I don't want to steer you away from your options, but maybe there is an option out there you are not familiar with.

I have mentioned it a couple of times, but you have the option to install a T4 kit from CSD or Irate and source a Borg Warner SXE turbo. The total cost is about $2300, but you can recoop some of the additional cost when you sell your OEM turbo, pedestal and up-pips if they are in decent shape.

There are a couple of threads going on now with the KC and T4 being the topic of discussion. There is more good information out there, but in older posts.

https://www.ford-trucks.com/forums/1...o-results.html

https://www.ford-trucks.com/forums/1...364-5-sxe.html

 

Not trying to but I think this would be a good place for this discussion and I would love to hear from others more knowledgeable than myself.

I want to learn more about turbo and diesel theory in general. One thing I really do not understand is the recommendation of a smaller / tighter exhaust housing on a manual truck. It is the general recommendation I see and the reason given is usually to help build boost quicker after a shift as you loose boost unlike an automatic. Ok that makes sense and I buy it.in general. If I was drag racing my truck I would agree and go with a tighter housing for that reason.

I'm talking Zf6 L 1 2 3 4 Ⓓ (overdrive) and the way I generally tow which will be different than you most likely.

When I am towing it I am usually accelerating smoothly shifting slow and later than "normal" to keep rpm where the power is. I am usually around 40 to 60 % throttle position when shifting thru the gears. Granted I do accelerate from a stop quickly at times towing to get up to speed before I hit a hill, trying to merge with traffic, or even accelerate up a hill and need to upshift during the climb. These are times when I see the smaller / tighter exhaust housing being a benefit as long as your drive ratios do not get out of hand.

Once I'm up to speed and in 4 or Ⓓ (trying overdrive symbol) depending on how fast I am going and what the road is like. Back country roads it may only be a few minutes or a half hour till I need to shift. On the interstate it may be 2 hours cruising along in a gear when I can get everyone's bladders synced up. This is when I hit a hill and the throttle goes to the floor to maintain speed or I want to accelerate to pass someone. Picture semi's slowing down in the right lane with the flashers on and me in the left with an ear to ear grin (while watching egt gauge) making the climb. It seems like to me I ask the most out of my truck when I'm up to speed and have already "picked my gear" so the need of a tighter / smaller exhaust housing seems odd to me.

Once again I am not saying I'm correct just what I think and would like to hear others thoughts and the reasons behind them. I had no regrets and think I made a decent improvement when I swapped to the 1.0 exhaust housing on my stock turbo after running it with a billet wheel.

 

Brandon, I agree with your confusion or lack of knowledge on the subject. I am in the same boat, at least it is not a sinking boat...

Like you, when towing at 55 MPH the truck is in 4th gear and very happy. When I get near 65 MPH, I shift to 5th gear (OD) and the truck is happy there. With my gearing it is right about 2 RPM for both of those speeds and gears.

I think this is where the smaller A/R is key. Most of the time the lower RPM for a turbo to get into its stride is below 2000 RPM. I know that some owners have tuned and set their trucks up to hit peak power and boost before that, but for most of our applications 2000 is a good medium area for boost and engine to be happy. Now, with my current setup once the RPM's are near 2750-3000 the boost is ~25 and as the RPM's climb, the boost will climb a bit more to ~28. Although, the boost pressure is not what we are chasing here, we are chasing freedom of air flow and lower pressures if possible coming out of the turbo. As I understand it, the more PSI from the turbo, the more heat.

That is a generalized statement, but in order to keep things on the simple side, I believe that is the only way to say it.

The article I have linked below is a good read and keeps things pretty simple for people like me.

Turbochargers - Boost & Drive Pressure - Diesel Power Magazine

 

 

I'm running a 38r with 1.0ar and auto trans. It doesn't like pulling at 16-1800 rpm it lights quickly but the boost pressure bounces almost like surge. Keep it above 2000 rpm and it pulls like a freight train. EGTs are never a problem with my stock sticks. It did get hot with the stock turbo though.

 

Wouldn't make a difference anyway because chances are their tunes are different, or their injectors are different or something is different. The only thing you can do is educate yourself as much as possible and make the right decision for you and your goals for the truck.

 

 

Markus, I was going to send you a PM, but I think you are still too new to the forum or something. So, I will post some of my thoughts here and do with them as you wish.

Choosing a turbo is a bit of a leap of faith for a lot of us. If you are anything like me, you try to be very smart with your money and time, because both of those are rare commodities. Money can be recouped a bit at times, but time is gone and will never come back.

I have been dead set on the KC38R, until recently when I have started to lean more toward the T4/BW 364.5 kit. This is only because Borg Warner is a big name in turbos. Their SXE line is fantastic. This is the line that the KC38R was designed after.

GTP38R ~$1200
KC38R ~$1500
T4/BW 364.5 ~$2300

Each of these has a bit of money that could be reclaimed by selling the parts you don't need any longer. Where the true commitment comes into play is where your goals for the truck are. If you are anything like me and want a reliable and efficient ZF6 tow pig, then read post #192 in the link below.

https://www.ford-trucks.com/forums/1...l#post17836637

To each their own when it comes to choosing a turbo.

Things I know...

- GTP38R is not for me simply due to noise levels and amount of performance gained over my modified GTP38
- KC38R is probably not for me because it is a hopped up GTP38R with billet wheels and slightly different housing that would most definitely produce more boost. Although, more boost is not what I am chasing. More air in and out of the engine in an efficient manner is what I am chasing.
- T4/BW 364.5 is probably where I am headed due to the shear performance, reliability and efficiency of the BW SXE turbo. The T4 kit, I am not crazy about, but in the end it is just tubing that is routed differently than the GTP38 is, that is all there is to it. These SXE turbos work at a 1:1 ratio, and if you read the link I posted above, you will know that is the goal for any turbo vehicle.

Again, this is your money and your time we are talking. But for me, I sure as heck do not want to spend $1500 and get a mediocre tow pig out of it where I still have to watch the EGT gauge just as much as I watch the road.