New FIC 1700CC Injectors - No Start

[nitrousgp]

Installed new Fuel Injector Connection 1700cc injectors and used the injector they gave me. Set my regulator to 58psig, but I'm not getting the car to start. I'm guessing it's because I have something wrong in my injector tables, but it seems like the injectors are firing at all. No fuel smell, but I definitely have 58psig pressure at the rails. I've attached the injector data that was given to me and the current tune. Could someone take a look and see what I have wrong? Car is an '09 C6Z with a Fore Innovations triple pump setup and manifold referenced regulator set at 58psig currently. Thank you!

Raised Startup Idle with 1700cc Injectors.hpt
1700cc(6667)boschev14_03242022.xlsx

[5FDP]

You didn't scale the rest of the stuff for the large injectors.

I'd honestly lower your fuel pressure to 43.5 and then use the double stoich method.

Double the stoich, half the injector flow rate and half the IVT terms afr term table.

Kinda sucks your computer only allows for 127lb/hr injectors on the double stoich method. And not sure why you picked such huge injectors, unless to plan to make like 1300+ horsepower.

[nitrousgp]

You didn't scale the rest of the stuff for the large injectors.

I'd honestly lower your fuel pressure to 43.5 and then use the double stoich method.

Double the stoich, half the injector flow rate and half the IVT terms afr term table.

Kinda sucks your computer only allows for 127lb/hr injectors on the double stoich method. And not sure why you picked such huge injectors, unless to plan to make like 1300+ horsepower.

I was planning to do the double stoich method, but my ECM only will allow 127lb/hr. Half the flow rate would be about 86lb/hr. I was looking at doing the 2010+ ECM upgrade to be able to do that. What other tables need to be scaled for the injectors?

It's a twin S475 car. Hoping to crack 1500HP.

[07GTS]

only the tables mentioned do the scaling, the other injector tables (offsets) need to be setup to suit the referenced reg and at what pressure u are running base pressure, if u were on e85 only u can do the triple stoich and divide by 3 for the IFR and IVT terms, wont work if ur flex or petrol tho

[nitrousgp]

only the tables mentioned do the scaling, the other injector tables (offsets) need to be setup to suit the referenced reg and at what pressure u are running base pressure, if u were on e85 only u can do the triple stoich and divide by 3 for the IFR and IVT terms, wont work if ur flex or petrol tho

Yes, I plan to switch back and forth from 93/E85.

I have my flow rate vs. press all set to 58lb/hr. That's what I have my regulator set at. I also have my Offset vs. Press vs. IGNV with each column set to the 58psig data.

It seems as if the injectors aren't firing at all. Pulling a plug shows no signs of fuel.

[07GTS]

to fit those injectors in u may have to scale it by 3 using 2/3 by fuel stoich and 1/3 by airflow, this will take alot of work as u have to scale every table that uses airmass, it also throws torque model out so u have to set that back to be right again too PITA but if this was if done right (mathematically) should still allow u to use flex sensor, in your file u posted u still have to double the stoich and halve the ivt terms

[blindsquirrel]

For some combos the stock ECM just is not the right/best choice.

[Turbo6TA]

I am surprised that you can even get 1700cc injectors to idle at 58 PSI fuel pressure in an LS engine while using the stock ECM.

I say that because in my supercharged LS3 (running on 93 octane pump gas), my 72 Lb/Hr (755cc) operate at between 1%-2% duty cycle while idling.

I would think that 1700cc would need to operate at maybe 0.5% duty cycle while attempting to maintain a 14.7 idle AFR.

Just don't seem possible that the 1700cc injectors could operate correctly at that low of an operating duty cycle.

Maybe I'm wrong ?

[nitrousgp]

It can be done. My brother has an F1A-94 car with 1650s on the stock ECU

[07GTS]

i was using 210lb injectors for a while on ethanol idling with 0.5ms PW at stoich stock ecu, my build now will have 1500cc running bout 40psi base pressure just so i can still use petrol without too much worry if i had to

[nitrousgp]

i was using 210lb injectors for a while on ethanol idling with 0.5ms PW at stoich stock ecu, my build now will have 1500cc running bout 40psi base pressure just so i can still use petrol without too much worry if i had to

It sounds like if I lower my base pressure (to around 43.5psig) I may have better luck?

[blindsquirrel]

The Stoich table allows a max of 32, which gives you a factor of 2.17something, and at 40psi your injectors flow ~18.35g/s. Dividing 18.35 by 2.17 still puts you over the early ECM's max limit of 8.00g/s by a fair amount.

It's doable without airflow scaling (injector scaling only, this is OK) if you can switch to a late 127lb ECM. Keeping the early 63lb ECM means either injector scaling plus airflow scaling which, to me, is a bridge too far, or, smaller injectors/lowering your goals somewhat. The early ECM just is not the right tool for this job.

[nitrousgp]

The Stoich table allows a max of 32, which gives you a factor of 2.17something, and at 40psi your injectors flow ~18.35g/s. Dividing 18.35 by 2.17 still puts you over the early ECM's max limit of 8.00g/s by a fair amount.

It's doable without airflow scaling (injector scaling only, this is OK) if you can switch to a late 127lb ECM. Keeping the early 63lb ECM means either injector scaling plus airflow scaling which, to me, is a bridge too far, or, smaller injectors/lowering your goals somewhat. The early ECM just is not the right tool for this job.

Thanks. I am likely going to upgrade to the 2010+ E38 ECM to avoid having to scale airmass tables, if I can help it. That would give me some room in the flow rate tables to do the double stoich method.

[blindsquirrel]

Before you jump you should look into what all other changes you will have to make, if it's even possible. This is in the 2009 Corvette? It's an early 2009? The change from 63 (12612384) to 127 (12625455) happened mid-year. So there are 2009 Corvettes out there with the late E38. However... the OSes are different, and you can't put an early VIN into the late ECM/OS, so you will have to also reflash, probably, every module in the car using a late '09 VIN. There were comms protocol changes (behind the scenes stuff) when the ECMs changed and the ABS/SIR/IPC/etc. need calibrations that are compatible with the new, different OS. I don't know if any of the other modules had hardware changes or not, but it's something you will have to research. It's not a plug-and-play kind of swap, even though they are both E38s.

You sure it wouldn't be easier to just leave the original ECM and all the other modules as-is and just add a piggyback ECU?

[blindsquirrel]

Ah, I missed that yours is a LS7... maybe all those were 63lb the whole production year. The '09 LS3 Vettes had the 127lb, again maybe for the entire year.

[nitrousgp]

Ah, I missed that yours is a LS7... maybe all those were 63lb the whole production year. The '09 LS3 Vettes had the 127lb, again maybe for the entire year.

I?m not positive, but I believe DSX Tuning sells the upgrade as a direct drop in/ PnP 2010+ ECM. I?ll need to confirm. I also have access to a Tech 2, but I?d rather have someone do it right the first time rather than mess around with it on my spare time (hah).