Continued Performance Developments from Livernois Motorsports for the Explorer Sport

[jays05]

You have the plugs gapped down? Perhaps blowing out the spark plugs in the higher RPM range.

.025" gap

It feels like overboost + oscillation. I know what spark blowout feels like after running my subie at 30psi on e85.

 

[dcpatters]

.025" gap

It feels like overboost + oscillation. I know what spark blowout feels like after running my subie at 30psi on e85.

I hear ya, I had Evo X MR with similar mods. How cold is it?

 

[vteckiller2000]

It is overshooting target boost I think. Weird that the PID in the tune can't control it...

 

[TouchOfEvil]

I have the same issue, i ran torque with track recorder to figure out the problem.
It's fuel rail pressure.
At 4500rpms the pressure tanks and it has to rebuild that pressure which results in the stutter.
The a/f ratio is very rich, 10.2/1 at times on mine. The average is 10.5-10.7 but hits 10.2 here and there.
It needs to be leaned out like they did for the SHO v7 tunes.
11.2-11.4 would clear it up as the demand on the pump would no longer be so tough.
Another option is to add a boost a pump to get more fuel from the pump and of course you can supplement with meth.
Neither are really needed if the A/F ratio get worked out though. It's just too rich period.
Unless you plan to get more boost/mods later of course as the fuel demands would increase with more boost etc...

Watch the a/f and fuel pressure.
http://youtu.be/v8ucjbgGnXk

 

[Ryan327]

Anyone else having serious power reduction issues now that it is cold? Mine cuts torque right substantially after each shift now. Much slower....

I can't offer much to help, but us guys with the Lund SS tune were having this issue for awhile and it's not related specifically from one tune to the other. Definitely has to do with overboosting and pressure spikes it sounds like. \

I've been gapped down for awhile so I know that had no bearing on the problem for me.

 

[Livernois]

I have the same issue, i ran torque with track recorder to figure out the problem.
It's fuel rail pressure.
At 4500rpms the pressure tanks and it has to rebuild that pressure which results in the stutter.
The a/f ratio is very rich, 10.2/1 at times on mine. The average is 10.5-10.7 but hits 10.2 here and there.
It needs to be leaned out like they did for the SHO v7 tunes.
11.2-11.4 would clear it up as the demand on the pump would no longer be so tough.
Another option is to add a boost a pump to get more fuel from the pump and of course you can supplement with meth.
Neither are really needed if the A/F ratio get worked out though. It's just too rich period.
Unless you plan to get more boost/mods later of course as the fuel demands would increase with more boost etc...

Watch the a/f and fuel pressure.
http://youtu.be/v8ucjbgGnXk

PM received

I have talked to my tuner and we are looking in to this issue as well.

 

[TouchOfEvil]

PM received

I have talked to my tuner and we are looking in to this issue as well.

Awesome!!!! I know i will need meth once the xv1 tune comes out but xv1 or not the current a/f ratio is just too rich. It also leaves a good bit of power on the table so i'm glad the tuner is going to get it worked out for us. Thanks!

 

[Ryan327]

Is that commanded AF on your scans or is that actual from a wideband O2?

 

[TouchOfEvil]

Is that commanded AF on your scans or is that actual from a wideband O2?

It's actual as the ecm sees it. The commanded is usually on point with what the actual shows but at times it shows up richer then the commanded. I did a few pulls with the commanded on there along with the measured but they were while i was running the stock tune to compare vs the other tunes.

If i want to do a vid with a wide band i won't be able to get the torque app in there. I do have a wideband and have ran it and what the ecm shows seems to be dead on or off by a .1 here and there.