[no_worries]

Those guys at Pittsburgh Power specialize in Cummins motors. They'll probably want to put a bigger turbo on at a minimum but it might be worth talking to them.

[btinc]

As Special K said they are awesome, better fuel mileage and loaded to the max runs like you have a half a load on. I do have a after market turbo and exhaust, and i would not change my set up for anything. I love the box.

[allan5oh]

Probably what it is is that the turbo/exhaust setup does give you a little wee bit more power, but helps with engine efficiency and really helps the fuel mileage. The "box" wouldn't help with engine efficiency, and since you can "waste" more hp, it would kill your mileage. The two probably cancel each other out. If one got just the turbo and exhaust, mileage would definitely increase with no chance to waste extra HP.

[Teal 95 KW]

So, are you trying to say that the power gain is coming from the turbo/exhaust? A wee-bit of a gain? I know of a 475 Cat that with the box alone put down over 600 at the tires. That's a substantial gain, I see no "wasted power"..Now, if the exhaust and bigger turbo were added, then you are able to take advantage of the box, and run the higher settings.

[allan5oh]

I am saying without the box, just the turbo and exhaust, you will see some HP gain. The main "power gain" is from running the box, because it injects more fuel.

Generally, the more horsepower you have the more you will waste going 70 MPH+ up big hills, etc..

[Teal 95 KW]

Originally Posted by allan5oh

I am saying without the box, just the turbo and exhaust, you will see some HP gain. The main "power gain" is from running the box, because it injects more fuel.

Generally, the more horsepower you have the more you will waste going 70 MPH+ up big hills, etc..

Gotcha! Well, they state on their website that you will NOT see improvements on flat open terrain, climbing etc. I believe that they state that "typical" improvements are .2 tenths to 1/2 a mpg, and there have been guys who have gotten 1 full mpg but that's one of those "perfect world" scenarios.

[Teal 95 KW]

And, FWIW-As much as I would like to have more power, I have more than I need right now (can pull the Grapevine at 60mph grossed out) I don't understand spending $7k for the turbo, box, and exhaust when they even state the most drivers who have the set-up only run on the 2nd or 3rd setting of 7....that's an extra 75hp? No reason to spend all that money on the set-up when you have speed limits, and pushing the truck (at the 60mph I pull the grapevine at, my mpg on my dash display drops to about 3.8-ish) like that, you lose fuel mileage BIG TIME. I guess aside from bragging rights, it doesn't do a whole lot in the real world...other than get you in trouble.

[allan5oh]

Originally Posted by Teal 95 KW

Gotcha! Well, they state on their website that you will NOT see improvements on flat open terrain, climbing etc. I believe that they state that "typical" improvements are .2 tenths to 1/2 a mpg, and there have been guys who have gotten 1 full mpg but that's one of those "perfect world" scenarios.

If it doesn't make even one more horsepower, then the engine is running at the same efficiency as before.

[Truckdobe]

Have those of you that are stating that you "don't buy into this" actually tried it?? Or are you just stating your opinions??

I have not tried the Pittsburgh Power Box, but have dealt with Bruce over the years. I have taken a mechanical 425 to 600+ horsepower and GAINED almost a full mpg, as well as taking a truck from a pig to a pleasure to drive. I did NOT increase the rating of the transmission or clutch and ran it fine for years with no driveline failure (until it was stolen).

If I were planning to keep my current '07 I would definately buy the box, but since I'm not keeping it, I'm putting the $$ in the old 'B' model that I'll be driving in the future.

[allan5oh]

Originally Posted by Truckdobe

Have those of you that are stating that you "don't buy into this" actually tried it?? Or are you just stating your opinions??

Not opinion, but rather decent analysis. No I haven't tried it, probably wouldn't work with my Volvo engine.

It's not hard to understand, if you ram more air in the engine, it will become more efficient. Efficiency is BSFC (Brake Specific Fuel Consumption) which is the amount of fuel in lbs that is required to make one horsepower for an hour. Diesels are usually around .30, gas engines around .40. Lower is better, obviously.

Diesel fuel has a set amount of BTU's in it. You can convert directly from BTU's to horsepower, and doing this you'll discover most engines are around 30% efficient. The rest of the "lost heat" goes out either the rad or the exhaust. If your engine was 100% efficient, you wouldn't need a rad and the exhaust would be the same temperature as the air going into the turbo.

If you knew how efficient your engine was (bsfc), you could actually figure out how much average HP you need to travel down the highway.

Now given all of this, to increase fuel mileage you must create more horsepower-hours with the same amount of fuel. OR use LESS fuel and make the same horsepower with it.

Now this is where it gets tricky. "wasted" horsepower. This is HP that we're using in excess of what the truck actually needs. You travel faster, you're wasting more HP.

All I'm saying is with more HP, you have the potential to waste more HP. Up until the "original" HP of the engine(say a 475 HP cat turned up to 600), the engine behaves exactly the same as the old engine, efficiency and all.

Another thing I'm saying is that "turning up the engine" does not increase fuel mileage. All you're doing when you turn up the engine is inject more fuel, nothing more, nothing less.

If you allow the engine to breathe easier, remove restriction in the exhaust, reduce friction in the engine, increase compression, you both increase HP and increase efficiency. You CANNOT do one or the other. You aren't injecting more fuel, so if you made the same HP, you are exactly the same efficiency-wise.