MY 05 LLY IS SCARY FAST FROM A ROLL AND ESPECIALLY ON THE E-WAY, BUT MY FART IS FASTER OUT OF THE HOLE......... IS THIS BECAUSE OF TURBO LAG OR WHAT? IM RUNNIN EDGE/ATTITUDE, MBRP 4" CAT BACK, AND AFE INTAKE. I JUST THOUGHT IT WOULD BE SCARY SENSITIVE, WHEN IT CAME TO TAKE OFFS AND IT NOT. ANY SUGGESTIONS? OH, WAND WOULD MY EXHAUST BE BETTER WITH OUT THE CAT?:grd:

definately the turbo lag. removing the cat will free up some exhaust pressure and get it to the turbo. you;ll notice quicker spool rates, and a higher pitch and audible turbo whistle.

Does the truck throw codes when the cat is removed? I'm doing a 4" exhaust soon and was considering cancelling the cat with the LB7 pipe but I don't want to deal with any BS. Should I be concerned?

To limit smoke on hard acceleration, the engine computer holds back fuel until the turbo spools up. Edge has a setting to allow more fuel at lower turbo speeds. Crank it up to #5 and the lag will be minimized. However, fuel mileage will go down and you will be puffing black when you punch it.

4" exhaust can set codes. Search this site for "finger sticks" it is an accessory to fool the computer when you have big exhaust or no cat. Cost is very reasonable.

You're also getting about 6500 lbs of mass in motion, a little bit of physics here. These things aren't Porches. Surprising, however, what the DMAX will do once they get a little way on.

The Juice/Attitude is definately lacking out of the hole. You can switch out your CAT and get an aftermarket intake and the lag will still be there. The best tuners for bottom end are the Predator or PPE Xcelerator which are very responsive.

I understand its a big truck and it takes a bit to move it but shouldnt it launch even from a roll. when I put my foot on the gas it bogs then takes off, what the hell is that? fuel filter maybe or no?:cool:

I understand its a big truck and it takes a bit to move it but shouldnt it launch even from a roll. when I put my foot on the gas it bogs then takes off, what the hell is that? fuel filter maybe or no?:cool:THe answer is already here, its the TURBO LAG, drive any car with a turbo and you will experience the lag, take that cat off it will improve spool up but you will still have that little stumble.

Nitrous will help alot.:D

Seriously, it's a fairly big turbo with a large intercooler. It will take a couple of seconds to get serious response from it. A smaller charger and cooler would have given more response.

These engines are designed for towing heavy loads. Instant throttle response was given up for good torque under sustained load.

You can also get the turbo wound up a little by power braking while throttling up prior to releasing the brakes to go. Remember, all of this cost $$$ in fuel and wear and tear on the components.