1."shave timing piston down"- Turn down the diameter?
2."Use the larger Drive unit from the ALH"- Does this get you more fuel pressure?
3. "Machining to accomodate larger shaft"- Drive shaft? sounds like I can do this with a reamer in my mill.
4. "Calibration" of pump- Injection timing or injection breakover pressure?
5. "Nozzles"- any suggestions on which nozles might be appropriate and safe for an older IDI pump? Rough estimate of pricing?
Any suggestion for models and prices of an aftermarket divorced fuel pump back at the "gas" tank?
1. No, diameter is not turned down...the top of the piston is shaved to increase travel and hence increase timing advance... Tin Tin will tell you...mTDI's like advance...
You can also swap the TDI pumps timing piston and internals as well...
2. the larger diameter mainshaft of the pumps is a "safety" measure. there is a debate out on it...many have run mTDI's and big IDI pumps without issue using the 17mm (smaller shaft...your IDI pump), others have not and have had the smaller unit snap. The larger 20mm shaft is a safety measure for increased torque on the mainshaft as well as the injection pressures that are higher in the DI engine. Not required...but a nice safety measure...and my philo is to do it once...do it right...so...
It does not increase injection pressures...
3. Sounds good..
4. Pumps are calibrated on pump test machines by bosch...the other method of testing is just setting it up on your car... injection pump timing is part of it...the indexing of the throttle shaft (you keep this in the same place when removed) is part of it, making sure internal components are torqued to spec and shimmed correct (i.e. plunger), etc.
5. Umm...safe, well...if the pump is built right you can run what you want. You need the pump to produce the fuel you need as per what your looking to get from your motor...then consider nozzles...
Which nozzle size depends on where you are going with your motor, etc. Also...quality is to be considered. There are nozzles out there for about $100-150 if you want them... then there are nozzles out there for 220-385.00. Quality does make a difference and in this case...size does too. If it isn't...you can still run what you want. Stock TDI injectors from the 1z/AHU motors are set at 190bar.... ALH units...220bar.
Check out ebay and
www.tdiracing.com for the lower cost nozzles and
www.kermatdi.com for the more expensive units and read/research about what each particular brand has (or may not have) to offer. Nozzle design is very important... there are many testimonials here, as well as over on
www.tdiclub.com as to experiences with different brands and such.
There are alot of considerations here. I'd suggest maybe digging a bit more into the operation of the pump, etc. and how/where you want to go with things for a better understanding. Naming "what something costs" can get pricey... and you could be dissappointed in the end (in that you may end up with overshooting how much you thought it'd cost..)
In all...expect to pay 150-385.00 for nozzles...depending on the quality, etc...
100.00 if you need to reshim your injectors, or 60-100 to have pop testing and shimming done (large injectors need to be reshimmed)
the pump...expect to pay anywhere from 400.00-1300 to get something setup up. Depends on what you have to start with, where your going, who is doing it and what you want to do... core pumps add up, used pumps, etc. etc. The list goes on and on...
There are a couple really good builders on here offering services...Tin-Tin is recommended, Giles is there... there are DIY'ers too.. and there are DIY'ers that use these guys services too...
Trust me..I've been there as have many others.
Joe