Best Mods for Torque?

[Northboundtrain]

The more I learn the less I know . . .

I've been reading this forum voraciously and posting the occasional question in preparation to rebuild an engine for my '91 Jetta ecodiesel.  

This is my goal:

More Power (of course).  I'm not so interested in quick acceleration, drag racing, 1/4 mile, etc.  What I want is to be able to get up the mountain passes around here without downshifting into 2nd gear and seeing a line of angry RVs in my rearview mirror.   I think this means increasing torque mainly.  

My plan was to rebuild an extra 11mm engine that I have in the garage.  I was going to put in oil squirters, turbo pistons, and add a turbo.  Now I have learned that turbo blocks have different cranks and main caps, and that the turbo heads have different valves and pre-chambers.  So I'm rethinking my plan.

It would be nice to keep the car operational while I chip away at the engine rebuild project, but perhaps I should pull the ecodiesel engine and work with that.  It seems that the later block would give me more options (hydraulic head, 1.9 head, etc.)

Many of the mods I read about here (e.g., governor removal) seem to be aimed at increasing rpms and horsepower, but like I said, I want hill climbing ability, and that means more torque.  (But I guess being able to sustain higher revs without overheating would help too).

At a minimum I plan to open up the intake, build a custom exhaust header, do a port-polish-match job, turn up the fuel screw, get an egt, and add an oil cooler.  

I know a turbo would also help.  I guess I'm wondering whether the bang for the buck is worth it, and whether I'm likely to harm my shortblock if it isn't a factory turbo to begin with.

One mod that really intrigues me is somehow stroking this engine (I seem to remember a recent post on this topic, but I can't find it now).  Could I use a crank from a 2.0L gasser and machine the rods and/or pistons a little shorter?  That would gain me another 100cc!  I'm more than willing to be the guinea pig on this one.

Would the pump/governor mod be worth it?  What about the injectors -- pop pressure, orfice size, etc.?

I guess what I need most is better direction given my specific goals.  The more I research, the more options and possibilities I learn about, but also the more potential problems and incompatibilities.  

So assuming I start with this '91 ecodiesel engine, what can I do for better torque and possibly higher sustained revs?

I'm looking forward to getting going on this project, and I really appreciate any help.

[935racer]

The post you are thinking about was about DE stroking a 1.9. Its not as easy as just machining down the rods, you need completely different rods, and they would be custom and expensive (800-1200USD). Your best bet for low rpm torque would be starting with a 1.9TD, they are very torquey stock, and if you do the governor mod, turn up the fuel and use a custom cam to get the turbo spooled up really quick it would make for  nice hill climbing car. Intercooler, oil cooler are a must. Climbing hills really beings up your egts. Getting the head flowed and a good valve job is imoortant too and upgrading intake manifolds makea s big difference as well.


All this said building a flat out HP monster is still gonan crete a lot of torque as well, but the further you push things to the limits the more often they break down.

[Northboundtrain]

I'm afraid that a 1.9 isn't in my budget at the moment.  Maybe a 1.9 head, but only source I know of for a longblock is Z&S imports, and he wants several thousand for a running takeout.  Is there another source for one besides getting extremely lucky at the junkyard? (I'd have a better chance of winning the lotto around here)

Just out of curiosity, why would I need custom rods?  Is it not possible to shorten the 1.6 rods by re-machining the crank journal bore a few mm toward the piston?  Then maybe take a little material off the top of the piston?  Has it been tried?  A "1.7L Stroker" seems pretty cool.  

Okay, maybe I'm getting carried away.  So are the typical hp and flow mods going to give me all I can get out of this 1.6 ecodiesel engine?  Would you guys mind giving me a quick bang-for-the-buck ranked list of mods I could do to this particular engine?  The pump has the LDA thing on top if that makes a difference.  I mainly want to settle this turbo vs na quandry.  Turbo engines are so scarce around here that if I could make do without one, I would.  On the other hand, if a turbo setup is the only way to get what I want, then I'll just have to wait for one to come along.

[Audi80]

I would start from ī91 engine. Add a big intercooler, bigger VNT turbo, 2,5" exhaust and good pump mods including 10-12mm (8mm in ECO-diesel) plunger. This should give more than double HP and lots of torque. If thatīs not enough, then cam, 1.9 head, headers etc. And of course add a oil cooler.

Does the LDA thing have anything inside? I have seen empty LDA tops on ecodiesels :roll:

[Northboundtrain]

Does the LDA thing have anything inside? I have seen empty LDA tops on ecodiesels :roll:

I don't know.  I'll check into it.  

I think you all are assuming that this thing has a turbo already.  It doesn't.  It is naturally aspirated.  I've heard the term ecodiesel used on this forum in reference to a particular type of turbodiesel.  However mine is not a turbo.  My Bently manual distiguishes between the turbodiesel and ecodiesel, so I assume I'm correct in calling it an ecodiesel because it is definitely different than my other n/a engine, and the pump has the LDA on top.  

This is why I'm wondering whether to a) put a turbo on this engine and modify as necessary to accomodate the higher compression and temps from turbocharging, b) wait until I can find a factory turbo shortblock, or c) keep this engine naturally aspirated and modify it as best I can for more power.

Thanks, keep it coming.

[Northboundtrain]

If yours does not have a turbo it is not an ECOdiesel.  

Okay, then mine is not an ecodiesel.  I guess that means it is just a regular n/a with a hydraulic head and the LDA thing on top of the pump that is serving an unknown function (other than getting in the way of removing the injectors)  So I can probably leave it in the car and rebuild my spare engine.  So keeping the n/a setup, these are the mods I'll do:

port-polish-match
headers and bigger exhaust
opened up intake
oil cooler
governor mod or maybe a rebuilt Giles pump
egt

With these mods what kind of HP numbers can I hope for?

[935racer]

My guess is that you could get over 80WHP that way But that would be witha giles pump. I am planning on building a hot NA diesel one day, but my 2litre 16v diesel is taking up my funds and time right now.  

[Northboundtrain]

Anthing close to 80 hp would suit me just fine.  Maybe for now I'll just do the governor mod and get a Giles pump if I want more.

2.0L 16 valve gasser-to-diesel conversion?  Do you have more info or a post on this project?

[935racer]

Actually it is a 2litre 16v diesel from the factory and a PD no less. We don't have them here I might be bringing in 2 next month for some customers cars. I might make a post about my caddy one day, its got some cool stuff. 2litre 16v PD, tdi 6spd transmission, 11" brakes front and rear, 15x9 3 piece gotti wheels etc

[RabbitGTDguy]

Here is some details on the LDA vs. ADA from the Bosch Diesel Injection Manual that I have handy here with me...

The LDA


The ADA


The two are actually very similar in design with the exception of their source signal and end operation. I think it'd be interesting to open one up It wouldn't be hard at all for you to swap the TD LDA onto your pump. Let me know if you need more help.

Yes, 935Racer, it'd be interesting to hear more information about your 2L 16v PD MK1... Simon is doing one in Europe but there hasn't been much info on his yet either. I was particularly interested in the design of the pistons on the 16v...from the pics I've seen, they have no lip.
Hope your gov. mod for the 4bt pump  is going ok that I gave you info on for that customers car... did you decide to use the pump? Didn't hear back after you asked and I had replied about how the cams were performing...it'd be cool to see info on that as well...

Joe