midnightoil
Veteran Member
- Joined
- Feb 18, 2013
- Location
- Minnesota
- TDI
- researching for a TDI highway driver and occasional tow pig
To be clear - this is not yet an engine/vehicle I yet have, just one I am planning. Vehicle would be an 01-03 Jetta and engine an ALH or ALH/BHW hybrid.
So i'm slowly narrowing some of my interest and focus... people sort of have me sold on the idea of using a GTB1756 turbocharger for a possible future build, because it seems to have enough upper end potential (suggested 220bhp) that I don't think i'd need to crave much bigger.
If I understand diesels right though it's more an airflow limitation, so should I assume that turbo at 220hp on an ALH/BHW hybrid is the max power before black smoke and problems no matter what I do? (ie whether or not I use a huge intercooler, water/methanol injection)
My assumption is that NOS should put extra oxygen into the combustion chamber, potentially supporting the methanol injection for another 40hp temporarily or so. I think the idea of 220bhp sustained and 260bhp for brief spurts matches all I could want.
I assume the injectors sized for 220hp in a little 1.9L engine would probably do more to potentially impair driveability or MPG than a larger turbo. (and am curious if this is the case/is this too much HP to still be a good tow machine and highway MPG and year round driveability?) I mean this would be like a 660hp Cummins 6bt, driveability of those suffer by that power at least mechanical versions.
Is there any reason for the 1756 turbo if i'm using smaller injectors for now vs using the factory turbo? At what engine HP should I jump from factory turbo straight to the 1756 and do I have to upgrade everything else as a package at the same time, or is there a benefit of just boosting turbo airflow with a turbo upgrade alone for awhile even if I didn't do injectors and such right away? (like lower EGT)
So i'm slowly narrowing some of my interest and focus... people sort of have me sold on the idea of using a GTB1756 turbocharger for a possible future build, because it seems to have enough upper end potential (suggested 220bhp) that I don't think i'd need to crave much bigger.
If I understand diesels right though it's more an airflow limitation, so should I assume that turbo at 220hp on an ALH/BHW hybrid is the max power before black smoke and problems no matter what I do? (ie whether or not I use a huge intercooler, water/methanol injection)
My assumption is that NOS should put extra oxygen into the combustion chamber, potentially supporting the methanol injection for another 40hp temporarily or so. I think the idea of 220bhp sustained and 260bhp for brief spurts matches all I could want.
I assume the injectors sized for 220hp in a little 1.9L engine would probably do more to potentially impair driveability or MPG than a larger turbo. (and am curious if this is the case/is this too much HP to still be a good tow machine and highway MPG and year round driveability?) I mean this would be like a 660hp Cummins 6bt, driveability of those suffer by that power at least mechanical versions.
Is there any reason for the 1756 turbo if i'm using smaller injectors for now vs using the factory turbo? At what engine HP should I jump from factory turbo straight to the 1756 and do I have to upgrade everything else as a package at the same time, or is there a benefit of just boosting turbo airflow with a turbo upgrade alone for awhile even if I didn't do injectors and such right away? (like lower EGT)