Hello,

Has anybody noticed the difference in lower seal dimensions compared to OEM? I searched but didn't see anything, my set of ID injectors has the Mazda wire plug soldered/potted on, they are direct plug and play. I measure ID's lower seals at 3mm height, OEM are 5mm. This is using a mm ruler and my aging eyes so they might not be exact measurements.

The ID seal is a little loose on the injector while OEM are a tight fit. My only guess is that extra 2mm is needed due to the combined injector and rail adaptor lengths. Has anybody used OEM seals with them? I won't be installing these for another two months due to the long MN winter storage plus I want to first install the fuel pump relay kit, then replace the OEM fuel pump. KISS, one thing at a time. I am also considering updating MS3Pro firmware from 1.5.2 (?) to 1.6.2 when I install the injectors, I used their spreadsheet to calculate dead and Small PW times based on 70 psi (NB2 non-return setup) as recommended by ID.

If the OEM seals fit I'll use them from a new seal kit that I purchased. A little extra pressure between the injector and manifold might help when running 18 psi, right?

 

NB fuel pressure is 60psi or 4 bar (58psi).

 

Following as I'll be doing the same thing in the next month or so. and converting to sequential in an NA chassis. Which vendor did you get the injectors from? I'd like to get ones that don't need adapters or connectors changed as well.

 

Let me look for the post that explains why they recommend 70 psi instead of 60 for the fuel calculations. I think it was basically that the rail is constant 60 psi BUT, under vacuum while idling where small pulse widths seem to be most important, the injectors are running as if the rail was at 70 psi pressure. 60 psi rail pressure and engine vacuum helping to pull fuel out as if the rail was at 70 psi.

Similarly, under boost with an OEM return-less setup, your 60 psi fuel pressure is effectively lower, subtracting boost pressure pushing against the injectors. The remote tuner I hired to get me past the worst of the learning curve and mostly tuned, he recently said 18 psi is around where an NB should really be adding an FPR or AFPR and return line. I'm running 18 psi and might install a better turbo than the GT2560R in 2027 as well as a 3" exhaust upgrade. 60 psi - 18 psi leave the injectors working as if fuel pressure was only 42 psi. With larger injectors and an aftermarket ECU I'll be fine without a return line BUT even with a better fuel pump pressure might still be dropping off near redline, high boost doesn't help that issue so the fuel table might still ramp up much higher than if it had a proper, manifold referenced FPR to help compensate and hold fuel pressure close to constant 43.5 psi (vacuum/boost compensated for by the 1:1 ratio?). I'm still in the early stages of looking into adding a return line.

Peter10, the injectors came from Goodwin Racing. Great service although the FedEx shipping (with signature) can be problematic. I find they are the worst but I'm a little biased as I've worked for USPS as a Letter Carrier for 20+ years. In my experience having deliveries to my home, FedEx has been a HUGE headache. Just today, I let a FedEx delivery guy into an apartment building I deliver and if I hadn't asked him not to, he would have propped a larger package up against the USPS mailboxes blocking it from being opened. I wanted to ask him to pull his head out but I was nice and just showed him the best spot he had just walked past, one that doesn't block me or customers from accessing the cluster box mailboxes. Internally I was screaming IDIOT as this is the second time this has happened in the last 7-10 days...I'm definitely not saying USPS hires the best and brightest either, especially recently!

 

Found it...Does anyone have ID1050x injector calibration settings? - Miata Turbo Forum - Boost cars, acquire cats.