To answer the original question.....its fine. on ANY vehicle tip in will always show a lean spike and then drop down to an acceptable level. The fuel has to catch up.

 

In naturally aspirated engines powered by octane, maximum power is frequently reached at AFRs ranging from 12.5 to 13.3:1.
So since our engines are more efficient wouldn't a slight leaner mixture reading at the exhaust be OK.
plus the area a person lives/drives in can vary the AFR due to high/low moisture putting higher/lower O2 pushing in exhaust

 

Has anyone found a wideband and smarts unit for our ECU's that outputs a "still compliant" 0-1V signal to the ECU and a 0-5V to a separate cockpit gauge?

 

Don't they all? My Innovate LC-1 has a simulated narrowband output built-in. I have never used it. I welded in a new bung on each down pipe to be able to install the WBO2 into either side.

 

I tried with a plx wideband before I had a bung welded into the downpipe. It worked ok for a little while, but then started to get an o2 sensor heater code. I also tried to get closed loop enrichment under boost with a Split Second enricher device and could not get it to fool the ecu. Even stumped the techs at SS. The guy who put the Rotex in his NA could not get the Aem piggyback to simulate the narrowbands correctly either. There is something funky about the way this ecu uses the sensors......

 

So I installed the SL55 pump and new filter today drove it for a little while and my long term fuel trim is 0.78. Guess it worked.

Yes the fuel line clips were trouble until I figured out how to get them off.
Yes the lines were stuck on and a *****.
Tried to clamp the lines, failed. Nice gas bath.

Think she is ready for me to install the NW manis

 

Did you install the adjustable pressure regulator?

 

No, stayed with the stock replacement filter.

 

This is a somewhat lazy post......'cause I didn't want to troll through all the history...
1) So how does 0.78 compare to your pre-SL55 figures?
2) without trying to reopen a can of worms, I recall a recent thread/discussion that indicated LTFT aren't really a representation of WOT performance since it ain't in closed loop at WOT - when an SL55 pump would really count.??

b22b

 

LTFT was about 4. WOT is where it's important and I haven't tried that yet. Unfortunately I don't have a wide band sensor. I'll have it re-tuned as well after I install the big manis. I'm only running the 65mm pulley so I'm thinking it will work well. Hopefully.

 

So you stayed with a stock SRT6 regulated filter??

 

Correct. I did not want to go the separate in-line regulator route.

 

Therefore your fuel pressure will always be regulated by the filter at the preset range of 54-58 PSI (these figures have been mentioned here on the forum). I'm not sure what you have gained by installing the SL55 pump other than a more constant fuel pressure at WOT?
Even with the SL55 pump with OEM filter my fuel was dropping off sharply at 5600rpm until I installed the AFPR. Then I still needed to increase the pressure up to 68PSI to solve my lean issues.

 

This is my understanding from the many posts on the subject. You are running a 62mm pulley where as I am running a 65mm. Others have said the extra constant pressure will solve problems with the 65. If I were to go smaller then I would need to change the regulator. At least that's what I read and am hoping it works.

 

Has anyone thought about or have used a fmu system to help the air to fuel ratio here a pic and details I've been thinking About it any thoughts ? image.jpg

 

Here's a pic of the unit image.jpg am debating about using this if I go smaller or stacked I'm only running the EC 65mm pulley but hey might be useful for any pulley set up

 

My understanding is that with the 65mm you really don't need any fuel upgrades. Since you have added the SL55 pump, I'm questioning whether you would see any benefits since the filter is still regulated at the factory setting?? In essence you have added a pump capable of higher flow but you are still restricting the flow due to the stock filter. Have you really changed anything?

 

There has been a lot of discussion on this. Some have said it solved their lean problems with the idea that it will not fall off in the upper rpm range and will maintain constant pressure. Some have also said it has the ability to flow more volume at the same pressure as the stock pump but I don't know about that.

 

It makes sense that if the stock pump is dropping pressure at WOT, the OEM pressure regulator will be wide open to try to achieve its goal, but the pump ain't up to it (reportedly)....and your fuel supply (pressure) will start to drop - maybe only a few psi and maybe only at WOT - but enough to affect AFR.

Putting the bigger pump in would maintain the line pressure better and the OEM pressure regulator might not need to be wide open any more t achieve its set point....

my2c