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Engine Specific Info and Questions => IDI Engine => Topic started by: paolomarks on March 28, 2011, 03:58:18 pm

Title: what nozzles are you using on your aaz
Post by: paolomarks on March 28, 2011, 03:58:18 pm

I'm rebuilding the injectors from my 1996 AAZ.  It's got 200,000 miles and I think the original nozzles.  Havn't pop tested them but I think I'll replace them to be sure.  Nozzles in there now are 308's made in France. I'm not going for more than stock power from this engine, just want some fuel efficient, reliable nozzles.  What are you guys running and where are you getting them from?  Thanks, Paolo.

Title: Re: what nozzles are you using on your aaz
Post by: Thezorn on March 28, 2011, 09:46:27 pm

Why are you rebuilding them without pop testing them first, At 200km there is probabley a 99% chance they are still working as good as new. Your stock AAZ injectors should be 150bar.
The nozzels they come with are good for upwards of 200HP (or so Ive been told)

Title: Re: what nozzles are you using on your aaz
Post by: nathan_b on March 28, 2011, 10:17:03 pm

aren't they more complicated to pop test being dual stage?

Title: Re: what nozzles are you using on your aaz
Post by: Mark(The Miser)UK on March 29, 2011, 03:12:37 am

Quote from: nathan_b on March 28, 2011, 10:17:03 pm

aren't they more complicated to pop test being dual stage?

As far as I can tell, just pop test them exactly as other injectors.
All the twin spring does, is to enable the presquirt timing to be advanced compared to the main injection.This is done by reducing break pressure Most nozzles give a presquirt anyway, which may be seen when stroking injector tester slowly.
 Pre squirt is naturally, always in advance of main, but too far, and maybe it wont combust correctly. Might  be useful if engine spends much time at higher revs, as the initial burn rate is [almost] independant of rpm , and effectively increases the 'dwell angle'... perhaps not the best analogy. groups of nozzle numbers are matched to engine type/design, ie down to prechamber/ swirl chamber differences.

Didn't some AAZ injectors revert back to single spring? Or did I dream that :o

I don't run them, but did buy a genuine French set to look at, and stuff under the injector tester.
Only not using them because of the injector height mismatch, but nozzles look perfectly compatable with single spring. Somewhere I posted a picture of 293's and 308's [the needles] but no-one was brave enough to guess which was which ;D

Title: Re: what nozzles are you using on your aaz
Post by: paolomarks on March 30, 2011, 12:00:54 pm

hello,  I don't have access to a pressure tester. 200,000 miles on them not kilometers.