So i have been playing with speed density (9635variant) for the last few months and have it pretty dialed in for the most part. The thing that is getting me is that I have a very lean spot when I first tip in at 100kpa around 14-16 afr, but when I am part throttle past 100kpa my wideband shows 10.0.

I have been playing with a few of the setting but nothing seems to get it worked out. I have attached two data logs one with a full pull i did today and the other is a part throttle run.

Any help would be much appreciated.

 

The load you set the in boost too is too high it looks like. But more importantly than that is the fuel map itself. Its dropping to 11.6 AFR on the map and if you just lean it out a bit the car wont be so rich there.

So essentially you need a combo of reducing the 100load point by either setting the kpa required higher or reducing the load at the kpa. Lastly set your fuel map to something like 12.5 or so and it should get better.

 

I'm not sure I follow you on the load being to high. I will post the screen shots of my settings street I get out of work.

 

Simply put the load is higher than it should be thus its rich.

To reduce fuel coursely we adjust the load ve table by setting the required psi/kpa higher than it was before at that load so it takes more boost to get to said load thus reducing fuel.

Its not diffulcult by any stretch but it is a bit backwards in the way you have to think about it.

AFRMAP is the variable in your fuel table and it seems like its really rich once it hits 100 load dropping into the 11's.

 

Here are screen shots of my settings. The 11.5 at 100-120kpa is to try to combat the lean tip in that I get when I stab the throttle that you can see in the the log with the fuller pull. I have the timing set pretty conservative right now. My fuel trims are also with in +/-3 for idle and less than +/-1 for cruise.

 

By stabbing and going lean i assume you only mean low rpm conditions because over 3000 rpms it looks fine. I think your focusing too much on the condition of the goes rich and not enough on the goes lean issue.

First your 500-2500 rpm VE is just too low thats why under 3000 rpm your seeing a big lean spike when you give it gas. This is a condition of the VE multiplier as it has more effect with more load meaning more gas bigger problem less gas less problem.

Secondly your map sensor ve map is essentially backwards most cars tune to the note of having kpa HIGHER than the load% yours is the opposite of this case and that's one of the reasons you tuned your RPM VE table soo low.


So lets start over.

1) Set your RPM VE back to stock
89.8438
92.9688
94.5312
95.3125
95.3125
96.875
100
100
100
100
100
100
100
100
100
96.875
96.875

2) Set your load kpa equal to eachother

3) Put the car into full time open loop so you can directly see what its doing. Do this by setting the open loop load tables 1 and 2 to 10 across the board.

4) This is going to cause a rich idle condition which we need to fix. I described this fix in a post follow it except for the reduction in timing part which isn't a problem for you, as you aren't running e85 in cold weather.

https://www.evolutionm.net/forums/8572726-post16.html

Essentially what we will be doing is using maf smoothing to reduce fuel in this idle area where cam profiles and low throttle plate opening create a situation where the table in the rom can't cope with the change in VE. All the steps are easy to follow I ended up at 80% to reduce fuel at idle to be 14.7 again.

You do all these steps and you should be close to being able to drive without major fluctuations in AFR.

When tuning remember these simple tips.

You change map sensor VE when AFR changes with load regardless of RPM. You change RPM VE when at RPM is effecting the AFR. In this way map sensor VE is like the left to right AFR control and RPM VE is like the up and down of the map AFR control. You'll get the hang of it i'm sure.

 

Roadspike thank you for all of the help. Ill set up the new changes tomorrow after work and report back here on how it works out for me.

 

Just be warned its pretty difficult to get it done right.

Its like this balancing act between load and rpm ve you'll hit a sweet spot eventually. Just don't go into closed loop mode until you get it mostly right.

 

Have you tried tweaking any of the acceleration enrichment tables that are available for the 9653 ROM?

 

MrFred I haven't tried messing with those yet. Which ones would I need to play with to get the results I am after.

 

- SyncLoadAccel Compensation vs RPM.

This table provides additional fuel during load increase independent of whether the throttle is moving.

- Async Accel Multiplier vs TPS Delta.
- Async Accel Max Total Contribution During Accel Period
- Async Accel Max Pulsewidth

The first Async Accell table should give you some control over tip-in. The second and third Async Accel tables are limiting values and may need to be increased to get full benefit from the first table.

 

Thanks MrFred. Ill try that out here in a few.