hey guys i m looking to updrade the injetors in my aaz the ones that are in it are 130 bar i have 1 set out of a 1.6gtd which say 160 bar would these be a worthwhile swap?
I've often wondered about this too. I was contemplating going to the Mercedes 155 bar nozzles when I rebuild my injectors. Is it worth it in a 1.6n/a? Any gurus have some insight?
I've often wondered about this too. I was contemplating going to the Mercedes 155 bar nozzles when I rebuild my injectors. Is it worth it in a 1.6n/a? Any gurus have some insight?
Many do not like the mercedes nozzles, something about the spray pattern and melted/cut bits.
On a 1.6 n/a the injectors are not the limiting factor until you've done a massive amount of work, how big is your exhaust? What header are you running? Do you already have a giles or similarly modded pump? I can't speak to the aaz injectors as I am unfamiliar with them entirely.
My thoughts would be:
- AAZ and 1.6 injector bodies are a different height... so you can't easily swap 'em... and since the AAZ and 1.6 delivery valves are usually different on the pump as well... rounding up hi pressure lines for a Frankenstein is a bit tricky. IMO not worth the effort because...
- the nozzle is almost never the limiting factor for power. In good condition a stock AAZ *or* 1.6 nozzle can likely flow more fuel than your engine can ever safely use
- for clarity... in case there's some confusion: the breaking pressure (130 bar, 160 bar) is not related to how much power you can get out of the nozzle... merely what pressure the nozzle has been calibrated to fire at within the injector body. 1.6 N/A injectors are generally set to 130 bar, 1.6 turbo to 155, and AAZ to 150... I've never actually seen a stock 160 bar injector but that means nothing.

If you do play with the breaking pressure... for what ever reason... you'll need to change the timing as well: the two are directly related. In general turbo injectors simply need a higher breaking pressure to ensure good atomization at the increased combustion chamber pressures under boost... not really a performance thing.
Bottom line... your AAZ injectors, if in good shape and properly calibrated, are probably serving you fine for whatever HP goals you have.
On the other hand, for folks running TDI engines upgraded nozzles *are* a very worthwhile upgrade... and sometimes thats where IDI people sometimes get confused as well... lots of "nozzle upgrades" on the interwebs.... for TDI engines only.
I used Mercedes nozzles and noticed no difference. I have to agree with Vince.
So would I be better of running TDI injectors in my engine?
cheers for the imput guys