Alec

Better start runnin slower -- don't want to muss your hair.

Great job! And just think what'll happen to your times when you start adding more fuel to smoke up all that air you are giving her.

BC847

Well, if I wear a shirt, that'll secure the hair.

It's been a slow expensive road but for the most part, that done to date has been a foundational thing;
- Tightened-up transmission.
- Upgraded harmonic dampener.
- Overall better flowing cold air intake, plumbing, aftercooler, etc.
- Ported head with better valve springs and retainers.
- Combustion pressure better contained with O-rings and studs.
- Overall better flowing exhaust manifold, plumbing, etc.
- Better than OEM fuel supply.

I plan on getting a set of good EDM'ed squirter's along with more air. At this point though I've no clue as to what I'm going to do. A big single or twin spinny things.

I'm gonna go over to Greensboro tomorrow and meet-up with some fellow DTR members for a dyno run. With my luck concerning dyno's lately, it'll be a wonderment if the daggum machine still functions when I back off of it.


All future mods are on hold for the next couple of weeks or so as I've got the wife's 50 year BD and our 17 year anniversary just round the bend.

G1625S

Mmmm, big fat single They're so violent when they light

wannadiesel

EGT still pinned at the end of the pass?

BC847

Oh yes!

Well, I've finaly gotten some reliable numbers for the heap (https://www.dieseltruckresource.com/...d.php?t=197917)

. . . 363 HP with 685ft/lbs torque on #2 . . . ..





And 395 HP with 725ft/lbs torque on #2 and W/M . . . .

Alwaysworking

you water meth adds 32 hp and 40ft lbs if i did my math right

Ilikebikes

I vote for twin spinny things! I may be a little biased, but when that bottom turbo spools for the first time, it's worth ALL the headache!

wannadiesel

Nice numbers, you still have the 190's in there, right?

The correction factor adds about 10 HP too...

Silly gasser dyno operators.

BC847

Nah, DDP4's.

Would I be correct in thinking those HP and torque plots falling on top of one another and peaking together is a good thing?

wannadiesel

Actually I'd like to see it making peak torque earlier and holding the HP line flat for a while at the top end.

Here's a sheet with a more typical curve shape. Pay no attention to the distance separating the curves, that's just the scaling.

BC847

Unit44 was cool enough to have videoed my mess this past Saturday . . .

Alec

The torque & hp curve peaking together indacates that you are still squirting in more fuel as the engine speed increases -- the torque basically indicates how much fuel you are burning per cycle, while hp increases with speed, right? So if your torque curve keeps going up, you are continuing to inject more fuel -- or at least burn it.

The good news is, that she doesn't seem to be starving out at the top . . .

At least that is how I see it -- anyone have other thoughts?

Cool video, BTW!

wannadiesel

I think it's peaking real late, maybe due to not getting the turbo spooled right away. What gear did you run in and what was the procedure?

I think with more tuning and maybe some different operator technique there is more power to be had.

G1625S

The video sounded kinda funny.....sounded like the graph looked, I guess.

BC847

With this dyno event, I removed the TPS assembly from the top of the AFC leaving it connected electrically. With that, the transmission goes into OD VERY early and one pretty-much can't get it to drop out with flooring the throttle. As such, I brought the heap up to 40 (+)mph to begin the run (tach presents with less than 1000rpm).

Flooring it has the engine do the typical ramp-up billowing smoke as the engine begins to come up in speed. A second or so later, the turbo lights and immediately clears the smoke and the engine accelerates on up to 3200rpm (about 120+/- mph road speed I think). You can clearly see/hear it do this in the video. The initial belch of smoke prior to the turbo lighting, then the plume of smoke gets blown out of the way with the turbo coming on-line.

I kind of think the graphs are not fully accurate in illustrating the torque jumping with the turbo lighting. I can see very well the engine jump to the right with the truck twisting a little when the turbo spools.
Further, when I'm drag racing, I'll build 10psig boost and launch in 4wd. Shoving a 6400lb truck 60' in 1.85 seconds seems to contradict the plots.

Perhaps the non-lockup converter is skewing things. . . . ?

There are no issues with drivability. Runs just fine AFAIK. No part throttle issues. 70mph presents with about 700*F ~ 800*F with boost around 8 ~ 9psig. I got 200 miles out of roughly just above 1/2 tank to just below 1/4 tank driving to and from the dyno event.


Frankly, I'm sorta stumped as to what I could tune. I do want to clean up the AFC low boost smoke (I think that's gonna require a different spring) else the fuel screw's in just this side of run-away. Static injection timing is dead on 2.0mm. I do race with the KSB energized.

I think, . . .. I need a lot more air.