Mototron 60# Injectors

[Dabomb]

Is everyone out there than runs the Mototron 60#'ers did you also adjust the voltage as well as re-scaling IFR Table? Can someone post whats needed to make the Mototrons idle right. This thing smells like raw fuel at idle

[FRCTony]

So far I have:

Changed the IFR table based on the spreadsheet.
Lowered default and min pulse width values to .7.

The car idles well in closed loop, but the 02 switching is noticably lazier than with the stock injectors. All other times the switching is tight (like stock).

I tried some offset numbers from various sources with poor results so I am sticking with stock offsets until I discover what exactly is needed to make them as close to stock as possible.

Other than a ever so slight surge on light load transitions, the car has execllent drivability.

[Dabomb]

I just found this information spec sheet on the Mototron 60# injectors:

Calibration Information:
Static Flow 10.8g/s @ 600KPa
Impedance 12 Ohms (High)
Gain= .110ms/mg
Offset= .055ms
Turn On Time= 1.14ms @ 14VDc
Turn Off Time= .85ms @ 600KPa

How is this information helpful on scaling the injectors and taking out some of the bite at idle???

[redhardsupra]

where did you get this info?

[Dabomb]

Well,
I save everything I get my hands on. It's from a PDF file on the injectors themselves. Does this help?

[12secSS]

where did you get this info?

Mototron is very good at disclosing their injector information, I have seen the same info on their website.

[superls1]

I couldn't find that document on Mototron's site, but found it on Racetronix's. What do these injectors flow at 58psi? ~70lbs/hr?

[Dabomb]

The difference is minimal however there is a difference. There are plenty of injector charts on the site, I'll try to load one for you

[EC_Tune]

That means min Injector PW should not be set less than 1.14 msec. One table out of the way...

[Runn WS7]

great info.

[Billiumss]

Interesting...

[WS6FirebirdTA00]

at least someone gives some kind of data for injectors lol

[NigelTufnel]

The difference is minimal however there is a difference. There are plenty of injector charts on the site, I'll try to load one for you

So if I understand this correctly, 10.8 g/sec equates to 85.714 lbs/hr, and 600KPa equates to 87.023 PSI. Then, for a fuel pressure of 58 PSI, the numbers will look like this.

[Dabomb]

EC_Tune That means min Injector PW should not be set less than 1.14 msec. One table out of the way...

I have been advised that the 60#'ers dump so much fuel at idle it makes it difficult to have a smooth idle at low rpm. I set my injector pulse width to 0.881, after being advised to two different prominent and experienced engine tuners. But based on this new information provided seems like I need to readjust the pulse width back up to 1.14 all the way across, including the the defaultpulse with table???

[Reucroft]

If you log injector milliseconds at DFCO (fuel trim cell 21) i.e. when the injector is closed - will this not give you the turn on time? I'm running stock injectors and the lowest I get is 0.45 ms. You can plot this across the RPM range depending on what you log.

I'm upgrading to Accel 36lbs and was told by Accel they use 0.8 ms at 13.5 volts, i.e. a flat line.

[EC_Tune]

Minimum PW is just that. The time it physically takes to move the pintel/disc off the seat to the fully open position without fuel involvement.

The offset table is *added* to the minimum pw table to adjust for differing pressures across the pintel/disc which changes the opening time.

The short pulse adder is used to linearize the flow characteristics of the injector (shorter pw's are less linear) so the PCM can calculate a linear final fuel flow value.

[Dabomb]

Alright everyone,

I have another question for you that is related to the whole fueling question. Dialing in VE table with reasonable results, however, when that darn second fuel pump kicks in at 5# of blower boost; the car goes way rich and bellows black smoke and boggs really, really, really, (you get the idea) BAD. So my question is this. What would happen if I scaled the table at the appropriate KPa row in a lets say 25-50% fuel reduction to accomodate the second pump? Would seeing a step in the VE curve be a bad thing as everyone says you need a smooth VE graph, but dont some of the new production cars dispell the smooth graph myth???

If I can successfully reduce the VE at the right kPa row, which, in itself is confusing? I assume I add the 105kPa plus another 5psi converted to kPa to determine the correct row??? Is this how it works, meaning jump straight to the max atmosphere @105kPa then add the 5psi for the blower activating the second pump

This is my math 105kPa+ 34.47kPa (for 5psi)=139.47kPa when the second pump comes on??

[EC_Tune]

You *really* need to address the KR issue you have. Some places it's pulling 12-14 degrees! You have WAY too much timing for a boosted motor.