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Why does nobody swap the 1.9 ALH into older full size trucks?

12K views 8 replies 7 participants last post by  Whitbread 
#1 ·
In the course of lurking on this forum, I have read a lot of great threads about swapping the 1.9tdi into all sorts of Jeeps, Rangers, Toyotas etc. However, nobody ever seems to put them in, or even consider putting them in anything larger. If something is never done, there is usually a good reason for it. I am curious what that reason is.

Now, before you launch into typing something akin to "that will never be able to move something bigger than a Wrangler, you need a 4BT..." let me explain what got me wondering this:

People seem to regularly build 1.9's to produce around 130hp and 240lb-ft and higher with little concern except $$$. These numbers also happen to be the numbers the 6.2 Detroit diesel put out that GM shipped full size K1500's and K2500's with (at least according to wikipedia), and the 6.2 weighs at least 150lbs more.
While few laud the performance of the 6.2, it gets the job done. So what makes a 130hp 240lb-ft 6.2 adequate, but a 130hp 240 lb-ft 1.9tdi unacceptable (assuming gearing well suited to each)? Is there some power/liter "density" that changes the equation?

This is purely theoretical. I am not about to try this, so there is no need to dissuade me or anything. I'm just curious, and would love to hear what you all think.
 
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#3 ·
I have a 2002 Jetta with the ALH motor. Currently it's stock, but new turbo and injectors and tune will be here soon. With my setup I should make around 165-170 hp and roughly 300 lb ft. From what I've heard peak torque is around 1900 rpms. I plan on putting the engine into a 1984 CJ7. Should be fun.
 
#4 ·
A couple of years ago Dougal worked up this for me, It was for a '67 Jeep Wagoner that would live at 6,000'



Quote Originally Posted by Dougal
Best I can do with wastegated compounds

GT1544 Garrett with 0.34 A/R turbine housing (p/n 454082-2) and Td04-13T (or Td04L) with 6cm turbine housing.

Wastegate the TD04 to ~14psi.
Wastegate the GT1544 to ~35psi

Should deliver ~410Nm at 2000rpm and 98kw at 3000rpm tapering off a little to 90kw 4000rpm.
All at ~2000m altitude.

These are mapping out quite nicely. Garrett is in it's best efficiency early. MHI is in it's best efficiency at higher rpm.

You'll need airfilters capable of 300CFM, injection pump set to ~85cc/1000 shots, a big front mount intercooler and this should be a clean tune at 18:1 A/F.
 
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#5 ·
Torque peak on a 1.9 ALH is around 1900RPM but it will drop off a cliff just below that when doing real work. Keep in mind a 6.2 has alot more mass and inertia to help keep things spinning. In a heavy truck Tdi setup(4000lbs+) you want to plan for cruise RPM around 2700 to 2950 to keep the EGTs happy. Perfectly sized compounds help greatly just like any diesel setup. A 1.9 Tdi will do the work but everything must be matched up well.
 
#6 ·
Thanks for the interesting replies! Motohead1, I'm still reading up on the details of egt's and how to manage them. Could you explain how you arrived at the 2700 to 2950 rpm number? Is it basically that the faster you are moving air through the engine, it cools the exhaust gas temps? I would have thought you'd be best off being at the peak torque rpm while cruising.
 
#7 ·
RPM suggestion is just based on experience and what many others have concluded before me. Many factors. EGTs, Waterpump flow, EMP,... even aerodynamics. For a full size that would be used for any towing at all I would opt for a little bit larger displacement. An OM606 or OM648. Empty or just light bed hauling a TDi works great. My 4300lbs dakota with 4.56 gears moves along fine with a bolt on ALH. But I would not want to tow more than 5000lbs
 
#8 ·
I own a car with a 2.0 BMM TDi. This is an 8V pump-deuse motor which is effectively a 1.9tdi with slight overbore and a better turbo (GT1646V).
It's factory around 103kw and 320Nm and it pulls well from about 1500rpm (peak torque was at 1750rpm). Getting 20% more is just a tune away.

The reason I mention this is the GT1646V turbo (it's built into a manifold) should bolt straight on to most, if not all, 1.9 tdi 8V motors. Allowing that 130hp, 240 ft-lb target to be done with basically factory parts.

I think the big reason no-one swaps them into older full-size trucks isn't the power or torque. But more you can fit two of them into the engine-bay. One would just look lost!
 
#9 ·
I have a compound turbo bhw tdi in my 00 ford ranger making about 210whp/375wtq. It weighs 4200lbs with me in it. I've grossed over 10Klbs a handful of times towing/hauling and it has moved it just fine. Any kind of 1/2 ton truck would move perfectly well with it if you weren't trying to tow 8klbs all the time. Gear it to be at 2600-2900rpm at freeway speed, have a big intercooler, good radiator, and bigger air/oil cooler than stock water/oil cooler.

With the compounds, towing a 98xj loaded with wheeling gear on my 20' aluminum trailer, at 65mph I run 32-35psi of boost and 950-1000F egts on flat ground at 65-70mph.
 
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