Banks Big Head adjustment

[homerent@telus.net]

I have an 03 Dmax LB7, 4" Magnaflow exhaust, AFE Stage 2 air filter, coupled with a Banks big head wastegate Actuator, and edge attitude. I just replaced the tranny at service with full synthetic.

The big head was just installed and I can pull 23 PSI towing. My question is would setting the big head up a little higher help low end torque or mileage. Normal highway speeds of 70 MPH pull about 3 psi of boost, where before the tranny service and big head the truck was pulling 5 PSI.

would there be any improvement in bottom end torque or mileage by setting up the big head a little higher. low end response and mid range towing was the reason for the big head. I do notice the turbo spools a lot faster at midrange but I have seen no response or slightly slower response off the line

Second, is the setting difficult to do or should I take the truck back to the perf shop where i had it installed.

Second, can anyone reccomend some cost effective tranny upgrades to increase tranny torque handling slightly.

thanks

[More Power]

You could visit the review we did for the Banks BigHead wastegate actuator to learn more about its operation and setup.

ATS Diesel sells a Co-Pilot controller and valve body kit that can increase the torque capacity of the Allison.

Jim

[Mark Rinker]

My opinion on your boost would be to leave it where you have it for daily driver and towing duty. Duramaxes are not immune to head gasket failure, and it seems that 25psi is about that threshold for extended duty.

Just my opinion.

[Kennedy]

I have an 03 Dmax LB7, 4" Magnaflow exhaust, AFE Stage 2 air filter, coupled with a Banks big head wastegate Actuator, and edge attitude. I just replaced the tranny at service with full synthetic.

The big head was just installed and I can pull 23 PSI towing. My question is would setting the big head up a little higher help low end torque or mileage. Normal highway speeds of 70 MPH pull about 3 psi of boost, where before the tranny service and big head the truck was pulling 5 PSI.

would there be any improvement in bottom end torque or mileage by setting up the big head a little higher. low end response and mid range towing was the reason for the big head. I do notice the turbo spools a lot faster at midrange but I have seen no response or slightly slower response off the line

Second, is the setting difficult to do or should I take the truck back to the perf shop where i had it installed.

Second, can anyone reccomend some cost effective tranny upgrades to increase tranny torque handling slightly.

thanks

The wastegate is shut tight and does not start to "leak" until you make both drive and boost pressures. This is why there is no off idle or light load cruise difference. Where you will see the gains is during mid and upper boost operation.

I put the Big Head on my 2002 quite some time ago. It works well, but is a pain to adjust. You need to apply shop air to it to release it and then if the linkage hasn't frozen you can adjust it in one turn increments. I now use my Boost Valve to tune the big head as it is a tool-less operation.

There are 2 key things that people forget/mess up when adjusting boost:

1) Always set to the highest power level that you intend to use. Higher power levels can increase boost further than you care to be.

2) If you stop gaining, stop adjusting. There just isn't any more to be gained, and again, if the power level is increased you could be off the charts...


As for economical trans upgrades, in my opinion there are none. The Allison requires clutches, increased psi TQ converter, etc and you can't get this done without removing the trans.

[Mark Rinker]

1) Always set to the highest power level that you intend to use. Higher power levels can increase boost further than you care to be.

2) If you stop gaining, stop adjusting. There just isn't any more to be gained, and again, if the power level is increased you could be off the charts...

If I can also make a suggestion, I tune boost with JKs boost valve, based on the highest power level at maximum load (towing weight) that you plan to experience.