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Discussion Starter #361 (Edited)
Looking to the front yard, a bird in the hand is worth, wait, a bird in the bush is worth... no, the darn thing just flatly missed the birdbath. Wow, the water sure feels funny today!

Bird in the Hand.jpg
Bird in the Bush.jpg
 

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Discussion Starter #362 (Edited)
Drilled and installed the pyrometer. The probe does not touch anything. The picture of the probe does not do justice. There is a bend in the manifold where the end of the probe is. The end of the probe is close to the wall but doesn't touch it.

See pics. Pyro Location.jpg Pyro Probe.jpg
 

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Be careful on the porting. You could actually lose power. I did a lot of research years ago plus I've lived beside a shop that built high performance engines. The trick on the diesel is not to over think it. First thing to port is the exhaust manifold. Lay the gasket on it and open up the ports to match. Now for the head. You do not, repeat do not want the head ports to be the same size. Mark inside the gasket with a broad felt tip pin and clean up the port leaving the mark. You want the exhaust gases to go from a smaller port into a larger one. That increases gas velocity which will help some on turbo spooling. You do not want to do much work inside the valve chambers as that can screw up gas flow if you grind in the wrong places. Gas engine head porting is totally different than diesel. You aren't turning 7000 RPM or more like a racing engine.
 

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Discussion Starter #364
The ports on the head are already smaller than the exhaust manifold ports. would it be advisable to just leave it alone? The exhaust gases are already going into a larger chamber once it hits the exhaust manifold.

Thanks.
 

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You can enlarge them some and clean them up a bit. I'd do the exhaust manifold because that is simple and won't hurt anything. Don't do any grinding on the turbo side of the manifold. You'd want at least a 1/16"- 1/8" smaller perimeter inside the head ports just to be safe if you do them. Sort of set a limit and try to make them all the same. When dealing with a turbo diesel, port work hasn't been a high priority item. Gains are probably small unless you plan on porting the intake side and that is a major operation. One item that can have good benefits is ceramic coating of the exhaust manifold and turbine housing. We don't have a lot of guys doing that either mainly due to cost. Keeping the heat inside those parts gains power since that is the driving force for the turbo. Not sure about current prices but years ago I checked with one company and it was near $1000 for the 2 parts in a high quality coating which had a rating of 2500 deg F. One company in California may be many times that. Their coating has a heat rejection of around 6000 deg F. Jay Leno has used them, but he can afford it.
 

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The ports on the head are already smaller than the exhaust manifold ports. would it be advisable to just leave it alone? The exhaust gases are already going into a larger chamber once it hits the exhaust manifold.

Thanks.
In my opinion, I say leave it alone. At <250 HP, I don't think you'll see significant gains. Considering, this is your first Cummins engine and it sounds like you haven't done porting before, you won't have anything to compare before/after. If you decide you want more power later, the cylinder head is easy to pull and re-install. I'm speaking from my experience with 12 valves as I have never owned a 4BT. If you pull the head for porting (and additional power), you can reinstall it with ARP studs.
 

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Discussion Starter #367
Thank you both for the input. I am not looking for power per se, but efficiency. I am happy with the upgraded turbo (HX 30 Holset), 3200 gov spring, and the upgraded injectors. If true, the gain is minimal then I will stay with what I have. One less thing to screw up so to speak. This truck will be a daily driver. The heaviest load will be a 4x8 trailer I use to haul my kayaks to the waterways. Even at 150 - 200 hp, I will not race or stress the engine, I am too old for that. I am back to the intercooler issue. Any suggestions of where to purchase the tubing necessary to plumb the intercooler?
 

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I used the SS bends from these guys.................
I was able to do everything in hard lines except for the straight boots,this resulted in no more blown boots on the hot side in the summer a problem I had been battling
100_3186.JPG
even when I was running the he221 with a fairly modest boost of 28 psi. Vibrant makes boots that use either Nomex or kevlar reinforcement Vs polyester and they work much better on the hot side when both temps and boost are high.
 

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Discussion Starter #369
Do those pipes come pre-bent? Or did you fabricate them? Looks clean, and impressive. Where is your air filter? I only see a tube running to the bottom of the vehicle.
 

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Thank you,
They come in standard angles 15* increments i think, it was necessary for me to start with them and then cut and weld various pieces to get what I needed.
I did the cutting/fitting then secured them with masking tape and had them TIG welded as my welding skills were not up to the task.
My air box connects to the blue 4" 90* and fills the open space above the 4 holes on the inner fender.
100_3212.JPG
 

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Discussion Starter #371
Looking at prices this won't be cheap either. A five-foot section of straight pipe is $111.00. Vibrant does have some cool stuff though. I was surprised their bead runner was $379.00 and the same product bearing the "Vibrant" name at Summit was $319.00.
 

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Looking at prices this won't be cheap either. A five-foot section of straight pipe is $111.00. Vibrant does have some cool stuff though. I was surprised their bead runner was $379.00 and the same product bearing the "Vibrant" name at Summit was $319.00.
The mandrel bends from silicone intakes tend to run ~$20.00 each and have beads formed on both ends that was the route i took and it was fairly inexpensive in the long run......$.02
 

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Ah shuck, Steve. I thought you'd invented the first invisible air cleaner. LOL. The one nice thing about the old Ford trucks is they have big, roomy engine bays and looks like you've used most of it.

T Swindler, improving engine efficiency is a good thing but often comes in small doses. Sometimes involves a bit of trial and error. Adjusting injection pump timing, fuel, turbo boost level, and many other little bits can help. A larger air cleaner and cold air feed can help. The ceramic coating I mentioned or even a turbo blanket can help. Even a different cam grind can help but that starts to get into the expensive tweaks. Another that isn't all that expensive but needs to be done during a rebuild is having pistons and bearings coated with hi tech materials. A company named PolyDyn is know for that kind of work. Might even change injector nozzles and get a little improvement. Cummins engineered the engine pretty well so giant improvements are hard to find.
 

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Ah shuck, Steve. I thought you'd invented the first invisible air cleaner. LOL. The one nice thing about the old Ford trucks is they have big, roomy engine bays and looks like you've used most of it.
Charles I have used it all and more, those inner fenders are "one offs" and sit ~6" lower that the factory ones.
 

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Discussion Starter #375
So far I have done things slowly and with consideration to cost. I am still perplexed on how to fit the intercooler. Looks like it will take some fab skills which are almost out of stock in my backyard. :unsure:
 

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Discussion Starter #377
They have a lot of stuff there (Intake Hoses | Intakehoses.com - Couplers, Elbows...) The prices look better than other places I visited. The second site looks good too, especially for silicone items. Thanks!!!
 
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