[tractorpuller]

My cousin has a 2007 classic gmc. We just installed bully dog triple dog/outlook combo. On 130 horsepower setting he can hit 1800 degrees:help Everything else is stock, he is looking into 5" exhaust. Is there anything else we can do to get egts down. i dont know much about these motors so help me out please, i told him to take it easy so the aluminum dont start dripping. LOL! THANKS

 

[TurboBeagleBuggy]

You are moving in the right direction, need to get rid of the cat and block the EGR. There is a device called a Fingers Stick that will block the CEL and keep it setting EGR codes.

 

[Tow Master]

I agree. The cat brings the EGT's waaaaay up. Inside the cat there is a thick honey comb ceramic thats made to hold heat. Remove the cat and get a aftermarket muffler and your egt's will be way lower!

 

[TYREBOYZ_DEMAXIN]

also try the ppe boost controller,on my truck it drop the egt's by 200 to 300 degrees,an exhaust is a good idea.the 5" sounds the best.

 

[tractorpuller]

Well he ordered 5" exhaust and a blocker plate so we will see what that does. Where can we get this boost controller I have never seen it? do I asssume that it is similer to what we do on cummins, it just fools the computer and allows more boost? thanks

 

[TYREBOYZ_DEMAXIN]

i is perty much the same as that,here is the web site http://www.pacificp.com/index.php?main_page=product_info&cPath=2_14&products_id=15 ibought mine off of ebay i saved 100 bucks,with my stock charger i can push up to 36 psi

 

[TurboBeagleBuggy]

with my stock charger i can push up to 36 psi

Don't continue to push your stock charger that hard. Back the boost down to 30, your charger will thank you. The stocker has too high of drive pressures at those boost levels and causes your EGT's to run hotter.

 

[TYREBOYZ_DEMAXIN]

my average boost is 29 to 32 psi.i had it up 42 psi one time but it had a strange whine to it so i shut down

 

[TravelswithCharly]

Don't continue to push your stock charger that hard. Back the boost down to 30, your charger will thank you. The stocker has too high of drive pressures at those boost levels and causes your EGT's to run hotter.

I agree with beagleson. And NEVER put a boost enhancer on a 130 HP tune, which sports 24-26 psi. Or you will soon part ways with the turbo.

I have seen no value of having boost over 28 psi. There is a whole host of other problems that are created. IMO, NEVER use excess boost to reduce egt's. Let's think about it. We seek egt reduction to protect the turbo. Yet in dishing out another 5 psi, we are overspeeding it by 40,000 rpm, leading to a quick demise. Ironic...you see what I am saying.

Only 3 ways to easily reduce egt's. Advance timing, reduce overfueling, reduce exhaust restriction (a whole host of ways to do this, new exhaust, free flowing downpipe, LESS BOOST, etc)

 

[TYREBOYZ_DEMAXIN]

thanks for the warning and the info

 

[Diesel Nut]

I agree with beagleson. And NEVER put a boost enhancer on a 130 HP tune, which sports 24-26 psi. Or you will soon part ways with the turbo.

I have seen no value of having boost over 28 psi. There is a whole host of other problems that are created. IMO, NEVER use excess boost to reduce egt's. Let's think about it. We seek egt reduction to protect the turbo. Yet in dishing out another 5 psi, we are overspeeding it by 40,000 rpm, leading to a quick demise. Ironic...you see what I am saying.

Only 3 ways to easily reduce egt's. Advance timing, reduce overfueling, reduce exhaust restriction (a whole host of ways to do this, new exhaust, free flowing downpipe, LESS BOOST, etc)

Another thought to this as well is one that is a big deal with the Cummins trucks - compressor maps. Your turbo is designed to operate efficiently inside a certain window of boost numbers. Above that number, you produce a lot more heat in the air charge trying to compress more air than the turbo is designed to. This, in turn, leads to whats known as diminishing gains. The gain of the extra psi of boost is offset by the extra temperature of the charge.

Then, like posted above, you have the concern of over speeding. Remember these things spin somewhere around 150,000 rpms. How much faster you really want to spin it? Also, the extra speed and pressure makes life hell on thrust washers.

Good call on drive pressure. Lets talk about that for a quick second. The higher your drive pressure the better your chances of getting way to hot and of popping the head gasket. Drive pressure is the pressure between the pistons and the exhaust wheel. Most after market turbos have better flowing exhaust sections to get this pressure down. And, drive pressure is directly linked to boost pressure, so you really need to find that happy medium.

 

[TravelswithCharly]

More reading on this issue

DANGEROUS TURBO CONDITIONS

 

[tractorpuller]

well he got the blocker plate in last night. Took it out for a test and didnt see any drastic improvement. Still waiting on the exhaust, hopefully that does the trick. One thing is for sure I think this thing would spin the tires forever.

 

[TravelswithCharly]

Took it out for a test and didnt see any drastic improvement.

I would not expect to. EGR is off (no egr) when under load.

 

[TYREBOYZ_DEMAXIN]

One thing is for sure I think this thing would spin the tires forever.

i do love tire smoke.one night my brothers and i went out and laid down 2,000 feet of rubber:gearjamin ,the tires had 1/2 tread when we started and when we were done they were bald.ps it really helps to own tire shops when you do that,we get used tires in with some tread on then take them out and fry them off:tease :fart

 

[tractorpuller]

yea owning a tire shop does help. i dont really think he wants to roast these tires too quick. Brand new 265/75r16 nitto terragrapplers. Not exactly cheap. Personally till I sink some money in a tranny i cant spin mine long enough to lose rubber, way to much slippage. Dodge cant build an automatic. Back to my original egt question, what kind of egts do you guys see on these duramax? How much is to much, when do pistons and such start melting. I know all the diesels i ever been around 1250 sustained is around the limit. Sorry for the dumb questions just dont know much about duramax.

 

[TYREBOYZ_DEMAXIN]

i wouldn't think to much to run up to 1400 degrees for a very short period of time but for any lenth i try to stay under 1000 degrees.i don't know how much heat they'll take before they melt,i don't plan on finding out either

 

[LBZ Farm Truck]

mine will run a constent, 1100 and i have no probs. if i do ill let you know. Mines been HOT but no probs.

 

[serpa4]

Heard these LBZ turbos are only effecient to 34max. I'm running 30-31. I don't see why you can't add boost to the 130 setting. If you are keeping boost below 32-34, why not? Many programers don't add boost and thus run hotter and smoke more. Boost controller on my old Edge/Juice to raise boost was a win situation. Cooler EGT and less smoke. It did not add boost even on the 100+ hp setting.

 

[tractorpuller]

Serpa4 read the link in post 12 here, it explains all that boost stuff. More boost only helps as long as the turbo can safely and efficiently make that amount of boost. where are you guys putting your pyro probes? i put it in the passenger side manifold. Dont know if it makes a differance or not. I know post turbo is alot cooler.