my dad has an '03 GMC D-MAX with a stage 3 hypertech on it. he wants to get rid of some or all of the turbo lag, as much as is possible. what are the best ways to do this? one of his buddies who has a 7.3 PS says that it is laging because the wastegate isnt closing fast enough. this makes no sence to me, i thought the wastegate was only open under 'high' boost. is that right or no? any ideas on how to reduce turbo lag would be great, thanx.

you can try a Boost Valve from Kennedy Diesel ... I bought one and installed it ... it helps but if will never get rid of Turbo lag .... there is no such thing .... it is the way turbos work ... only smaller turbo spool up faster then larger ones ... but the value helps keep the waste gate valve closed and is slow to open it.... but once the pressure is gone it is gone.:(

this is a stupid question..but what is turbo lag??

my dad has an '03 GMC D-MAX with a stage 3 hypertech on it. he wants to get rid of some or all of the turbo lag, as much as is possible. what are the best ways to do this? one of his buddies who has a 7.3 PS says that it is laging because the wastegate isnt closing fast enough. this makes no sence to me, i thought the wastegate was only open under 'high' boost. is that right or no? any ideas on how to reduce turbo lag would be great, thanx.
Try a bigger programmer. I used Edge with Attitude. You can greatly improve lag by adjusting your low boost fuel adjustment on the Attitude monitor

this is a stupid question..but what is turbo lag??

Turbo lag is when the exhaust does not have enough pressure to sping the turbo enough to create the boost needed. It happens when you are at idle or low rpms. It takes a second or 2 after you press on the pedal for the engine to produce enough exhaust flow to spin the turbo up to create the boost that the engine needs to create more power.

banks big head waste gate actuator, in combo with the PPE boost increase valve. significantly lowered lag for me, but as previously stated, you will never eliminate lag completely. But it never hurts to try!

You are correct that the wastegate is normally closed and opens only at high boost levels. By the time the wastegate opens any turbo lag is already history because it probably will never open without the turbo already being spun up.

my dad has an '03 GMC D-MAX with a stage 3 hypertech on it. he wants to get rid of some or all of the turbo lag, as much as is possible. what are the best ways to do this? one of his buddies who has a 7.3 PS says that it is laging because the wastegate isnt closing fast enough. this makes no sence to me, i thought the wastegate was only open under 'high' boost. is that right or no? any ideas on how to reduce turbo lag would be great, thanx.

I always thought the Hypertech stage 3 ran pretty good on my '02, but the only way to reduce turbo lag on the LB7 is to change the programmer/tuner...Fuel and timing will change the characteristics of that engine...A boost increase valve will only chage the PSI when the wastegate begins to open...I've also learned after spending $180 on a Banks Big Head that the factory wastegate is sufficient to do what we want it to...Better off getting an adjustable boost increase valve from www.kennedydiesel.com than buying the Big Head, it's easier to adjust...

an exhaust and edge ez helped me get rid of a lot of the turbo lag before it was dangerous to pull into traffic

Tuning will fix it.

T:cool: NY

so a KD boost valve and exhuast are about the best ways to reduce turbo lag then right? the truck does run great...once the turbo spools. from low RPMs almost feels like it is out of gas, just no go. once it spools though, holy s**t, here we go! thanx for the input guys, any other info/ sugestions would be great.

Exhaust, minus the cat, and air intake will help and the boost valve will let it make more boost, but like Moonshine said, the majority is in the tuning...