Episode 1: [LINK]

This is the one I was dreading for years, and I started to write a novella on this - but I changed my mind. For those following along with the PID 3D saga, many will understand what they are seeing here - so I'll just let the data do the talkin'....















I have a ton more to add to this, but I figured I'd give myself a break, and you a chance to digest this and ask questions.

 

Teacher! Teacher! I have one!

Please forgive me for my lack of knowledge, I am a decrepit old man who never liked school in the first place so I'm a little slow on things. I see what looks like FIPW's waaaayyyyyyy above that 3.2ms line of destruction. I mean...to me it looks like it's dancing up in the 50ms range. Am I seeing it right or am I not understanding what I'm looking at? It is a shame that EGT's can't be added to it but that's the way the cookie crumbles.

 

You nailed it without me saying anything - it's the FIPW, it's the FIPW, it's the FIPW.

5 ms is the same as 5000 microseconds - so it is approaching 5 ms in the data.

 

OK... say someone says "But Tugly, I have the same problem and I've been told a T500 HPOP can fix it". To that I say "here's the money shot". Same truck after a Buck$Zooka blast and some wrenching:



Please note the improvement - but not the fix! I came up about 700 PSI ICP, but the target is 3000 PSI ICP - so I'm still down 500 PSI ICP. Also note my IPR is still elevated beyond the ideal 40%, but it is another improvement - barely (it was still climbing when I let off). The Stinky Spike is more subdued, but it's still there.

I'm still waiting for the ultimate question... and I'm still looking for the data in my library to answer it.

 

I probably shouldn't. So I'll...

 

OMG, DATA!

Subscribed

 

Your only seeing one bank of ICP. Wouldn't a HPX give a more accurate reading, unless that is, you have one installed.
. Incorrectly installed injector?
A bad injector?
. Fuel delivery?

. Your seeing high % and high ICP, just like me, but mine traps out at 64%. Still need to do the Cody test, even though I already bought orings😉

 

The T500 has no check valves on the outputs, so it's like an HPX (both sides get the same oil). Besides, it's not like one side will get 3000 PSI ICP and the other side gets 1800 or 2500 PSI with a stock HPOP. Remember - the ICP reached 2800 PSI ICP just fine without raising IPR in the stock tune. Could this have been an injector problem? That's the question many tuners are asking... and I can get deeper into that later. For now, the question is if reducing the FIPW would allow the ICP to reach full pressure without skyrocketing EGTs and IPR - yet get better performance than the long FIPW. The answer is yes... but I'm still on safari for that collection of data. It's not like I lost the data - but I have waaay too much to find anything quickly.

In the case of skyrocketing IPR and sagging ICP on a stock tune with low FIPW - that's likely an oil demand/supply/command problem.

 

I have a question, more like an observation. If it's not the one you're looking at it's one you (we) should be. It's right there, almost glaring at us.

 

Fire away. Not everybody sees this the same way.

 

FIPW, in ms. RPM is Revolutions:Minute. As RPM's increase FIPW should be decreased proportionately. I can only imagine how far through the ignition portion of the cycle that fuel is still being pumped into the cylinder at 3000 RPMs. Am I seeing clearly?

 

I would not think so.
3000RPM = 50RPS = 50,000 ms/rev
How about 139 ms/deg. we have time!
The FIPW does not have to be adjusted for RPM unless my math is bad (and it could be).
U do the math.

 

The problem is that I get lost in the math. What I see is that 3.2 ms is the limit and based on Tugly's demonstrated visual somewhere anything more than that has fuel entering too late. The logic tells me that at 3000 RPM's it would put that piston 3x further away than it would at 1000 RPM's. Now...I guess I should have asked at what RPM's was Tugly's visual representing. If that is at 3000 then my logic does not apply.

Edit: Studying your math it does make sense.

 

1000 ms = 1 second, so .001 seconds = 1 ms.

3000 RPM = 50 revolutions per second

1 second divided by 50 revolutions = .020 seconds or 20 ms.

20 ms per revolution (360 degrees of travel). In 5 ms, the piston has run away from the flame, using half of its full travel. Fuel applied near this stage makes a slow, smoky burn - instead of an explosion (think 200 PSI compression instead of 400 PSI - and the oxygen is used up by the earlier fuel).

When dealing with nozzles, pressure multiplied by time open (3000 PSI ICP x 3 ms) = a fixed quantity of fuel. Less pressure or less time equals throttling back. Throttling back with RPM increase isn't the goal in a WOT scenario.

Reduced ICP means it takes longer for the fuel to sneak past the nozzle - and the longer FIPW means the fuel is applied until late in the cycle, and heat ensues. Think brushing your hand past a flame vs. parking a lighter under your palm.

Keeping the ICP and FIPW constant throughout the WOT run means you get a constant quantity of fuel applied through the RPM range.

 

OK, I've cyphered all that out and see where ICP drops and FIPW goes up in that chart up there. So...what causes the drop in ICP? I see that ICP DC goes up at the same time that it is happening.