Introducing the new AUS injector design. We contacted AUS with an idea to improve the general design of the side feed injectors and the good people at AUS not only listened to us, they worked directly with us to improve the design and fix the inherent design flaw that ALL side feed injectors have.
All side feed injectors that are made to use in the Z32 can and do become susceptible to cap failures. What happens is that over time, the caps become brittle and can break off. This cap is important in holding the injectors lower O ring in place. While most of the work of holding the O ring in place is done by the fittmend of the O ring to the bore, it can and does work it's way down and relies on the cap to keep it in place. When the cap comes off, it will shoot down into the lower plenum where it will either get stuck or in extreme cases, it goes through the piston and valves etc.
When this happens, the O ring is left to fend for itself. In best case scenarios, it gets stuck at an angle and only partially comes out causing a real rich condition and a misfire in that cylinder. In more extreme cases, the O ring will come all the way out. When this happens, the entire fury of the fuel pump is allowed to flow fuel into the affected cylinder. This causes a massive hydrolock that usually leads to bent rods, damaged pistons or even chunks taken out of the head surfaces.
This design was flawed from the beginning because it relies 100% on a plastic/nylon part to keep the engine safe. While for the most part, this setup has worked well for the platform, there have been many failures over the years on injectors from every manufacturer out there! In my 25 years of owning and working on these cars, I have seen it over and over again. Yes even the coveted Nismo/Tomei injectors fall victim to this issue.
As time goes on, more and more things are being made in China. For the most part these caps are now made there and have suffered in the quality control department. So with this in mind, I set out to improve upon this part and remove the issue all together.
I have a very close working relationship with the owner of AUS injection and decided to reach out to him on this. After having reached out to other manufacturers about this, they either did not answer my messages, or they flat out declined to make any changes due to the dying use of this injector in the automotive world. Top feed has become king in the OEM and performance industries.
When I reached out to AUS injection, they assured me that they wanted to help make improvements to their performance line of injectors. They valued my input on this and we worked together to create a better solution to the problem. They are the only injector company that was willing to not only listen to me, but wanted to work with me to make their product the best it can be. In my opinion, this is paramount to moving this platform forward. With the onset of E85, there has been a huge influx of N/A Z32 owners that want to convert to E85 and run OEM turbos or larger on their cars. For these people, running a top feed fuel injector system simply does not make sense. The cost alone for that can often become more than 1/2 the cost of the entire swap. This can make or break them taking the plunge into the boosted life!
Having a larger side feed injector than 740cc is important to making more than 600hp with E85. For many people It becomes an obstacle to go any higher due to top feed conversion costs. This keeps them from going for more power than a 740cc injector can support. Having a company like AUS that is willing to work with us to develop and supply our platform with a good product that works is very exciting! It helps to bridge a gap for growing number of Z enthusiasts.
After I presented my input on design improvements for the injector caps, they went to work and sent me a set of injectors with a crude modification as proof of concept and a prototype for us to test. I gave them my feedback and the set out to make a cad drawing of the final product. I had them make a couple of changes to the final design and they had it produced. They sent us a set to test out and it was a home run!
After it was all said and done, AUS has confirmed that not only will ALL of their larger performance injectors come with this new cap, they will also be included on all OEM size injectors sold by ZShack!
Here are some photos of the prototype proof of concept injectors as well as the cad drawing and final product. From here on out, all AUS injectors sold by ZShack will include this new and improved cap design. This cap has been tested against heat variations and pressure to ensure that the caps will not come off.
The design is machined to snap on to the injector tip where the plastic cap snaps on as well as being punched on around the sides to make the caps permanent, while not distorting the nozzle shape or the spray pattern.
The caps are made from solid billet aluminum and are CNC machined. Making these caps much stronger than any other injector caps out there.
We are proud to introduce this new and improved design...........
Prototype proof of concept injectors
New cap design CAD drawing
Final product
We hope that this will put everyone at ease about these injectors and stop the naysayers that continue to hate on this company and lump them into the same category with Ebay type cheap Chinese knock off injectors. We have installed and tuned more Z32's with these than any other shop and have had really good luck with them. As with every product and company out there, they have had a few failures over time, but they always make it right with no haggle replacements and such. They are truly are a customer service driven company.
At ZShack, all we work on is the Z32 and nothing else!
We are committed to this platform and are constantly working to improve the platform, to make more power than ever before, and help share the knowledge with everyone.
FOR THOSE THAT WOULD LIKE TO HAVE THEIR USED SET OF INJECTORS UPGRADED TO THESE NEW STYLE CAPS, AUS NOW OFFERS AN OPTION TO SEND YOUR INJECTORS TO THEM FOR CLEANING, FLOW TESTING AND CAP REPLACEMENT. tHE COST FOR THIS IS $25 PER INJECTOR.
PLEASE CONTACT AUS INJECTORS DIRECTLY FOR THIS SERVICE.
ZSHACK DOES NOT PROVIDE THIS DIRECTLY