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I've been doing some towing and I think my boost is topping out too low. I had it to the floor on a 8% grade and only hit 16.1 psi. I have no obvious leaks. My first thoughts are up pipes. Anything else I should be looking at?
Need more info, What goodies are under the hood? any turbo mods, tuners, intakes or exhaust, my stock 99 7.3 topped out at 15 psi, now I have it worked and pushing 30.
It disables the wastegate and allows the stock turbo to build more boost. You can put it back to the original state at any time you wish - some stick a small bolt into the black boot at the end of the red tube or push it on one of the boot clamps.
No mods. Everything is stock. We'll as stock as a 14 year old truck can be
16 psi sounds about right then for a completely stock setup. I could get 17 psi when i was stock. I changed to the ww2 and in my stock tune i can get 22psi now. 30+ in other tunes...
Cap off the red tube that goes to the wastegate controller on the turbo.
What are the "side effects" of this mod?
I've never heard of any on a stock truck - even when chipped. The stock turbo is rated up to 30 PSI, but a stock tune will limit the boost to 22 PSI. A chip can coax up to 30 PSI out of the stock injectors, but that's with air mods as well. With the red tube on the wastegate, you get 16 to 17 PSI boost, and that's all you'll get.
I've never heard of any on a stock truck - even when chipped. The stock turbo is rated up to 30 PSI, but a stock tune will limit the boost to 22 PSI. A chip can coax up to 30 PSI out of the stock injectors, but that's with air mods as well. With the red tube on the wastegate, you get 16 to 17 PSI boost, and that's all you'll get.
I've never heard of any on a stock truck - even when chipped. The stock turbo is rated up to 30 PSI, but a stock tune will limit the boost to 22 PSI. A chip can coax up to 30 PSI out of the stock injectors, but that's with air mods as well. With the red tube on the wastegate, you get 16 to 17 PSI boost, and that's all you'll get.
Interesting...I need to see if mine is capped or not because I have seen 20 or so PSI on mine, and other than a Bully Dog 6-shooter it is stock. Did these trucks have Cat Converters stock? If so mine is gone, would that be considered and "air mod"?
I've heard of the "7-turn" mod on the wastegate, there are adders that bleed the wastegate control signal (I found one on my truck after I started to learn what does what), there are variations of boost foolers (I discovered a cheesy one on my truck), but this does nothing for the wastegate.
There are few trucks that came with cats, so it's not unusual for it to be "missing".
Air mods:
Turbo - (different wheel, different turbo, ported housing, etc....)
Wastegate - as discussed, adjust the control rod or cap the red line - and some delete the wastegate.
Bigger exhaust - many go with the 4" turbo-back approach (stock is 3.5"). I have seen and heard stock, 4", 5", muffler delete, mixes of stock and aftermarket, stacks, tailpipe out the bottom, etc.... I tried the muffler delete myself and it did nothing but make the truck obnoxious for the neighbors - no performance change. I did the 4" and I logged some data that showed me the turbo performs better above 20 PSI with some other mods and stock injectors. In my view, any mod to take the engine HP above stock benefits from a 4" exhaust or the like.
Bigger intake - this one is huge. The stock intake has so many flaws that it takes 20 minutes to read the "scientific evaluation" posted by Y2KW57 on another thread. Many people opt for the 6637 and like the results. I had the Ford AIS (manufactured by Donaldson, and is the format for all Superduties from the 6.0L and newer), but I outgrew it when I went to bigger injectors. I sold my used AIS to a member here and he swapped out the 6637 that he had. He posted a very favorable review of the Ford AIS, and I really miss the quietness of the AIS... but I needed more air. There has always been a grand debate on whether a Cold Air Intake is better or if it even makes a real difference. The encyclopedia guys won't touch this one, because of the popcorn factor. I'll just say all factory intakes on the Powerstrokes are Cold Air Intakes - no dispute there.
There are other mods to make the boost system more robust, once you get past the 22 PSI defueling limit of a stock tune. Basically - if Riffraff Diesel sells a boost mod, I shoved it up Stinky's nose.
