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Engine Specific Info and Questions => IDI Engine => Topic started by: zagarus on January 02, 2009, 08:45:03 pm

Title: IDI injectors
Post by: zagarus on January 02, 2009, 08:45:03 pm

I'm curious as to what the difference between 1.6TD injectors and 1.9TD injectors are.  Do they operate differently or is it alright for me to use my 1.6 injectors with GTD nozzles in my 1.9TD?

Title: IDI injectors
Post by: cyrus #1 on January 02, 2009, 09:04:43 pm

AAZ injectors are 2 stage where 1.6 injectors have only a single injection.  The idea was a quieter engine. Vincent Waldon has a nice write up on injectors here.  http://vincewaldon.com/index.php?option=com_content&task=view&id=20&Itemid=28  There is a picture of the 2 different styles near the bottom.

I'm not 100% sure but I think I remember reading that AAZ injectors are taller so your 1.6 injectors may require 1.6 lines.  I'm also not sure what the performance gain/loss would be.  :?

Title: IDI injectors
Post by: zagarus on January 02, 2009, 10:02:07 pm

thats the main reason i want to know what the difference is, if there is any preformance gain/loss. IF there isnt then i can use my already tested and properly configured 1.6 injectors with the lines to go with them. I dont need a quieter engine anyway :P

Title: IDI injectors
Post by: Smokey Eddy on January 03, 2009, 02:35:16 am

From what i've read (and my understanding) the difference isn't significant.

All it is two injections from the aaz ones vs. 1 injection spray from the 1.6 injectors.


The first spray is supposed to dampen the noise or some crap. They are very difficult to pressure test too without having the proper equipment. Another draw back to two stage injectors.

For what it's worth i'd say stick with the 1.6 injectors since you already have the set up for them and they are in working order.

BUT i would trust what ever Vincent says.

Title: IDI injectors
Post by: burn_your_money on January 03, 2009, 07:27:35 am

AAZ injectors are meant to quiet the engine down by gradually increasing the cylinder pressure. You are suppose to get better mileage with them(2 stage), although I'm not sure if anyone has tested AAZ injectors on a 1.6?

The length of the delivery valve holders are different on the 1.9/1.6 pumps plus the 1.9 injectors are taller, and the block is also taller. Basically, no matter what lines you use you are going to have to bend them to get them to fit.

You start with an initial pilot injection which gets the combustion process started and then the main injection occurs at the higher pressure. When we test these at work, I can't see 2 separate injections. I believe (but don't know for sure) that it is one continuous injection at two different opening pressures.

Title: IDI injectors
Post by: TurboJ on January 03, 2009, 08:00:35 am

Quote from: "burn_your_money"

AAZ injectors are meant to quiet the engine down by gradually increasing the cylinder pressure. You are suppose to get better mileage with them(2 stage), although I'm not sure if anyone has tested AAZ injectors on a 1.6?

I will soon, I'll report if there's a rise in MPG :)

Title: IDI injectors
Post by: zagarus on January 03, 2009, 09:04:41 am

alright good to know, maybe ill send my injectors to giles along with my pump, just to keep things simple...Whats a good nozzle for 1.9 injectors :P