Great FIC article on Injector Offset - Page 2 - ZR-1 Net Registry Forums

mike100 · 01-29-2015

Quote:

Originally Posted by XfireZ51

Mike,

Currently I run Accel 150121 injectors which I believe are Lucas injectors. However, I am using the offset values for the 24# injectors. They're rated at 43.5# FP so I am hoping that the values would be accurate. I'm in process of verifying that.

Can you forward me the values? I may try them out to see if it feels any different driving slow.

XfireZ51 · 01-29-2015

Here's a compare of the offset numbers I'm currently using v stock. Black line is current, red line is stock.

Mike,

If you have a stock bin, you should be able to determine the values by subtracting the numbers in the table. The graph demonstrates the difference in the offset over voltage. You can also go here for the 24# injectors. There are .pdfs available for other size injectors. If you use these values, you WILL need to modify VE tables.

http://data.prestoliteperformance.co...ons_150124.pdf

XfireZ51 · 03-12-2015

Recently I was able to get the ACCEL 150121 injector flow checked. These injectors are rated at 21# using a rating pressure of 39psi. It's reasonable to expect that the flow would increase w pressure but in the case of these injectors flow did not change w an increase in pressure. In fact, they flowed 20.6# whether using 39 or 43psi.
So using the Brake Specific Fuel Consumption formula, these 150121 would support

(20.6*16injectors*.8 Duty Cycle)/.5# per hp. = 527chp
At .85 DC they should be good for 560chp.

These are an older style injector but are made well and pretty reliable. Their control is linear until about 1.4ms pulse width.

The Accels are a popular replacement injector for the LT-5. Not expensive, reliable and w a similar spec as the Bosch injector. However, the offset diverges from stock. It's also likely not the injector of choice for any LT-5 beyond a cammed & ported 5.7L motor. IMO, bigger displacement should look for other injectors and we are seeing people recognize that the injectors are going static in larger, more powerful motors.

01-29-2015	#12
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,683	Re: Great FIC article on Injector Offset Here's a compare of the offset numbers I'm currently using v stock. Black line is current, red line is stock. Mike, If you have a stock bin, you should be able to determine the values by subtracting the numbers in the table. The graph demonstrates the difference in the offset over voltage. You can also go here for the 24# injectors. There are .pdfs available for other size injectors. If you use these values, you WILL need to modify VE tables. http://data.prestoliteperformance.co...ons_150124.pdf Last edited by XfireZ51; 03-08-2024 at 03:10 PM.

03-12-2015	#13
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,683	Re: Great FIC article on Injector Offset Recently I was able to get the ACCEL 150121 injector flow checked. These injectors are rated at 21# using a rating pressure of 39psi. It's reasonable to expect that the flow would increase w pressure but in the case of these injectors flow did not change w an increase in pressure. In fact, they flowed 20.6# whether using 39 or 43psi. So using the Brake Specific Fuel Consumption formula, these 150121 would support (20.616injectors.8 Duty Cycle)/.5# per hp. = 527chp At .85 DC they should be good for 560chp. These are an older style injector but are made well and pretty reliable. Their control is linear until about 1.4ms pulse width. The Accels are a popular replacement injector for the LT-5. Not expensive, reliable and w a similar spec as the Bosch injector. However, the offset diverges from stock. It's also likely not the injector of choice for any LT-5 beyond a cammed & ported 5.7L motor. IMO, bigger displacement should look for other injectors and we are seeing people recognize that the injectors are going static in larger, more powerful motors.