mTDI nozzles and breaking pressure - TDI Engine -General Info - VWDiesel.net The IDI, TDI, and mTDI source.

• mTDI nozzles and breaking pressure by monkey magic on 11 May, 2010 08:32
• Hi chaps, 
  
  slowly chipping away at my landrover pump based mTDI set up, and am now sick of the smoke on start up (injectors need servicing).  Also, talk on here of 11mm head working against stock 90BHP nozzles being bad for the pump makes me nervous.
  
  So, I'm getting my local injection man to fit me the nozzles, and I was wondering if I should get the breaking pressures set higher to match the 110BHP set up (220 bar I believe)? Or is there another pressure level that would properly match the landrover pump?
  
  Also, I assume changing this pressure would mean I should alter the pump timing a little more too?
  
  I am looking at sprint 520 or PP520 nozzles, my engine is AHU, stock turbo, running a standard landrover pump (0460 414 068) with 11mm head, and its pushing 2 tonne of van!
  
  I do have plans for different nozzles again in the future, to suit a giles pump and vnt turbo, but for now, Im just trying to make my van a little happier without breaking the bank.
  
  All opinions and info welcome..
  
  Cheers, MM
  
  
  
  
• #1 by rolo on 11 May, 2010 09:47
• You know how mine`s set up I`ll add it for anyone to see and my thoughts later. Just for now I`d like to know if you`ve  or anyone`s tried turning the pump up and any results. The reason for that is that my pump is set to max on all the usual ---boost pin orientation, start point and star wheel as well as max fuel screw.No black smoke. Whilst it goes well an no black is good, I`m surprised. Cheers rolo.
• #2 by monkey magic on 12 May, 2010 01:14
• Quote from: rolo on 11 May, 2010 09:47

  You know how mine`s set up I`ll add it for anyone to see and my thoughts later.

  
    Refresh my memory, I have a lot spinning round my head at the moment!  I know you have the gov mod done, did you say you've got bigger nozzles in there also?
  
  Havent tried tweaking mine yet, darent do anything with the pump until my EGT is in place. Also I still need a chargecooler in there (next 2 weeks hopefully)..
  
  I dont mind doing the gov mod, may have a go once the chargecooler's there. And also the star wheel, but dont want to get too involved in pump tweaking.
  
  I can remember being young and daft enough to ignore people telling me not to mess with the settings on my carburettors, and now appreciate these things (carbs & IP's) are too specialist for people like me to have great results and minimal problems! 
  
  Whats the best source for genuine bosio nozzles in the UK? Seems daft if I have to order an italian product from the US (bit like when I bought my German springs from the US  )!
• #3 by burn_your_money on 12 May, 2010 05:04
• Depending on how much fuel your LR pump is putting out you might be fine.
  
  The automatic uses smaller nozzles then the manual even though the auto has an 11mm head.
  
  Make sure that the guy at the shop can actually check both opening pressures. Higher flowing injectors typically drastically lower the secondary pressure even after correcting the first pressure with the pressure pin as per Bosch's methods of rebuilding TDI injectors.
  
  Bosch's pressure setting proceedure only works with stock nozzles. Bosch specifically designed their TDI injectors to be rebuildable using your standard pop tester. However as soon as you start swapping in higher flow nozzles everything goes out the window.
• #4 by svenakela on 12 May, 2010 07:01
• What pump do you have? I have a LR 300 (Discovery) pump and I haven't heard that there's a risk that the pump can break.
  
  There's an image here on my pump
• #5 by monkey magic on 12 May, 2010 09:35
• Hi Svenakela, mine is a 200, looks the same as yours.
  
  

  Quote from: burn_your_money on 12 May, 2010 05:04

  Higher flowing injectors typically drastically lower the secondary pressure even after correcting the first pressure with the pressure pin as per Bosch's methods of rebuilding TDI injectors...
  
  ... as soon as you start swapping in higher flow nozzles everything goes out the window.
  

  
  Thats good info, thanks. The guy can check both pressures, and did question me about how these should be set given the use of a different nozzles.
  
  Perhaps I should stick with using the standard bosch nozzle for a 110BHP and setting both pressures according to standard for that engine? Would that give me a decent result against the current set up?
  
  I have no idea where i would start figuring this out, and although my diesel man is good, he isnt into non standard stuff but is happy to have a go at whatever i guide him to doing!
  
  
• #6 by burn_your_money on 12 May, 2010 09:56
• I'm a fan of stock Bosch nozzles. The quality far surpasses any of the aftermarket stuff. You won't get as much power though so it depends on what your goals are.
• #7 by rolo on 12 May, 2010 11:10
• Bosch 215 nozzles set at 220 and balanced. Pump maxed out. vnt 15. Revs past 5. Was better with aaz cam but the higher inlet lift worried me when I did the govenor.  The nozzles alone put 5mph on top speed but thats the only thing I could measure. Will get some dyno figures soon. Oh yes, the timing is now at 1.5 wouldn`t run at 1. The best mod is the gov as it allows more fuel lower down the rev range and doesn`t really need revving much past 4. The power to weight ratio in the caddy, (970kg) makes it quite quick. Now going to build another for the van with the 17 on, but looking for an LT pump.
• #8 by monkey magic on 12 May, 2010 12:14
• Not wanting silly power, just thought if im overhauling the injectors may as well upgrade the nozzles a little.
  
  So rolo, when you say set to 220, how does that tie in with the 2 stage thing? And (if you have it handy  ) whats the full bosch part number on the 215's?
  
  
• #9 by snakemaster on 13 May, 2010 15:25
• i have run 11mm head with std 90hp injectors and a gt 15 for over 3 years and no prob and i tow 1500 kg behind the car quite a lot . one prob is if your hard on the throtle it will spin the wheels even in third and in the wet it is every gear ,
  try and get a hold of 110hp injectors . i run 190bar  , i was running .216 nozzles on my std 90 injectors more power but was geting clutch probs . so went back to std injectors 90hp
• #10 by rolo on 14 May, 2010 23:39
• Thought about the second stage before going ahead. Talked to the man. He operates in a rural community and comes across lots of discos and gets best results from an initial 220 on the std nozzles. I understand some of the theory but will listen to a pro. He set the injectors as he thought best. He built a 280bhp golf last year and is doing a 200 caddy pickup as a promotion. My bit of knowledge tells me they may be working basically as 1 stage but no noisier than the aaz. The performance was noticably improved. ------- For your purposes, mm, I`d go for the afn set up  The damage to pump message and timing at 1mm came from a french speaker on here. Does it really take 4 months to do a 1 off pressure plate?
• #11 by rolo on 15 May, 2010 12:02
• Just got an afn engine and turbo, right money, for fixing an aef for someone on brickyard. If you want to try the injectors let me know. Cheers rolo.
• #12 by monkey magic on 17 May, 2010 14:39
• Thanks for the input all everyone, going with the 110 injectors does seem like the sensible way to go.
  
  And on that note, Rolo,...
  
  yes deffo interested. Are they available for purchase? And is the turbo available too 
  
  Looking forward to doing the gov mod, I can see that and the injectors being significant upgrades..
  
  Glad you've worked your way up to 1.5 with the timing (similar to mine), saves me experimenting!