Truckjerk

Reading these posts about "boxes" "modules" what ever you choose to call it...has confused me a li'l' bit.

How are the torque and horsepower "adjustments" made independantly when horsepower is a calculated figure derived from a measured torque figure? I just dont understand how its possible unless they are calling "horsepower" something different than its actual calculation.

"horsepower" is at (ie)"5" while torque is at "1" how are they not proportional without massive rpm variences. Do the dynomometer "curves" not intersect at 5252rpm in some states?

Maybe Im as ignorant as the villiage idiot....

tcr

I think!!! not sure though, w/ the type of box your talking about you can adjust timing/fuel psi/duration, I just may be the village idiot.

Truckjerk

Well then what is the ideal setting.......cant use horsepower without torque getting you moving...need traction to start. is there a traction 9 setting?

chuckr72

i think what you are referring to is the tst box, which has 9 horsepower levels, and 9 torque levels, so you can adjust the levels to add more horsepower and keep the torque the same or you can add torque as well, and so on. hope this helps

Truckjerk

I follow that part, but dont follow how you can adjust one without adjusting the other if they are directly proportional. Simple changes like timing, fuel pressure/ delivery etc within the same RPM range and be able to control your outputs?. I could understand some horsepower "free'd up" due to being less efficient and the like etc...but to be able to increase measured torque and not have horsepower gained or vice versa just doesnt make sense to me.

Barrett_Fodder

I think (and correct me if im wrong) that i understand your problem. You are correct you cannot change one without affecting change on the other. However think of it like an equation. If i want to change one side, say in this case torque. Then in order for the equation to hold true the other side will somehow change like the divide by 5252 thing for calculating the first derivative of torque...which is horsepower. Now if the box is allowing you to keep a relatively stock hp setting then it must be affecting change in the RPM where the hp peaks...

(TQ X RPM)5252 = HP

So on a setting of say 3/1 for example you would see a slight hp increase but since the torque increase is higher proportionaly than the hp increase is the rpm at which the tq peak is reached must then be dropped further down in range. Try running a few examples using the 305/555 dyno curves then change one side of the equation and watch the subsequent change in the other.

I hope this helps illustrate what is occuring... How it is occuring is another lecture for another day...

LinearX

I think the simple answer is this. When you are changing the first setting, you are increasing the amount of power that the TST is adding to the engine. When you are adjusting the second number, you are controlling how quickly the power is added. I'm paraprashing this from a post that Rod made a few months ago. I'll dig and see if I can find it again as to give everyone a better idea of what is happeneing.

Suffice it to say that when you are increasing the power with the first setting, you're increasing both horsepower and torque with that setting.

bigblock2stroke

peak torque and peak hp occur at different speeds, so if you are running 3 torque and 1hp, the computer will adjust the peak torque at lower speeds to whatever corresponds to 3 torque and will also adust hp at higher speeds to whatever corresponds to the 1 hp setting.

You are correct that the torque at whatever hp setting will change when you change the hp setting, however, it doesn't necessarily mean they changed anything in the peak torque range which happens considerably lower in engine speed.

LinearX

https://www.dieseltruckresource.com/...threadid=39119

Go to that thread, then page 4. I think Rod's post is the 3rd from the bottom which give a brief description of how the HP/TQ settings on the TST work. I'm still looking for the one that gives a more thorough run down.

https://www.dieseltruckresource.com/...ock+clutch+800

Go to page 2 and read Rod's 4th post on that page. It's the more indepth description of the HQ/TQ settings on the TST. As an aside, you can go to page 3 and read Got Toruqe?'s first post and there is quite a bit of info on the power the box makes.

I'm done with research. Happy reading.

doug

TSTs use of torque and power is really correct in the mathematical sense. Essentially, the TE setting adds torque, and the PL setting governs how that torque is applied across the RPM range. to understand what this means, note that:

1. Torque is literally the force pushing on truck, regardless of how fast you are traveling. it is unrelated to speed. It is the seat-o-pants feel.

2. horsepower is simply an expression of how fast the engine turns (RPM) while it delivers the torque. mathematically, it is the product of torque and RPM.

So "TE" adds fuel by adding a certain amount of injector duration, and this provides torque per (1) above. "PL" controls the total power output by limiting (2) as described above.

GeorgiaCracker

The torque/horsepower relationship is beginning to reveal itself, but I still need some operational examples to grasp the performance effect.

For instance, if I set the power on 1 and the torque on 9, how would the truck perform under full acceleration?

Similarly, if I set the torque on 9 and the horsepower on 1, how does the truck perform at WOT?

Better examples: what is the best setting for acceleration from 0-60 MPH? How about from 70 to 110 MPH?

doug

I would expect the truck to pull hard at the low end, and then quickly taper off as RPMs increased. This is because the low HP setting acts to limit fueling at high RPMs

That depends on engine rpm. WOT at 1200 you will be making lots of torque and the truck will make smoke and pull hard. WOT at 2900 RPM it will pull slightely harder than stock.

if you mean horsepower on 9 and torque on 1, then I would expect this to produce a small increase in torque that carries through well into the higher rpms. This would produce a torque curve that looks a lot like the stock curve -- broad and flat, except higher.

Well, in order to accelerate, you want a broad torque curve with lots of area under the curve. That means give it all you've got -- 9/9.

Basically I think the concept you may be struggling with is that the HP setting on the TST acts as a limiter, and the Torque setting acts as the fueling source. The box will deliver the fuel according to the TE setting, as long as the product of torque times rpm (set by the horsepower setting) is not exceeded. The HP setting has the effect of allowing torque at the low rpms, but limiting enging output at the high rpms. Rod correct this if necessary.

see the fueling_box_summary for more details on the HP and torque discussion.