What to tune first? MAF, VVE, TIMING- Does it matter?

[Cringer]

awesome! i think im ready to get started then! i wanted to make sure how to copy and paste because i would have definitely messed that up with the multiply percent option. once i copy and paste. how can i tell that i am going in the right direction? i pasted into the VVE table and done a rough estimation that at idle, the VVE is out around 28 percent. does this seem common?

I am not sure about the idle issue...do you have a cam with a long duration? Lots of things can be going on here at idle...you have the base running airflow, which should handle this area in theory...not the VVE table, but you also have the MAF and then you have the Dynamic Airflow High RPM disable. Either way you'll get the hang of it as you make changes and collect logs.

Personally, I made my own spreadsheet to tackle the VVE tuning and I really focus on on the VVE zone at a time. This way after I copy/paste the histogram, either by full or half percent and then calculate the coefficients, I can see if that caused an unnatural dip or bubble that is going to mess up other areas of the zone. I also have gone through re-doing the RPM/MAP zones several times to fit what works for my combination.

[LS ROB]

yeah the car is cammed. i took a couple logs today and pasted into the vve table. it looks a little "peaky" but ill give it another goVVEstep1.4braf.hpt

[GHuggins]

Just remember to keep things smooth. I just guestimated on yours based off of the transitions it was making. You can plug this in and go from there. The more driving data you collect and fill in the better the transitions will become.

[LS ROB]

ill flash it in and log some more drive time. thanks brother

[LS ROB]

Andrew, how would i set up that histogram to compare VVE vs MAF?

[blindsquirrel]

https://forum.hptuners.com/showthrea...ation-for-gen4

[LS ROB]

Thanks squirrel. I have seen this come up before, so, i guess ill be getting a little more familiar with my scanner functions.

[LS ROB]

steadystatetune.hptsteadystate4.hpl

I did a few logs today and have some questions. 1.) When trying to dial in MAF; do you want to do this at lower rpm, higher rpms, or does it matter as long as you get smooth pedal transitions?

2.) Is the jerky motion at low rpms I now feel, due to not smoothing enough when tuning VVE?

3.) How do you know when you need bigger injectors? Throwing in this other log that says injector duty% is 93.1 and I didn't even run it up to 7k steadystatetune.hpl


Thanks

[eXo3901]

1.) When trying to dial in MAF; do you want to do this at lower rpm, higher rpms, or does it matter as long as you get smooth pedal transitions?

2.) Is the jerky motion at low rpms I now feel, due to not smoothing enough when tuning VVE?

3.) How do you know when you need bigger injectors? Throwing in this other log that says injector duty% is 93.1 and I didn't even run it up to 7k

Smooth, steady state data. RPM will be whatever it needs to be to get to the various Hz ranges of the MAF.

Could be or timing or O2 swings.

Depends, but 80% on port injection is generally where you start to consider a injector change.

[LS ROB]

Thank you!

[LS ROB]

Ok. So when logging VE, MAF, & DYNAMIC, should all of these read exactly the same or will they be a little different? Im not in front of my laptop right now but if I remember correctly, my MAF & DYNAMIC are close but my VE reads slightly higher. Example: MAF 93, DYNAMIC 97 & VE 112 is that normal or how close should they be?

[Cringer]

Ok. So when logging VE, MAF, & DYNAMIC, should all of these read exactly the same or will they be a little different? Im not in front of my laptop right now but if I remember correctly, my MAF & DYNAMIC are close but my VE reads slightly higher. Example: MAF 93, DYNAMIC 97 & VE 112 is that normal or how close should they be?

Can you post the HPT and HPL?

[LS ROB]

Out of town right now so no access to the laptop. I was hoping that it could be a pretty easy answer or at least get me headed in the right direction with some general information.

[dhoagland]

Ok. So when logging VE, MAF, & DYNAMIC, should all of these read exactly the same or will they be a little different? Im not in front of my laptop right now but if I remember correctly, my MAF & DYNAMIC are close but my VE reads slightly higher. Example: MAF 93, DYNAMIC 97 & VE 112 is that normal or how close should they be?

Here is a screen shot of mine, this is a hard/quick stab of the throttle. This is the only time in this log that these readings are not within 1-2 of each other.VE-MAF-DYN.JPG

[dhoagland]

Here is the same log Zoomed out 30 minutes

[LS ROB]

quick log.hpl here is a quick log i took this evening.

[LS ROB]

thank you. looks like i may be heading in the right direction

[dhoagland]

quick log.hpl here is a quick log i took this evening.

Looks pretty darn good!

[LS ROB]

thanks. ive got a manual transmission so i was hoping to get a little less bucking around 1500rpm. id like to get it down to at least 1200rpm but i dont know if its possible with a cammed car or if im bout as good as it gets and need to move on to timing. guess ill keep at it a few more times and see what happens. should VE be grouped a little tighter with MAF & DYNAMIC?

[dhoagland]

I'm no expert on the "Grouping" but I believe you are pretty good. From what I understand sometimes the dynamic will bias towards MAF (more steady state) then sometimes more towards VE (Transient states)...

Looking at your log I see Timing jumping when Throttle, MAP, MAF RPM, all seem steady. I'm wondering why and if this is the bucking you are feeling.