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Discussion Starter · #1,141 ·
This looks like a lot of work...


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IMO using a angle grinder or that sort of item to cut the line can be bad, i use big cutters for my teflon braided line, if u do use a angle grinder type cutter make sure u clean out the hose as all that extremely fine dust goes into each end of the line and trust me when i say it will kill your pumps and or injectors if it gets into them, to clean out i run water thru the line then make sure it dries out or u could use petrol if using it as a fuel line run it thru filter and back into a container, thats why i use the big cutters as u dont get any find dust issues
 

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Discussion Starter · #1,145 ·
I have a cutter, and plan to flush them out regardless. Thanks!
 

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Discussion Starter · #1,147 · (Edited)
I removed this post as I believe it to be in error, regarding "raising" the High Flow upper limit values in the FPCM. I'm not sure exactly what the variation was, but it could be a combination of raising pump duty cycle and my fuel flow so easily exceeding the HF Upper values that it was nothing more than a correlation.
 

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Discussion Starter · #1,149 ·
I feel like you're just trying to talk yourself out of putting all those fittings and hoses together.
Well...



But yeah - going to pulley up and probably intercooler everything, so those fittings are going to get fucked no matter what. "20 psi" just has a nice ring to it....

But judging from the IDC on the second graph, I probably could have lived with it as-is. Adam's/ ALM fuel hat and the DW pumps with the Aux kit are getting it done!

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Discussion Starter · #1,150 · (Edited)
I cross-posted this in my tuning thread, but it seems that raising the High Flow upper limits is actually the wrong thing to do!

151017


There are two increases here in actual (and desired) FP with excellent correlation: my baseline FP is ~50psi, which is what most of us see driving around town. Ordinarily, when we floor it we see a jump into 70psi - but not here. There is an intermediate step up to 60psi before I eventually see 70psi. This intermediate mode - where the ECM is pulling duty cycle to bring actual fuel pressure DOWN to the commanded 60psi - is what I believe I have been seeing all along.

What's happening is that my fuel flow rate (in lb-hr) is so low under normal driving, that we are typically in "Low Flow" mode in the tune (50psi). Most bolt-on cars will use enough fuel that with the low setting from OEM, when you mash it your flow rate jumps so much that you simultaneously clear the "low flow" mode threshold, bypassing "Normal" mode altogether and going straight into high flow mode (70 psi); so it looks like in stock form our commanded fuel pressures jump from 50 to 70 psi, when in reality the FPCM could have stepped up from 50 to 60 to 70psi.

Only after raising my "high flow" upper range as was suggested elsewhere, did this manifest into that "fuel pressure dip" I see when on Ethanol - due to the vastly altered fuel flow changing how I triggered each mode: Low flow when tooling around, then "Normal" mode in the lower RPM range under WOT - which allowed for pump modulation - and then "High Flow mode higher in the RPM range. The dip in pressure was "Normal" mode.

So I'm going to LOWER my high flow Upper limits, so that I trigger the High Flow fuel pressure earlier - whether on pump or ethanol - and monitor to see if FP DC is still being pulled or if it stays at 100% - or in other words, my theory is that the primary difference between "Normal" and "High Flow" modes is that "Normal" mode allows pulse-width modification and "High Flow" mode doesn't? I hope to verify this soon.

ETA: Verified below!
 

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Discussion Starter · #1,151 ·
Success:

High Flow mode commands 100% duty cycle. So for max pump output, you want to LOWER your High Flow upper threshold.

I changed mine to 300 lb-hr just as a round number, and my log shows going into "Normal" mode at 60 psi early in the run, with pump duty cycle being modulated, and as soon as I hit 300 lb-hr the line pressure increases (overshooting commanded) with 100% pump DC. This occurred almost 1k RPM earlier than the run I posted above, solely due to High Flow upper limit adjustment.

It can be hard to see, but the Fuel Pump Duty Cycle (white, second-to-bottom frame) steadily drops down to 50% duty cycle in "Normal" mode @60psi, as the ECM tries to match the commanded FP. As soon as my flow trips the High Upper threshold, it pegs to 100% DC and does not drop down. The tapering of fuel pressure towards the end of the pull is due to consumption, pump DC remains at 100%.

151025
 

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Discussion Starter · #1,152 ·
Fuck. These braided lines are a bitch! Lol

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Discussion Starter · #1,154 ·
Once you have a couple pieces done it’s not too bad.
Yeah, I did three today no problem- I just realized I'm a few fittings short and I'm trying to avoid really short hose lengths. Taking my time to hopefully measure thrice and cut once!

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Koul tools makes it a lot easier.

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I installed a thermal heat sleeve from the bottom right brace to the fpr inlet behind the supercharger to keep the header from heating up the fuel on its way to the engine. If you notice, the stock fuel line has a heat sleeve there too. I figured it can only help. I used this one -> JEGS 32013: Thermal Heat Sleeving 3 ft. Length | JEGS
im doing same on my build fuel lines all covered in heat sleeving im even going to do the rails, some people wonder why some make more power then others and doing all those 1%ers add up and thermal protection goes a long way if done right
 

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Discussion Starter · #1,158 ·
Yep I have some from the header install I was going to use.

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Discussion Starter · #1,159 · (Edited)
So.... surprisingly, the lid doesn't leak.

But the brick does NOT like 19psi. That is fin deformation that matches the blower opening pretty well on the underside (facing the rotors). The top (exit) of the brick looks perfect!

Going off this, I'd say ZL1 lids are not ideal over 15-16psi.

Could also be the larger rotor packs of the 2650 creating a more abrupt transition to high flow contributing to the deformation. Hopefully the Kong lid proves itself.


 

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So.... surprisingly, the lid doesn't leak.

But the brick does NOT like 19psi. That is fin deformation that matches the blower opening pretty well on the underside (facing the rotors). The top (exit) of the brick looks perfect!

Going off this, I'd say ZL1 lids are not ideal over 15-16psi.

Could also be the larger rotor packs of the 2650 creating a more abrupt transition to high flow contributing to the deformation. Hopefully the Kong lid proves itself.


Oh snap I haven’t seen one that bad.
Could it be caused by anything else? It seems hard to believe it was just air that did that.
Do you spray meth Pre blower at all?
Could water or anything have gotten in there?


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