A tuning tale: BLMs say lean, plugs say rich

[Top Toy]

Yes, I'll be very interested in what you learn. It's apparent from the table that if the values don't match the actual bias of the injectors that it would really screw up a good tune!

Sent from my HTC U11 using ZR-1 Net Registry mobile app

[XfireZ51]

Originally Posted by Top Toy

Yes, I'll be very interested in what you learn. It's apparent from the table that if the values don't match the actual bias of the injectors that it would really screw up a good tune!

Sent from my HTC U11 using ZR-1 Net Registry mobile app

Dennis,

Since the Bias value is a curve representing bias values at various voltages, it represents a significant portion of the PW calc when PW is small. That occurs during situations such as idle, decel, and trailing throttle as examples. The Voltage Bias is meant to compensate for votage change that happen when u turn on headlights, fans kick on, A/C operation, turn signals. A motor that seems to run and idle fine, runs like crap when it gets hot. U can try to fudge the VE tables but that only represent an ideal situation and doesn’t address all conditions which is a requirement for driveability, emissions and economy. And the values can be all over the board when it comes to injectors and manufacturers. And the values change based on fuel pressure variations. So its not as easy as just “slapping” in a new set of injectors. If u do that and datalog, u’ll find the VE tables changing. In the case of a modded motor, particurlarly w cams, it is one of the contributing factors to better controlling idle. Other tuners that I have great respect for, won’t tune a motor without those values.

[tpepmeie]

That’s why I use the Bosch/ford Motorsport injectors. All the info is available. Injector dynamics likewise, but theirs are too big for our applications. Fuel injector clinic has some 35s which they provide specs for. Still probably too big for all but the biggest motors.


Sent from my iPhone using ZR-1 Net Registry

[XfireZ51]

Originally Posted by tpepmeie

That’s why I use the Bosch/ford Motorsport injectors. All the info is available. Injector dynamics likewise, but theirs are too big for our applications. Fuel injector clinic has some 35s which they provide specs for. Still probably too big for all but the biggest motors.


Sent from my iPhone using ZR-1 Net Registry

Todd,

I’ll let u guys know if I get them. I think we may have identified these injectors as the Delphi FJ 10024 which is spec’d for the 89-91 L98. Should know more by Monday when they arrive from FIC. Hans says they’re rated at 22# at 43.5psi.
Accel was never forthcoming w their info on the 150121. I had someone test them to get the Bias values.

[Top Toy]

All makes perfect sense. Thanks for keeping is posted!

[Ccmano]

Originally Posted by XfireZ51

Todd,

I’ll let u guys know if I get them. I think we may have identified these injectors as the Delphi FJ 10024 which is spec’d for the 89-91 L98. Should know more by Monday when they arrive from FIC. Hans says they’re rated at 22# at 43.5psi.
Accel was never forthcoming w their info on the 150121. I had someone test them to get the Bias values.

Actually I think the ones your getting are Standard Products FJ47T’s likely made by Delphi (or the other way round). I haven’t been able to find a Delphi number but I do believe they carry a code 01D180B printed on the side. They may even be Lucas produced as Lucas injectors use a similar coding. I’ve seen them advertised as 22lbs but have not been able to find actual specs. Have you asked FIC what they are and what the specs are? I know they advertise them as Delphi.
H
: cheers:

[XfireZ51]

Hans,

Could be because the pic u posted looks like the one on the FIC website for the LT5 injectors compared to the L98 injector.
The first one is of the FIC LT5 injectors while the second is the L98. And I think u are correct that these are Lucas or Lucas style injectors.

[Ccmano]

This one was advertised as Dephi 22lb/hr injector. Note the code on the side.
01D180B....
H
: cheers:

[XfireZ51]

Injectiors arrived today from FIC. And they confirm what Hans speculated regarding which injector they are.
FIC shows them as flowing 21.5# at 43.5psi. The Accels I had tested flowed 21# at 3 bar. If this holds, I may need to tweak VE tables or I could try bumping Injector Constant a notch. Probably more significant than that is that the VE tables have been tuned to the Accel injectors I had which were deteriorating. And the car ran pretty well as it was. Marc Haibeck had a chance to drive my ZR from lunch one day, and he commented on how it ran well and accelerated smoothly. So now we’ll see what happens when u have all 16 injectors working.😉😂
One other difference between this and the Accel is that the aerator on the Delphis is recessed in the tip. As u can see from an earlier post, the Accel aerator is exposed at the end of the tip. I wonder if Delphi recesses the aerator to shield it.

[XfireZ51]

Here’s the difference in the aerator position between the Accels and the Delphis

The Delphi aerator is recessed quite a bit into the tip, while the Accel is exposed at the end. How that affects spray pattern I can’t speculate on.