I've been seeing all these trucks with drive pressure gauges...what is it and should I be monitoring it???

Drive pressure is reading what the back pressure of the exhaust is up to the turbo. High-hp guys use drive pressure and boost gauges to get an idea of just how efficient the turbo is working and if their combination is correct.
Here is a thread that has some good info on it: http://www.dieselplace.com/forum/showthread.php?t=251161&highlight=ideal+drive+pressure

Stock trucks do not need a drive pressure gauge.

my trucks not exactly stock...i just keep about reading guys with pullin trucks having drive pressure gauges and was wondering what it was all about...thx for the info...

Yeah...they monitor drive and compare to boost output per given rpm.

So what all have you done to your truck?

Moved to Other Performance Discussion...

i built an intake for it edge juice with efi live wrote with it 4" exhaust to a 5" single black stack suncoast 5 tranny eaton locker front and rear...custom turbo built by area diesel...45psi of boost...arp headstuds...traction bars...air dog 150...couple ltl secrets ive done to it

and twin cp3's

Sweet setup. Based on that, you would probably benefit from running a DP gauge.

yea it dynoed out at 617rwhp and 1119rwtq it runs like a champ...ran 7.6 in the 1/8 mile at 94 mph so its in the low to mid 12's in the 1/4

Stock trucks do not need a drive pressure gauge.


Why?

Why?
I THINK HE WAS REFERRING TO STOCK TUNED TRUCKS

Why?

Yes, I meant a stock truck. The o/p originally posted this is LB7 and didnt state he had a modded truck in his first post, so my reply was based on that.

I guess I could ask the same thing, though...why/how would a stocker benefit from one? I know in my/Rick/Chris's cases it would probably be a good idea because we're pushing so close to the edge of the turbo map, but I cant see any need for it on a stock truck.

The original post don't say this is an LB7 or that it is a stock truck. It is pretty obvious that a stock truck don't need any gauges. Assuming the only style of Dmax was the 3.5 year run of an LB7, I might agree. Since the VVT has been introduced on the Dmax and has been the factory style charger for 5.5 years now, I can't say monitoring drive psi is not needed. The failure of any electronic device or mechanical device turbo related on a Dmax with a VVT can cause a great deal of damage to the engine even in stock form. Although the truck might set a code or enter limp mode, the problem can normaly be identified a lot sooner by watching a drive psi gauge. Drive psi is an important paramater to monitor on anything that is turbo charged, and our trucks are no exception.

Bob, he posted it IN LB7-engine originally. I hit "s" instead of "n". Sorry.

so if I'm running one of your tunes in the library BOBO? it doesn't heat it hits 1100 wide open. If I had too much back pressure wouldn't I see it in the egt's?

P.S BOBO did I see you live in Washington? where abouts?

I just put a set of boost/drive press gauges in my truck last week. These VVT turbo's sure do some weird stuff with drive pressures. I was suprised that when you stand on it, until the boost comes up, i will see around 40 PSI drive with under 10PSI boost. After the charger spools and the motor winds up they will almost match, which is good for power. Just don't try to watch the drive press gauges as you bang through the gears. I wish i had efi live to see if i could tune out some of the crazyness of the charger.

I always heard a 1:1 ratio was pretty ideal for a turbo. depends on how much fuel or how cranked up the engine is I suppose. cause I'm sure there is a point that the backpressure is excessive and the turbo is out of its efficiency range right? so where do I get a back pressure gauge? or is this a home made setup?

if you intend to increase power adding various gauges now would allow you to monitor the gauges and start to put together how the truck is responding to changes as they are made thru various mods. it could help with learning curve when you have more going on.

Yeah I just happen to have a new boost gauge but IIRC its only a 35psi one so thats probly not gonna be enough but they are cheap and I agree it could help for sure.

mine is homemade. I have a manual transfercase truck and where my
4x4 buttons should be, i put in a pair of 1 1/2 gauges. You can get them from McMaster Carr if you don't mind the industrial look!