Adv Multiplier Dropping from 1 to .7-.88
 

Currently running OFT stg 1 93oct in MD with 93oct fuel. Just a catback installed and will be switching to stage 2 with the OFH this week or next.

I'm a complete newcomer to tuning. That being said I'm reading a lot about how it works and I've seen in a few threads to pull timing by 0.3deg increments until the AM stays at 1.

My Question:

In RomRaider, I go to Ignition Timing - Advance -> which table? Base A, Base B, etc?

Also, how long should one wait after flashing to decide if extra tuning is needed? I flashed last night and with my AM at 1 the car felt like it had 20 more hp/tq but today feels like it did before i reflashed (all i changed was LC). Can someone walk me through how to fix this?

Wait for your LTFTs to level out. Base Timing B. If you see a consistent knock of -0.8 in a certain cell, take out half of that (0.4). Repeat until it goes away.

Consistent knock of -.8 meaning the flkc value consistently showing up at a certain RPM range vs engine load?

yes if you see knock consisently at a load rpm point pull some timing from Base Timing B table.

Assuming your maf scaling and fueling AFR is ok

also try some different brand fuel some are better than others.

you can also try modding the pi/di ratio tables cold/warm/hot as per below if your seeing higher rpm knock 5000-7000, so you run full DI till 7200 instead of 5200, the lower load changes are for idle stability and takeoff from idle stability

if it below 3000 then just pull a bit of timing

http://www.ft86club.com/forums/attac...1&d=1433920729

Have you seen anything suggesting that running 100% DI that high into the range is beneficial? I thought that there wasn't any improvement and actually running some PI helps the mixture.

Don't forget that the ECU pills timing at a minimum set value, usually -0.7 or -1.05. You can check in the map. If you see smaller retard values it's actually restoring back towards 0. Not all negative values in the log correspond to the onset of knock which is why you want to work out the nearest moment that caused the ECU to pull timing. All timing changes on the maps are in 0.35 degree multiples.

On good fuels it makes little difference, on our fuels it appears to work quite well and on south africian fuels (95ron) those guys said they could add back in up to 2 degrees timing in some areas by going full DI

Yes i don't get concerned about anything thats not over -0.7.

see link here from moto-mike
http://www.ft86club.com/forums/showp...2&postcount=17

I agree their no direct power increase due pi/di in it but if you can add timing back in as a result it would appears it worth doing. (and your not maxing out DI as mike says unlikely on NA petrol tune. Gets close on E85 though.

what is your LTFT %?? at idle??

less than 5% usually unless IAT varies widely
or my E% changes 20% or more

http://datazap.me/u/steve99/e85-v7-l...ata=9-10-15-26

http://datazap.me/u/steve99/mt-glorious?log=0&data=1-7

i wandering about DI issues that let the ecu add LTFT

Many thanks guys. My LTFT evened out while I was driving this evening and it only took one adjustment to get it stable @ 1 again. With that said, here's another question:

If I were to add timing, is it as simple as adding .1-.5 per cell? Is there a certain pattern? Is there a location of a general guide of how to do your own custom tunes so I don't bother you guys? My background is in EE and control theory.

I'm not sure where exactly you'd decide where to add timing but don't forget- just because your IAM is at 1 during street driving, doesn't mean you won't have knock during hotter days, sustained hard street driving or autox/track. My IAM was at 1 for a long time even with hard street driving, went to an autox event and my IAM dropped down to .8.

As far as pulling/adding timing, Steve99 has a lot of written guides on editing tunes and what to look for, and I also have a basic guide on changing Base Timing in Romraider.

the minimum add/subtract is 0.35 degrees

on petrol you will generally get knock before you get to MBT (max torque) but on E85 you can often advance the timing past MBT before knock so you need to check your actually making more power .

My IAM was dropping today during the hot ass humid weather we have going on in Maryland. stayed consistent at 1 this evening... maybe need to adjust during the day in the heat?

best to adjust knock for average intake air temps then use IAT retard tables to retard only when temps high

see here note his tables displaying the changes not the absolute values, make sure you put in the - signs in the IAT temp compensation table else it will add timing then temps hot :-)

http://www.ft86club.com/forums/showt...47#post2216047

I had tried running more DI % on an NA car and it made little difference.

I wonder whether making the DI inject a little later would be more beneficial with regards to charge cooling? I've tried to read up on DI timing and all I got was that ideal charge cooling occurs if injecting at ~120deg before TDC.

So, in RR terms that would be 330, right? Would it provide the best benefit on the hot tables only?

Do not go changing those tables without any idea what you're doing. You would do all the tables as that's how they are stock, I have no idea what would happen if you just did one table, where the switch over is etc.

As it stands the DI timing tables, I believe, show start of injection BTDC so 360 is at TDC at the start of the intake stroke.