building an M-TDI pump

[oldskool rich]

i cud do with a hand, dont understand what sum things are and i dont know what i need and dont need, if sumone whos built one can point me in the right direction that wud be great.

Jimfoo has already helped me alot, i understand you need the cam plate and springs off a tdi and obviously the bigger the pump piston the better.
then i get a bit confused after that

this on my aaz pump, what is it? do i need it?


this is on my tdi pump, what is it? do i need it? if i dont have it will it mess up the ecu?


this sping sum how advances the timing on the tdi, how exactly does this work? im guessing i need this on the M-TDI pump?


is there anything else i need to do?

also can you buy 12mm pump piston/ head? if so how much and where from?

[oldskool rich]

also made sum engine progress, PD pistons are in, just waiting for the pd crank to be machined to fit a 1Z pully, new barings all round and ive got one very strong bottom end

[jimfoo]

i cud do with a hand, dont understand what sum things are and i dont know what i need and dont need, if sumone whos built one can point me in the right direction that wud be great.

Jimfoo has already helped me alot, i understand you need the cam plate and springs off a tdi and obviously the bigger the pump piston the better.
then i get a bit confused after that

this on my aaz pump, what is it? do i need it?

Leave it hooked to power when running.
this is on my tdi pump, what is it? do i need it? if i dont have it will it mess up the ecu?

Put the parts in the AAZ pump to make an M-TDI pump. So that way you won't need to worry about that part.
this sping sum how advances the timing on the tdi, how exactly does this work? im guessing i need this on the M-TDI pump?


is there anything else i need to do?

also can you buy 12mm pump piston/ head? if so how much and where from?

[oldskool rich]

the white bosch plugy thing wont fit in the aaz pump, there is simply no where for it to go, i want to know if i need it, what it does and if the ecu can live without it, the other metal switchy thing on a pipe, just curious what it actualy does, its not connected to power on my aaz, and just wonderd why it exists?

[ThomZe]

My big question, why care about ECU on mtdi? isn't the point of MTDi, that here is no ecu?

[oldskool rich]

im a little confused, so there is no need for any ecu what so ever,

what does the ecu normaly control?

what about knock sensor, lambda sensor ect

i wanted to run everyting standard apart from the cable throttle and have an LDA, isnt it possible to still have an ecu, or is the tdi pump like the heart of it all?

sorry if i sound a bit dum, im new to all this tdi stuff, i always thort that there was loads of electrics involved, didnt know exactly what was ment by m-tdi

[RabbitGTDguy]

no...you do not need an ECU for a mTDI motor...hence "m" in TDI standing for "mechanical" ...so a non-ECU/ECM controlled, non-electronic pump. You could retain items from the AAZ pump such as electronic cold start (or from another pump)...but nothing ECU wise is need.  The only real connection you need is for the fuel stop solenoid (switch 12v) on the pump head...


Joe

[ezekiel]

Normally the TDI has all sorts of electronics because it runs an electronic pump, thus needing the MAF and the lambda sensor etc.

There's really no major differences between an IDI and a TDI engine except how they inject.  They both us the same basic idea when pumping fuel, the electronics with the TDI tend to make it run "better", but we all know wiring's a ***.

so you're basically taking the IDI parts, slapping them on the TDI, so you don't have to have ANY electronics except for what an IDI would normally run.

all of the timing done inside the pump on an IDI is mechanical, all the timing done inside a TDI is electronic.  Thus why it's an mTDI.

so you need your mechanical pump, with some parts from the TDI pump because of the way the TDI needs its fuel injected.  Which is where your camplate, springs, and pump-head come in.  TDI likes its fuel fast, so the camplate has an aggressive ramp-up to get it into the engine quickly.

[RabbitGTDguy]

Actually...its not as easy as just "slapping" IDI parts into a IDI pump to have a good setup.

The following needs to be considered and/or modified...

-IDI advance timing mech is "not enough" for a mTDI setup. mTDI's like their timing advance and the timing advance needs to be modified accordingly. The TDI mech is an improvement....but still is not enough. There are several threads on here about timing advance as well as different methods for changing "total" advance.

-IDI gov. control lever DOES NOT have enough travel for use in a DI mechanical pump. The internal housing of the pump as well as the lever needs to be modified to allow for more total travel if you want to pull max power out of your pump. Otherwise, it'll always be lukewarm at 50% of its possible power when turned up.

-There are also a few other governor considerations and modifications to take into account as well...however, starting with the AAZ pump you'll have a few less obstacles in one way...but then the worry about pump shaft size when it comes to high power, etc. Though...comments on busted pump shafts are still far and few in between what what I have seen.

You can slap IDI parts into the pump and make it work on a DI motor...but, it'll never run completely correct, have the correct timing advance, etc. without some more work. Also, it will never put out its full potential efficiently with a 12mm head. You (as has been said) loose a bit of efficient in leaving the electronics in the first place when going mTDI. An essentially IDI pump with a few DI parts will net you even more loss in efficiency and power unless the above is considered.

12mm heads are readily available from several pump applications out there. Namely, Cummins pumps from the 4bt seems to be a popular source. Beware of new heads on the market...some are 12mm heads that you can get "new" for a really cheap price but take a look at how poruous the metal is on them, there camplates, plungers and you'll find they are chinese heads. There have been several failures and "leaks" that have occured thanks to them. Even busted plungers and camplates! Get a good...used or if you can find them..."new" Bosch head

Joe

[snakemaster]

building a mtdi pump is a bastard compared to a 1.6 1.9 td . i am no expert i have been building or trying for the last 2 years ,i have got them running ok but power wise only 60%  its a bit of a black art , but the guys above are the kings off the Mtdi pumps , i wished i just got a pump from them in the first place save a lot off greef  my $2 worth

[oldskool rich]

ok point taken, since im in a rush to complete this car i might stick with the electric pump, can these be tuned? if i add a 12mm pump piston will that help?

how much power will i see with a big vnt?

[RabbitGTDguy]

-clarify "big VNT" (I see your looking for a GT20? Is that for this car?)
-If you want to use electronics...thats cool, but the 12mm pump head upgrade won't do it alone. Def. not the "pump piston" alone. The pump piston and hydraulic head need to match and be considered one unit. Additionally, you need a camplate profile that will make use and be matched to the hydraulic head your running (and yet the same profile for the advance curve of the engine your using it on.
- You'll have to have the ECM tuned to acct for the increase in fueling and your injector nozzles will need to be much larger (as mentioned before .260 plus) to get the power your looking for (from another thread)
-Your tuning will depend on what ECM you have...the earlier...the harder to tune *and in some cases...can't be "re-chipped" if I remember correctly short of some soldering coming into play*.

Giving out power numbers is hard to do without having these items in place and exactly what your looking to run. *i.e. I have a 12mm pump, Race 520 nozzles  (.263+) bar'd to XXX, xyz turbo running x psi, etc. etc*

Joe

[oldskool rich]

ok so the ECM needs tuning that doesnt sound too hard, i can get a 12mm pump piston, i have a cam plate off an 11mm pump, thats as close as i can get, .260 nozzles and and a VNT 20

whats the best i can hope for?

[Tintin]

The easy part for a person who has good skill in mechanics is to make enough work from the lever to the control collar on the plunger, more the came plate is aggressive, more work that need.  (came plate lift have nothing to do with the fueling)

The hard part is to get the correct timing curve, what the engine request VS what the pump can allow, but there are no tool to monitor the timing you want, It's try and error test on the road.

Even if you put a 12mm head on a electronic pump, the pump need to be rework to give the requested timing, playing with harder regulator.

Here an example of 12mm head on E pump:

[oldskool rich]

ok so now i see why people say just take a cable operated tdi pump off a different car. this all sounds extreamly hard, now i see how giles can charge that much for a custom pump

will any pumps off other cars fit straight on? also can the camplate and pp be changed for vw ones?

i just wana make life easy for myself tbh :lol: