph and gets 15+ us MPG towing. between 1500 rpm and 1800 rpm the torgue seems real weak pulling any kind of a grade. I emailed banks but got no response. Should I crank up the Big head to improve torque in that range.

My second question is I am starting to hear that aftermarket intercoolers make a big difference, in both power and mileage. can someone tell me thier experiences with the larger intercoolers. 1700 bucks is a large amount and I am hoping to find out how much difference it makes. Second question do they just benefit during towing or all the time given the cooler air going in.

Thanks

TG

[More Power]

The larger aftermarket intercoolers provide more of a benefit for competitive diesel owners who are running quite a bit more than stock boost pressures.

I'd like to see more dyno, track and road testing that compares the stock to aftermarket IC's. Not enough data out there to really know.

The '03 LB7 makes its best torque at 1800, according to GM. From an engine efficiency standpoint, 1800 up to 2700 or so would provide the best towing performance while pulling big trailers up steep grades. Let the powertrain programming pick the gear and RPM. It does a pretty good job. :)

Jim

[Mark Rinker]

1) Are you running stock diameter wheels and tires?

2) Do you always run in Tow/Haul when towing?

3) What Edge setting are you towing with? EGTs while on the grade, experiencing the sluggish performance?

[bigchev]

My 03 LB7 with a magnaflow 4", edge Attitude, and AFE stage 2 with a Banks Big head, pulls 25 psi of boost in 4th towing a steep hill at 2500 rpm. It tows great at 70 mph and gets 15+ us MPG towing. between 1500 rpm and 1800 rpm the torgue seems real weak pulling any kind of a grade. I emailed banks but got no response. Should I crank up the Big head to improve torque in that range.

My second question is I am starting to hear that aftermarket intercoolers make a big difference, in both power and mileage. can someone tell me thier experiences with the larger intercoolers. 1700 bucks is a large amount and I am hoping to find out how much difference it makes. Second question do they just benefit during towing or all the time given the cooler air going in.

Thanks

TG

I installed my new BD "Cool It" Intercooler yesterday. Did a long test drive today and noted that @ 70 mph on the Interstate that my egt's were down 50 to 75 degrees and that under full throttle accelleration 0 to 110+ mph the egt's were down by about 125 degrees with my Kennedy ECM on the 100HP setting. The install was pretty easy even for an old Guy!

[homerent@telus.net]

1) Are you running stock diameter wheels and tires?

Yes I am currently running stock rims and tires. When I change tires this fall I am considering upping to a 265-75R16 from the 245 stock tires which after 116000 km are down on the wear bars.

2) Do you always run in Tow/Haul when towing? YES

3) What Edge setting are you towing with? EGTs while on the grade, experiencing the sluggish performance?

Edge power level 2, currently pulling a 9000 lb trailer with a stock tranny. I sometime have tried 3 with better overall towing performance but EGT levels increase more quickly. I try to keep EGT's below 1300 by backing off the throttle. If it gets higher than about 1250-1300 degrees for any length of time I generally lock out the overdrive to get the rpm up which increases fuel consumption, but cools off the EGT