Ahu mTDI question using Land Rover pumps

[Sohio]

I started with an 82 Rabbit n/a. 50k original miles however motor was hit.
found a 98 jetta with a blown head for $500.
got a new casting with new cam, sewed it up and the timing gear spun, causing the cam to end itself as well as three lifters.
installed new timing gear & lifters along with original cam which looked pretty good considering the Jetta has over 300k!
also had the injectors remaned and fitted with bosio nozzles.
took it down the road a few times and it blew a hard fuel line .snapped about an inch about the injector.
the Jettas body is toast BTW. but it came with the engine.
new lines are in the mail.... now my question.

the ahu is destined for the rabbit but I want to convert it to mTdi .
I would like to use a 200 tdi or 300 tdi from a land rover.
is there any major differences. ?
I understand the 6th digit in the part number indicates the size but this one is different from numbers ive seen referenced.
 will this one bolt up  ?
http://www.ebay.com/itm/ERR4419-DIESEL-INJECTION-PUMP-300TDI-RECONDITIONED-LAND-ROVER-DISCOVERY-1-/371114981870?pt=LH_DefaultDomain_3&hash=item56682d39ee
thanks yall pictures. soon .

[libbydiesel]

That's the pump you want to use.  You do need to have the pump bracket machined, though.

[Sohio]

That's the pump you want to use.  You do need to have the pump bracket machined, though.

hi libby thanks for the info 
other then having the bracket machined is there anything else necessary to have on hand to install the pump?
will the ahu sprocket work as is? or do I need an alh ? 

also do you think I should be worried about the 300k miles on the bottem end?
im eager to go on with the build but after the gear shearing and the line breaking im starting to think its a bit precarious to move forward without replacing anything crucial to the health of the engine. 

[vanbcguy]

If you've impacted valves but haven't replaced them you have a ticking time bomb. From your description above it sounds like you had to replace cam followers but I don't see mention of the valves themselves. If they were not replaced you probably have another 1000 miles before you're looking for another head.

As to the Rover pump, you need to sort out a bracket for the accelerator cable, you probably want the delivery valves off a VW and ideally you want an ALH sprocket and hub. You also need to sort something for the pump mounting bracket below the pump head.

[Whitbread]

I just put a LR300TDI pump on my ahu in my MK1 rabbit so I can give exact info of what I did.

- Bore out pump bracket for larger snout
- I trimmed my 1.6TD throttle cable bracket and tweaked the throttle lever to give me a workable connection. Transferred ball over frm 1.6TD pump for cable to snap on to and dtilled hole in throttle lever all the way out.
- 10mm ETDI delivery valves
- As for the sprocket hub, some fun things here. The LR timing lock pin locks the pump at cyl #4 TDC, not #1. Found out the hard way haha. The LR pump hub will work with an alh pulley if you have a lathe. If no lathe, then you must use an ALH pulley hub. To use the LR hub, you'll have to scribe the location, drill and tap an M8 hole (LR hole pattern isn't symmetrical like VW pattern is, have to add one hole. You will use this new hole to time pump at TDC #1 as it ends up being exactly 180* from the notch in the hub), then lathe about .150" off the hub to pulley mating face of the LR hub and lathe about .100" out of the inside of the ALH pulley to get belt offset right. When you cut the pulley hub, make sure to get the pilot bore for the pulley correct for the ALH; the LR pulley uses a smaller center bore. When you face the .150" off the hub, it will give you enough material to make a new pilot for the pulley.

If any of that was confusing, I can snap some pics to help.

From there, do you standard aneroid pin shaping, and tweak fuel screw up a turn or so and drop you idle to match. Mine runs pretty good so far. I still much prefer the Etdi experience, but for a daily beater shop truck the Mtdi setup will be fine.

[libbydiesel]

I wouldn't recommend 'shaping' the Land Rover LDA pin.  It is optimally shaped from Bosch.  Any further shaping is damage.   

I have a couple well-tuned mTDIs and a stock eTDI.  I really don't see a difference in the experience other than a slight change in idle speed cold/hot on the mTDI and the eTDI being slightly more clattery.  Any other differences I can detect are due to bolt-on components that have nothing to do with the engine management.   

[Whitbread]

I wouldn't recommend 'shaping' the Land Rover LDA pin.  It is optimally shaped from Bosch.  Any further shaping is damage.   

I have a couple well-tuned mTDIs and a stock eTDI.  I really don't see a difference in the experience other than a slight change in idle speed cold/hot on the mTDI and the eTDI being slightly more clattery.  Any other differences I can detect are due to bolt-on components that have nothing to do with the engine management.   

How is shaping the LDA pin any different than shimming the high speed governor springs? Changing the camplate? Changing delivery valves? Are those damaging also? Since we aren't running the pump in it's oem application, all application specific oem engineering goes out the window. A LDA pin (such as this one http://www.dennytperformance.com/FuelPins/index.html), gov spring/mod, and turning up the main fuel screw are the oldest tricks in the book for a VE pump.

Without the ground fuel pin, my rabbit was a pooch compared to an electronic ahu with the same turbo and nozzles and a 10mm pump. If I turned the fuel screw to get the power to where it should be, the rpms would hang on the way down and cause an infinite automatic cruise control condition. So, with ground fuel pin and fuel screw backed out to where it doesn't cause hanging rpms, the power is now where it should be.


A stock ETDI is a completely invalid comparison to a hopped up and tuned Mtdi. Hop in a well tuned 240hp ETDI and then compare driving experiences. How much time did you spend tuning the MTDI? I have at least 4 hours in mine if not more. In that time frame, I could've burned a set of chips and driven 3 hours to my cabin and been out on a dirt bike riding already. I can't even remember the last time I drove anything close to a stock Etdi, let alone one with even a stock turbo on it. The higher your HP/L gets, the nicer ETDI is. My B4V with compounds, 15:1 CR, 12mm pump, 5x.013" nozzles, and haldex awd would be a competition only vehicle if it was mechanical. I can stand on the pedal anywhere in the rpm range and it will only haze at absolute most. On the dyno it made 291/472. Anyone can hop in and drive it and if they never step on it, they never know anything is different.

I'm not trying to come off as an mtdi hater if anyone gets that impression. For certain applications, MTDI is fine and dandy. It's the route I went myself for my 81 caddy when the 1.6 let go. It's just a driver/junk hauler. I should about 150hp/250tq with fuel and air as it sits, and it's a hoot to drive. But if you've going for over 200hp like 3 of my tdi's are, the electronics definitely give a much more usable driving character for a street vehicle. Sure you can theoretically make the same max power with electronic or mechanical, but the electronic will be far more civilized. Look at the diesel truck world; 10 years ago, 1000hp streetable trucks didn't exist. Now, I have 4 local customers with over 1000whp on 24v CR cummins setups that I regularly see their wife's driving.

[libbydiesel]

Shaping the LDA is different from shimming the governor because it is a step in the wrong direction as far as pump adjustment/adjustability.  It makes the pump un-tunable.  The linked LDA pin is a kluge at best.  Someone would probably have an easier time just running a non-aneroid pump, cranking the max fuel up and 'tuning' the smoke on-the-fly with their right foot and an eye on the rear view mirror.  The LDA pin is an intentionally eccentric grind that allows you to tailor the boost/fuel curve by rotating to a more aggressive angle for more fuel at higher boost (or less smoke at lower boost) or to a less aggressive angle for the reverse.  Once ground you destroy its adjustability.  Grind away on the AAZ 'joke' pin, but the LR pin is better stock than you'll ever make it with a grinder.

If you turned the max fuel up to the point where the rpms hung than your idle was set too high.  If you ran out of idle adjustment then your accelerator lever to shaft orientation was on the wrong spline.

I have spent a tremendous amount of time tuning injection pumps in general.  On any given injection pump for a given max boost pressure if starting from a completely disassembled injection pump without any settings 'saved' (won't idle, max fuel off the map, revs out of control, lda completely out of whack, etc...) it usually takes me 2-3 hours of tuning to get it very well dialed in.  Once dialed in to a reasonable tune, adjusting for minor or even significant changes in max boost/power can be done very quickly without any untoward smoke off-boost.

Both of my mTDIs are just as 'driveable' and have just as 'civilized' and 'usable character' as my eTDI.  I'm not sure what to say about yours if it isn't.  I guess all I can say is good luck with it.  Probably a lot of it has to do with the ruined boost pin. 

I'm not an eTDI hater either.  I love mine and don't have any plans to convert it to mTDI any time soon.  I also find that most of the folks who think the way you do about mTDIs are the same folks who grind boost pins. 

[Whitbread]

Shaping the LDA is different from shimming the governor because it is a step in the wrong direction as far as pump adjustment/adjustability.  It makes the pump un-tunable.  The linked LDA pin is a kluge at best.  Someone would probably have an easier time just running a non-aneroid pump, cranking the max fuel up and 'tuning' the smoke on-the-fly with their right foot and an eye on the rear view mirror.  The LDA pin is an intentionally eccentric grind that allows you to tailor the boost/fuel curve by rotating to a more aggressive angle for more fuel at higher boost (or less smoke at lower boost) or to a less aggressive angle for the reverse.  Once ground you destroy its adjustability.  Grind away on the AAZ 'joke' pin, but the LR pin is better stock than you'll ever make it with a grinder.

How is the pump un-tuneable now? I still can set the rest position of the pin, set the spring preload with the star wheel, and trim the white plastic spacer if I need further down travel. I'm well aware the pin is eccentrically ground; at the most aggressive ramp angles with the idle screw as low as it can be and fuel screw in as far as it can be without hanging rpms, it wouldn't haze anywhere in the rpm range and was 100% smoke free at wot. EGT's wouldn't even break 800F. A quick throttle snap would give a tiny puff, but that was it. The throttle lever has never been moved from original setting, so I think that's out of any equation there. I took off the TPS and broke the bosch yellow paint on the nut. And yes, the boost reference line is hooked up to the correct port on the aneroid.

Now, with the pin ground to my liking, rest position and star wheel tweaked, I get a reasonable puff if I snap the throttle, a light haze at WOT, and egts peak at 1050F with MUCH more power. The "funny" driving characteristics I speak of have nothing to do with my "murdered" pin, they're all governor or timing control. My boost vs fuel vs smoke curve is perfectly acceptable. My main gripe is the extreme sensitivity of the throttle at low load/low rpm. It can be really hard to keep it from bucking in such a light vehicle in the first 2 gears. I know the condition would be better if I backed down the fuel screw, but that's not worth the power loss. On the 200+hp ETDI's I routinely build, I purposely have my tuner dumb the throttle down below 15-18% TPS to keep the car easy to drive and avoid the condition. It makes a tremendous difference in the the driveablity of very heavily modded car, which usually also have grabby clutches.

If anyone can show me a 250+hp MTDI that anyone's wife can hop in and drive without any complaints of road manners, I'll happily eat my hat on anything I've said. Stock electronic to stock mechanical, I'm sure there's hardly a difference. But not a thing I own is remotely stock so that's not what I'm talking about.

[theman53]

I think his point was that the "throttle" lever was never moved...it needs to be if you are going to get the desired result without grinding your pin.

[libbydiesel]

The boost pin is for tailoring the boost/fuel map.  It is not for adjusting max fuel.  The adjustments required for adjusting max fuel are present on the pump in other ways and using the boost pin to accomplish those results will result in a poorly tuned injection pump.  "When you want milk it's better to milk your cow rather than your horse."  I would describe a ground boost pin as un-tunable because you cannot change the rate of the increase in boost fuel.  The other three adjustments you describe (rest position, preload, total movement) just move the map but you are now 'locked in' as far as pin angle and have no way to change the map.  With the unground pin, you could adjust the rotation to provide an even amount of fuel increase across the range of boost pressure.  If you have too much fuel at higher pressure and too little at low pressure then rotate to be less aggressive - or vice versa.  Once you have the boost fuel curve relatively even, then adjust max fuel so that you have the desired amount of haze across the board.  If, on the other hand, you have inadequate max fuel and try to compensate by increasing the boost pin angle, if you do reach your desired max fuel that way, the result is an under-fueled/under-powered engine any time you are below max boost.

The throttle lever has never been moved from original setting, so I think that's out of any equation there.

I don't see why you would think that adjusting max fuel, governor spring tension, idle, max rpm and grinding the boost pin are all acceptable mods but the accelerator lever to shaft orientation should stay at the stock setting.  The lever to shaft orientation adjustment is there for a very good reason and not making use of it severely limits one's ability to increase max fuel and keep the car 'streetable'.  If that wasn't an intentional adjustment, the lever would not have splines and would only go on one way.  The lever to shaft orientation should always set to the position that allows the desired max fuel and idle but one spline further in rotation and idle backed all the way out will cause the revs to hang and on all stock pumps it is set that way.  If you attempt to increase the max fuel any significant amount from stock you must change the accelerator lever to shaft orientation or you get the hanging rpms and the bucking that you describe.   If you are stuck on keeping the accelerator to shaft orientation at the stock position you severely limit the pump's max fuel.  In fact, you have not maxed out the pump fueling until you have the max fuel screw all the way in bottomed on the pump case (you can even usually remove a couple mm of case material and gain a considerable amount of max fuel).  At that point you would likely need to be a couple clicks from stock in order to maintain a decent idle and avoid the jumpy accelerator and bucking you describe.  I have actually tuned a couple pumps to the point that the max fuel was bottomed on the case (and the case modified for greater max fuel adjustment) and they still had entirely civilized road manners.

With your description of your pump tuning techniques it is no surprise that you are disappointed with the results.  The poor results you describe, however, are not an intrinsic limitation of the mechanical pump to deliver the desired fueling curve but rather a limitation to the techniques you are using in adjustment.  I agree that most individuals would have better results having a tuner do a tune on their eTDI rather than attempt to self-tune a mechanical injection pump but that is apples to oranges.  Apples to apples is the fact that most individuals would do a crap job in tuning their own ECU and a crap job of tuning their own mechanical pump.

[libbydiesel]

I would add that the stock boost pin position/angle is optimally matched to the spring that is with it.  Most often when increasing the boost, the necessary pump adjustments are the max fuel screw, accelerator lever to shaft orientation and idle, and the aneroid is best left alone.  When increasing boost significantly it may be desirable to increase the range of the pin's motion and spring pre-load (done most easily through by removing the atmospheric bleed fitting), but otherwise changing the aneroid is typically an act of detuning.

IMO a too-aggressive boost pin angle is actually worse than a too-mild one.  With the too aggressive angle, the engine is underfueled at no-boost or low-boost which extends turbo spool times and yet is over-fueled at max boost/max pedal making excessive smoke and excessive EGTs.  With a more mild pin slope, you can get a bit of extra fuel at no-boost/low-boost times which can help spool the turbo quickly, but as boost rises, the fuel to air is reduced and the result is low EGTs and no smoke at max boost/max pedal.  To me, that is much preferred.

[Sohio]

I just put a LR300TDI pump on my ahu in my MK1 rabbit so I can give exact info of what I did.

- Bore out pump bracket for larger snout

alright ive got the pump (rebuilt 300tdi) on its way from the uk and the alh sproket and hub coming from NJ.

i was going to get another bracket and have it bored to reduce down time on the conversion but now the second wire has broken from the N108 on the current pump and im just gonna tear it down while waiting on parts.

 side note when the first wire one broke internally i used a very small screw with an eyelet, drove it into where there was nothing to solder, wrapped the wire around the eyelet and solder and it worked. but it would be silly to remove and reinstall again.

ill be pulling the pump today or tomorrow. do you know what the bore amount would be on the bracket if i take it to a machine shop?
thanks again for all the info

[vanbcguy]

Honestly you'd be best to bring the pump in with the bracket once you have it and let them measure everything. Then you'll get back a perfect fit. :-)

[Sohio]

Thanks to everyone and vanbcguy for step by step help in near real time! I got my pump installed today. I don't have a dial gauge but I will tomorrow hopefully. I just eyeballed the position of the keyway on the new pump in referqnce to where the old one was when it was in tdc. This worked at least enough to fire the engine.

Could I be terribly off and still have the car running? I spun the pully completely each way and it appears there may be a happy Middle in there based on how it reacted.
Also I'll be leaving the engine in the mk3 jetta for now so tomorrow I'll be installing a new pedal / cable as well.