[cjperformance]

Doing some estimation on inj pw based on stoich to see if I can guess where inj pw will end up at each eth % level.

Looks like I should be able to target E50-E60 and be at or around 5.5 inj pw.

E85 would def be out of the realm of possibility.

E35 sounds like a good starting point.

[cjperformance]

FF kit installed. Apparently "E85" is anything from E55 to E83 as the pump was labeled as such. With the tank at 3/4 full of 93 I put about 5.5 gal "E-whatever-it-is". Ended up at 27% eth, so it was probably something less than E85, but close. Might be a bit of a challenge to get the right mix if it varies from fill to fill, hopefully it is consistent.

So good news first, the sensor is working, no leaks. And the computer seems to be picking up the changes and changing spark and PE accordingly. I didn't feel any seat of the pants difference, which is actually a good thing considering a couple of items I noted below.

Couple things to work on.

#1 - Weird dip in low-side fuel pump (see image). This was not present with straight 93. Not really sure what to look at there. Maybe max desired pressure? I am still using the settings recommended earlier in this thread. Wasn't catastrophic, high side stayed high-ish and it came back up after the shift, but it happened about 50% of the time from a 30 mph punch at the top of the gear.

#2 - Commanded vs Actual AFR. With 93, the commanded vs actual was spot on. With the 27% eth it's pretty much a few % lean across the entire rpm range from idle to WOT. Wondering if I should tweak my stoich table instead of recalibrating the MAF? I would like to be able to fill up on 93 and still have things nice and accurate, so recalibrating the MAF would throw off the 93 tune. My stoich table was cross reffed with a couple of sources, but maybe it needs tweaking anyway? I added a screenshot of stoich table if anyone wants to take a look.

#3 - KR seems to be about the same as it was with 93... based on evidence, it's probably false and I need to desensitize my knock sensors.

Once I get the AFR, PE, and that fuel pump thing ironed out, curious to see where it puts my inj pw ms. Right now, there wasn't much change, with 93 on a 67 F day, it was about 4.5ms, and given the leaner afr and a 83 F day... inj pw stayed right at 4.5 ms on E27.

[laynlo15]

Low side is 31.3? Dangerous

[cjperformance]

Yeah had that issue before on 93, then fixed it by adjusting max desired pressure. Now its back with eth. Almost exact same thing. Must be flow related and ecu is dialing back in tank pump again.

[Joshinator99]

Originally Posted by laynlo15

Low side is 31.3? Dangerous

Agreed 100%

Originally Posted by cjperformance

Yeah had that issue before on 93, then fixed it by adjusting max desired pressure. Now its back with eth. Almost exact same thing. Must be flow related and ecu is dialing back in tank pump again.

What do your FSCM settings look like?

[cjperformance]

Originally Posted by Joshinator99

Agreed 100%



What do your FSCM settings look like?

Not sure what you want to see, but found a case in the log that was even worse. It's going strong, then it just falls off. Was going to try raising the max desired fp again, since that's what fixed it last time, but not sure what to do actually, or what's a safe setting.

Def wasn't happening with 93, but with the eth it is. I have 2 logs from today, one with 93 and one with eth, so it's a pretty clear correlation. As a reminder, I have the DSX aux low side kit. If it's not the stock pump backing off, then the aux pump is shutting off. Just with the fact it's ONLY since I started eth... it has to be something in the tune.

[cjperformance]

Here's average fuel pressures for two runs. Just an hour or so apart. Top one is 93, bottom one is eth. Looks like the average eth pressure is up across the board. Maybe eth is easier to pump and results in a higher pressure or something? This acts almost exactly like it did before I changed the max desired fp before.

I dont really know. The 93 log was a much longer ran the eth one, so not sure this comparison is meaningful or not.

[Joshinator99]

That’s not your FSCM…

Here's what I'm looking for:

[cjperformance]

Originally Posted by Joshinator99

That’s not your FSCM…

Here's what I'm looking for:

Its there. The very bottom image. Below the log screenshot. Here it is again though. 81.6 psi = 563 KPA

I see some spikes on the low side over 81.6... a couple of hits around 83... nothing above 83 I dont think. So maybe if I raise it to 85 PSI?

I see more spikes above 81 running the eth, than I did with the 93 octane, but they still occasionally happened on 93.

DSX says don't raise it above 600 KPA. Actually they also say not recommended over 500 KPA... but ???? 85 psi = 586 KPA. Will I hurt anything by trying that?

They also mention adjusting the Minimum Fuel Pump DC....

[Joshinator99]

Originally Posted by cjperformance

Its there. The very bottom image. Below the log screenshot. Would repost but not on same comp. Mine is showing psi. I think it works out to be around 560 kpa.

Ok great, I didn’t see that. Most people forget to bump that up from the stock SS settings.

Did you do the JMS in addition to the LT4 in-tank? Situations like the one you’re in are why most shops push the JMS right out of the box. Hard to blame them.

[cjperformance]

There's also this Duty Cycle Base table that looks interesting. I dont want to go messing around too much without knowing what I'm doing.

[cjperformance]

Originally Posted by Joshinator99

Ok great, I didn’t see that. Most people forget to bump that up from the stock SS settings.

Did you do the JMS in addition to the LT4 in-tank? Situations like the one you’re in are why most shops push the JMS right out of the box. Hard to blame them.

Stock LT1 intank pump w/ DSX Aux pump. No JMS.

[wnta1ss]

Originally Posted by cjperformance

Its there. The very bottom image. Below the log screenshot. Here it is again though. 81.6 psi = 563 KPA

Sceenshot does not show which table that is though, is it ECM 6975 or FSCM 6994?

[cjperformance]

Originally Posted by wnta1ss

Sceenshot does not show which table that is though, is it ECM 6975 or FSCM 6994?

OH! Good catch! I only have 6975 updated not 6994. Didn't realize it was in two places. I assume I need to have them both updated?

One is for ECU and one is FSCM? Should they always match?