excellent work malone.
Most readers tend to assume that the person presenting the information about a project is the person who did all the work on the project. I want to be clear that I can't take all the credit for this 1.6TD project. It would not be possible without Passenger Performance
they deserve more credit.
jtanguay: That's how diesels are tested here as well. It's also known as an opacity test.
I Gteched the TD on dry road an hour ago. During my previous Gtech plots (shown on first page) I had injectors w/ GTD nozzles and higher opening pressure. Now I have smaller OEM injectors because we were trying to diagnose the low RPM white smoke issue. The pump's fuel screw was also turned up recently. The peak HP really isn't at 5,000 RPM - it's more like around 4,800 RPM.
The green and blue lines are two runs from before.. one of these runs were already shown in the first post of this thread. The black and red lines are from today.
The recent Gtech plots confirmed my suspicion that the turbo indeed spools up slower now, which I find odd. However, after 3,200 RPM, holy crap the power/torque picks up real quick. Woo! what a ride
It felt a lot like having a larger turbo now but I still have the same turbo with no change in boost control. Quite odd. The low boost/torque during lower RPM explains why I have grey smoke - the grey smoke is not just because of the fuel screw being turned up.
So why the turbo lag? Could it be because I downgraded to OEM injectors from GTD injectors? Highly unlikely. Could it be because we adjusted the fuel pump timing? Or could there be a small leak in the charge piping? There's still more tuning to come. Will check for boost leaks, etc. and then Gtech again when GTD injectors are reinstalled.
*edit; during daily driving in the last couple days I did notice less power below 3,000 RPM but it didn't feel significant. The car's still perfectly comfortable to drive in traffic with this power curve. However if I need accelerate quickly I did sometimes see a small puff of grey smoke @ low RPM because of less boost available.