I'm getting ready to have an ALH put into my Rocco and was wondering if there's any perks to an MTDI set up over full ALH set up?
ALH or MTDI?
MKIGTITDI
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I was searching for the like button.
Speaking of running stock .187 or whatever they are injectors with a 12mm cummins pump...is that bad? What would happen 8v? I have a great used set of stock and a new in box set of stock nozzles that I really want to use for my MTDI jeep is why I ask.
Yes ... BUT ...
The electronically-controlled pump is capable of regulating the injection timing and quantity (under electronic control). The mechanical cable-operated pump is only capable of manual timing control (the cold-start handle) and it only has primitive injection quantity limiting control (the boost diaphragm).
The electronically controlled pump is capable of, for example, delivering (say) 5 mg/stroke at 2 degrees SOI after TDC at idle (to make it idle smoother and quieter) and (say) 40 mg/stroke at 15 degrees SOI BTDC at 2000 rpm and (say) 40 mg/stroke at 25 degrees SOI BTDC at 3500 rpm (advancing the timing with RPM to account for ignition delay). A mechanical cable operated pump cannot do that. You are stuck with the timing that you mechanically set it up to - no automatic variation with speed and load - unless you feel like playing with the cold-start handle manually while driving ...
The electronically-controlled pump is capable of delivering a different injection quantity with RPM at the same boost pressure to account for the engine's differing breathing capability at different revs - it's all in the mapping. The mechanical cable-operated pump cannot do that. It's capable of backing off the injection quantity when the intake air temperature goes up ... the mechanical cable-operated pump cannot do that.
It's correct to say that the means by which the plunger is actuated and sends pulses of fuels out to the injectors is the same between the mechanical cable-operated pump and the electronically-controlled pump. They are internally very similar.
But it is not correct to say "The fuel delivery, the amount of fuel delivered and the time at which it is delivered does not differ between M-TDI and E-TDI. Learn some stuff before you go spewing incorrect information."
The electronic control makes a big difference ... and it's why VW went to electronic control with the TDI and completely abandoned the mechanical cable-operated pumps. The electronically controlled system was capable of meeting emission standards (at the time) and delivering acceptable noise level and performance (at the time). The mechanical pump could not do that.
I understand you last comment here by the tone, but don't know if I understand if you are saying what I think you are or not. The cable operated pumps advance changes with RPM. The advance mech. is what the cold start lever acts on and by 2,000 RPM or so the cold start does nothing as the internal pump pressure advances it more than the cold start can.
The real point was to say that if the pump is spun by a timing belt so it injects fuel it is mechanical. The ALH TDI I drive has a mech. pump on it. The Mechanical pump is controlled a bit by the electric, but it is still a mech. pump.
The real point was to say that if the pump is spun by a timing belt so it injects fuel it is mechanical. The ALH TDI I drive has a mech. pump on it. The Mechanical pump is controlled a bit by the electric, but it is still a mech. pump.
The centrifugal advance mechanism cannot account for fuel temperature, coolant temperature, and cannot really change the injection timing as a function of the load on the engine ...
While a TDI pump is still a VE mechanical pump at its heart, it is electronically controlled with no mechanical connection to the accelerator pedal, and there's no cold-start handle because that function is handled automatically in the electronics. The electronic versus mechanical/cable makes a HUGE difference to how the engine/pump is installed in the vehicle. The old mechanical pump requires an old fashioned accelerator pedal cable (and the cold-start handle). The electronic pump requires a drive-by-wire accelerator pedal. The mechanical-pump engine can run without any electronics (as long as you can get the glow plugs and starter motor to work, and you need a 9 volt battery for the cutoff solenoid). The electronically-controlled pump needs a wiring harness and ECU and several sensors, including that drive-by-wire accelerator pedal.
If you are building an older vehicle with a TDI engine, there's no question that you CAN make it run with a fully mechanical pump (no electronic control) and it's been done several times.
But if you go to the trouble of re-wiring the relevant portions of the vehicle, the electronic pump control will give a degree of control over the injection quantity and timing (and boost pressure) that cannot be achieved with the completely mechanical pump - if the tuning is right. This is why VW did it this way. Better driveability, lower emissions, less noise, better cold starting, better fuel consumption, etc., as long as the tuning is right - but that "right" level of tuning cannot be achieved to the same level with the fully mechanical pump.
While a TDI pump is still a VE mechanical pump at its heart, it is electronically controlled with no mechanical connection to the accelerator pedal, and there's no cold-start handle because that function is handled automatically in the electronics. The electronic versus mechanical/cable makes a HUGE difference to how the engine/pump is installed in the vehicle. The old mechanical pump requires an old fashioned accelerator pedal cable (and the cold-start handle). The electronic pump requires a drive-by-wire accelerator pedal. The mechanical-pump engine can run without any electronics (as long as you can get the glow plugs and starter motor to work, and you need a 9 volt battery for the cutoff solenoid). The electronically-controlled pump needs a wiring harness and ECU and several sensors, including that drive-by-wire accelerator pedal.
If you are building an older vehicle with a TDI engine, there's no question that you CAN make it run with a fully mechanical pump (no electronic control) and it's been done several times.
But if you go to the trouble of re-wiring the relevant portions of the vehicle, the electronic pump control will give a degree of control over the injection quantity and timing (and boost pressure) that cannot be achieved with the completely mechanical pump - if the tuning is right. This is why VW did it this way. Better driveability, lower emissions, less noise, better cold starting, better fuel consumption, etc., as long as the tuning is right - but that "right" level of tuning cannot be achieved to the same level with the fully mechanical pump.
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Yes the electronic control makes a big difference, yes it can change a few things with the throttle and timing on the fly based on external pump sensors. Does that make it better? No. Are emissions and noise your only argument for why they are a superior fuel pump? Yes.Yes ... BUT ...
The electronically-controlled pump is capable of regulating the injection timing and quantity (under electronic control). The mechanical cable-operated pump is only capable of manual timing control (the cold-start handle).
No, wrong. The TDI pump and IDI pump are exactly the same with regards to the throttle. They both have case pressure activated timing advance mechanisms, if they didn't then how did I take my 1998 AHU TDI pump and use its internals inside of a 1988 1.6 pump to make myself a mechanical DI pump? What changed between the 98 pump and the 88 pump? Only the throttle of the pump essentially.
The electronically controlled pump is capable of, for example, advancing the timing with RPM to account for ignition delay. A mechanical cable operated pump cannot do that. You are stuck with the timing that you mechanically set it up to - no automatic variation with speed and load - unless you feel like playing with the cold-start handle manually while driving ...
Well that whole paragraph proves to me the rest of your post is also just here-say and your opinion with no factual evidence to back it up.Oh boy. "no automatic variation with speed and load" Are you kidding? You really believe that injecting the fuel at 0.88-0.95mm before TDC at idle is what the timing stays at for the whole time during the pumps operation?? How could the fuel be injected at the same time (not accounting for ignition delay) and run well at all? The cold start handle is only for in-cabin advancing of the timing at idle and up to about 1100 pump RPM
The electronically-controlled pump is capable of delivering a different injection quantity with RPM at the same boost pressure to account for the engine's differing breathing capability at different revs - it's all in the mapping. The mechanical cable-operated pump cannot do that. It's capable of backing off the injection quantity when the intake air temperature goes up ... the mechanical cable-operated pump cannot do that.
All for efficiency and emissions. Not at all needed or mandatory for the proper operation of a diesel engine.
It's correct to say that the means by which the plunger is actuated and sends pulses of fuels out to the injectors is the same between the mechanical cable-operated pump and the electronically-controlled pump. They are internally very similar.
No. Internally they are exact, with regards to the throttle. Both are timing belt spun, that spins a pulley. That pulley spins the pumps main shaft. That main-shaft then spins the cam-plate, that cam-plate then rides the rollers in the roller cage. The lobes on the spinning cam-plate cause this now rotating assembly to reciprocate. Causing? you got it. Mechanical Injection.
Everything about this picture is to do with Injecting of the fuel. It is identical between IDI and the AHU/ALH TDI pumps.
![Image]()
But it is not correct to say "The fuel delivery, the amount of fuel delivered and the time at which it is delivered does not differ between M-TDI and E-TDI. Learn some stuff before you go spewing incorrect information."
My statement was 100% correct, actually.
The electronic control makes a big difference ... and it's why VW went to electronic control with the TDI and completely abandoned the mechanical cable-operated pumps. The electronically controlled system was capable of meeting emission standards (at the time) and delivering acceptable noise level and performance (at the time). The mechanical pump could not do that.
Have you had either apart? Just tell me, if you have.. well you need to take a bit better look next time you are inside of one. If you haven't well then... your entire post was speculation, and stuf you have read or seen from others' experience. Sorry sir, but without actual experience your knowledge is void.
THEF-inMAN53 said:
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Very hard to say my friend. As they never had a electronically controlled IDI engine in the VW line-up.. How can you say most of that new found awesome didn't come from the switch to DI in itself??
I have a 550,000km AHU M-TDI in my driveway right now. BESIDE a 400,000 AAZ. Both fully mechanical. I can start my M-TDI down to -15F with no glow plugs or frost heater. It is quieter, more efficient, starts perfect in the cold, and emits less smoke..
So where does your electrical banter come in to this again?? All of what they gained for the 1996 1Z being TDI was NOT from the electricals... it was from the switch from IDI to DI fuel injection.
Boschs' literature contradicts you. As RPM increases, more timing is added via case pressure. The VE used on Cummins does have an electrical advance primarily used for cold starts via the KSB. The HP and torque curve also suggest an increase in timing.
Also, you CAN vary the fuel injected at RPM, the throttle does that by positioning the fuel collar on the rotor in relation to the spill port in the rotor. The boost pin further regulates that by where the fulcrum on the throttle lever is placed in relation to the governor.
The VP37 controls timing advance via electric solenoid(KSB, RPMs on M-TDI), RPM and fuel quantity via a solenoid that controls the fuel collar (governor springs, flywheel, LDA/AFC), and the fuel shutdown solenoid. Beyond those 3 things, it is ALL mechanical.
VW did it for a more controlled emissions output while trying to retain or exceed previous power.
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yuuuuuuuuuuuuup
There are distinct advantages and distinct disadvantages to the eTDI install vs. mTDI. My understanding is that the eTDI does affect the timing on-the-fly by opening or closing the solenoid at the bottom of the pump. This limits pressure to the advance piston. There is a feedback loop to the computer regarding actual timing by comparing the #3 pintle lift sensor and the crank position sensor. The full eTDI also more closely limits boost pressure to what is optimally required for the demand for power. Those two additional electronic controls can make a very slight increase in efficiency (1%?) over a well-tuned mechanical pump. With the mechanical pump and mechanically controlled turbo (e.g. wastegate) you can set the max fuel curve very accurately but there will more often be situations where either excessive boost is produced for the demand for power resulting in excessive back pressure or situations where there is excessive fuel being injected resulting in wasted fuel and increased emissions. The mechanical pumps can be tuned very accurately and erring on the side of excessive boost will come darn close to the efficiency of an eTDI. The eTDI also has neat features like data logging and the OBD system that assists you in diagnosing the problems that occur when those electronic components fail that are unnecessary to the mTDI.
The mTDI has several distinct advantages over the eTDI. There are lots of hack jobs out there that give the breed a bad name. I have heard of so-called mTDI conversions where the installer just stuck a 1.6 non-turbo pump on. Prothe even sells so-called mTDI pumps. Ha ha.
From this point on in this post, I'm only going to discuss the advantages of a properly set up mTDI. The most notable advantage to an mTDI is that it is more reliable. All the mechanical components that can fail on an mTDI engine are present on the eTDIs and just as likely to fail on either engine. However, the eTDI has a whole slew of additional components not present on the mTDI that can and do fail. This adds another layer of complexity and a whole slew of added failure modes that are not present on the mTDI.
The mTDI is more easily tunable for performance increases. For the eTDI to take advantage of upgraded injectors, increased boost pressure, turbo swap, etc, you will be relegated to paying for tunes. The most that is required on a properly setup mTDI pump is an adjustment of the max-fuel screw and the idle screw.
The mTDI does not need electricity to operate. A dead battery or alternator will not leave you walking. Remove the stop solenoid plunger and give it a push start and you're off to the races.
The time required for an mTDI conversion is a small fraction of the time required for an eTDI conversion. I literally pulled the 1.6TD engine out an installed an mTDI in a weekend while taking my time and goofing off. The only significant work was remaking the exhaust system.
I own both eTDI and mTDI and both are fun vehicles. I would pay more for a properly built mTDI than an eTDI.
The mTDI has several distinct advantages over the eTDI. There are lots of hack jobs out there that give the breed a bad name. I have heard of so-called mTDI conversions where the installer just stuck a 1.6 non-turbo pump on. Prothe even sells so-called mTDI pumps. Ha ha.
From this point on in this post, I'm only going to discuss the advantages of a properly set up mTDI. The most notable advantage to an mTDI is that it is more reliable. All the mechanical components that can fail on an mTDI engine are present on the eTDIs and just as likely to fail on either engine. However, the eTDI has a whole slew of additional components not present on the mTDI that can and do fail. This adds another layer of complexity and a whole slew of added failure modes that are not present on the mTDI.
The mTDI is more easily tunable for performance increases. For the eTDI to take advantage of upgraded injectors, increased boost pressure, turbo swap, etc, you will be relegated to paying for tunes. The most that is required on a properly setup mTDI pump is an adjustment of the max-fuel screw and the idle screw.
The mTDI does not need electricity to operate. A dead battery or alternator will not leave you walking. Remove the stop solenoid plunger and give it a push start and you're off to the races.
The time required for an mTDI conversion is a small fraction of the time required for an eTDI conversion. I literally pulled the 1.6TD engine out an installed an mTDI in a weekend while taking my time and goofing off. The only significant work was remaking the exhaust system.
I own both eTDI and mTDI and both are fun vehicles. I would pay more for a properly built mTDI than an eTDI.
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i have a rocco diesel
hey there! I have an 84 rocco with an 83 rabbit 1.6 na motor. I'll sell it to you and then if you want to swap an engine it's pretty much plug and play
hey there! I have an 84 rocco with an 83 rabbit 1.6 na motor. I'll sell it to you and then if you want to swap an engine it's pretty much plug and play
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I have no clue what you are talking about. My e TDI is garbage even with .216 noz and the malone stage 2. My 1.6 would eat that thing up. So no. No racing with the daily that can't get out of its own way.
I thought I only posted on this to further 8v and those saying that the pump on an ALH is mechanical. I would have to reread, but I never meant to imply the E TDI was a fast runner.
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8v-of-FURY not furry, I'm not a friggan labra-doodle for christs sake. I AM EIGHT POUNDING VALVES OF HELLFIRE. :laugh::laugh: :thumbup:
Seriously though, dafuq you on about? You are pro E and anti M?
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My bad FURY
and anyone whose e-tdi is "garbage" is DOING IT WRONG.
and anyone whose e-tdi is "garbage" is DOING IT WRONG.
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Either way.. same pump, same engine.. same power levels.
If you and your E-TDI do all the same mods as me and my M-TDI, we will make the same power and torque. I will be cheaper for lack of a tune needed, and return shipping for each subsequent "tuning".
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