Is it me or is it weird that your old OEM’s were almost perfect? And that the only significant delta saw a reduction in flow? Or am i misinterpreting this
Blake and I took ours to the same place to get cleaned and tested, and all of our original OEM injectors do appear to flow a little more than the Hitachi’s at 100% duty cycle. But we are curious if they reduced flow in new ones for a reason, as in, maybe these are a revised part.
I think the fact that the hitachi injectors or any injectors that are not oem replacements dont get built to the same flow output. It would make sense. When Audi or any manufacture has a part made for them even tho the part might share the same body they dont always share the same exact specs and that can effect flow and other aspecs
I just sent in a new OEM and hitachi as well as a used OEM for flow testing. Hopefully I’ll get them back by the weekend.
So cylinder #8 was the one I was curious about. It was stuck open and pissing fuel all over the cylinder. The reduction I’m guessing is the injector becoming un-stuck.
[quote=“65vetteC6,post:84,topic:7982”]
Excellent!
http://uploads.tapatalk-cdn.com/20160327/5218a066a3f7e872f16a80bece125745.jpg
Here are the two new ones I sent off, I’m guessing number 1 is OEM, 2 is hitachi based off of the other 8 OEM I sent in.
Here are my OEM that were cleaned.
http://uploads.tapatalk-cdn.com/20160327/4717410f8c78d5bd33063b10de37d274.jpg
Great info. How much does that flow rate difference between the 2 new ones (17 vs 18) actually affect things?
Thanks for doing that vette! So it’s confirmed there is a small difference of ~5-6% in peak flow rates between the OE and Hitachi injectors. Can you ask him if he noticed any difference in the spray pattern?
Can we equate that 5% flow difference to a 5% difference in engine power output?
Do we know of anyone running a full set of 8 Hitachi injectors? Some short term fuel trim logs at high RPM/WOT could tell us if the ECU needs more fuel than what the Hitachis can provide.
The ECU will adapt to the available fuel so I don’t expect any critically adverse effects to occur from the slightly lower flowing Hitachi injectors.
What numbers are you getting that 5-6% difference from?
Going off of the second sheet showing the before/after flow rates of the set of 8 OE injectors. It shows 17cc to 18cc is a +5.88%. It’s -5.55% for 18cc to 17cc.
Ah ok. Yea I’m curious to see a bigger sample size showing what brand new OEM ones would flow compared to factory-installed OEM’s, and also compared to the non-Audi branded Hitachi’s like the ones Blake and I have bought.
$5 says the non-Audi branded Hitachi’s flow exactly the same as the new Audi branded versions and these new injectors are a revised part, much like the high pressure fuel pumps that I replaced a few months ago which were a few revisions newer than my original OEM’s.
I think we have this data as of now. Vette had 8x original OEs, 1x new OE, and 1x new Hitachi flow tested. Maybe I’m misunderstanding you. Larger data set would still be useful.
I was poking an Audi parts rep about part revisions on the RS4 injector and as far as he could tell 079906036D is the only part number ever used. Usually they will do 079906036D,E,F for revisions right?
Yea that’s what I did I have another 3 of each if someone wants to pay for me to send them off hah I just didn’t feel like spending the money on injectors I’m planning to list for sale.
I spoke to chad at race city and he say the spray was the same.
The new OE ones (Hitachi’s) look very different at the inlet port, I’m surprised that there isn’t a different part number for them.
In any case, we need to see more brand new OE injector flow rates compared to stock to see if there is a difference, and compare that to the non-Audi branded Hitachi’s.
I have 4 brand new OEM injectors I’m sending off with my original 8 from the car, I’m having them all tested and cleaned and will pick the best 8, I’ll update here with how the brand new faired against the old units.
FYI scan the golf mkv/mkvi forums I found 4 brand new OEM injectors, and installation hardware, for 270 shipped to my door in Canada.
I just ordered 12x new Hitachi injectors from FCP since I couldn’t pass up the sale. They’re going straight to Race City Injector for flow matching a set of 8 and I will sell the remaining 4.
Edit: welp, those injectors are on backorder at Hitachi USA until late April.
Hi OzcarMeyer,
Are you using a local Vancouver shop to flow match your injectors or shipping them out somewhere else? Thanks bud!
Sorry for the late reply, I’m using BD diesel in Abbotsford, they have an asnu machine and are close to my house.
So what was the final word on the Hitachi injectors? I need to get 3 for my s6. (5.2L V10)
I’m looking at PN: 06E906036C which seems to be cross-referenced with Hitachi FIJ0033 on a few sites.
The Hitachis are a lot cheaper.
Should I hit or miss?