Maxing out the injectors again

[turbobob924]

Hey guys

Look at my sig for my GN.

What predictions for max horsepower and max boost levels??

I just did a little testing run during lunch with the 5.6 TT chip @ 18lbs. Getting up to 90% duty cycle on the 60 lb injectors. Around 19 degrees of total timing and around 25% E85. The 93 gas here already has 10% E added.

I doubt I'm making that much power at 18lbs on my 4.2 V-6. In only have pocket ported stock heads.

What's really goofy is that I only changed out the chip and injectors, from 50's with TT SD chip to 60's with TT5.6 chip. I think the WB showed 11.2 at WOT.

I was hitting 90% DC with the 50's as well.

So I added 20% more in injector and still am at the same place?? I did not think I was that lean before?

Maybe i need to use up all the gas and just try 50% Race gas and 50% 93?

 

[87GN_70GS]

Check your fuel pressure at WOT. I suspect that with the 60's @ 90%, the fuel pressure has dropped or is not tracking, delivering the same amount of fuel as you had with the 50's.

 

[turbobob924]

Good point I thought I had checked it but maybe....

 

[austinibew145]

I thought I was running higher and higher duty cycles. I found out why, there is some gunk in injectors cloging them up.

 

[GNVYUS 1]

Well your sig says 80lbs injectors and you're talking about 60's?

Going from 50's to 60's is only a 20% increase and considering you have a 4.2L it's a tad easier to eat up the injector faster on E85, especially if you're mixing E85 with it.

Not sure how you're going to keep a tune with an odd mix of 25% E85 all the time. 93 (%10 in that) and E85 (%85 in that), this alone would drive me nuts tuning.

I'd only mix 50/50 as my lowest with E85 to keep the tune in place. Otherwise just mix in racegas and then run Alky and be done with it.