DIY Rom tuning for exhaust pops and backfires W/ romraider

[steve99]

B01C will run in all manual cars up to 2016 ie including F40C

so what you need is waynos B01C rom calid hacked to F40C and matching B01C def hacked to F40C if you have oft

if you have tactrix just flash the B01C and use standard B01C defs

[aagun]

Originally Posted by gypsy_seven

I think i may be in the same boat as @guybo I have f40c cal id and when i open the same tables that @snapplepat posted my tables for Base timing idle (in gear)(above speed threshold) only has one row and after 2000 rpm it looks to go crazy. however this is off my current tune on my car. stg1 with the grimmspeed intake scaless adjusted and has been running fine for 5k miles. Here is a screen shot of what i mean.

Is it possible to modify the tables to get the crackle or should i stay away from them?

this is old issue. can be fix by edit xml file offset to 9 . before 16

[eddieflyinv]

@steve99 thanks alot
About hacking the B01C to F40C for OFT; ive looked at my oft rom in a hex editor (700C) and what ive noticed is the 3rd instance of ZA1J is B01C, the other 2 are 700C.
So is hacking the rom done by simply changing the first 2 instances of B01C to 700C ?
Or in guybos case, B01C to F40C ?

Sent from my LG-H812 using Tapatalk

[BXRCHTR]

So I am trying to achieve flames with my 2013 Subaru BRZ 6AT Full catless straightpipe with Invidia headerback. What am I supposed to be doing? Changing the fuel overrun? OP Posted this on his update "just an update don't mess with fueling or overrun..." Should I still add those in with my tune?

[bababooey]

do pops or backfire noises mess up the engine? asking b/c was in parking garage over weekend, gave it a lil gas while pressing start button, got a loud pop upon startup. OTS stg 2 catless header stock front pipe, AB-M out back. im not interested in fiddling with the tune, just curious.

[Bisofication]

Originally Posted by bababooey

do pops or backfire noises mess up the engine? asking b/c was in parking garage over weekend, gave it a lil gas while pressing start button, got a loud pop upon startup. OTS stg 2 catless header stock front pipe, AB-M out back. im not interested in fiddling with the tune, just curious.

Basically, those pops occur from igniting the non-burnt fuel that's being dumped in the exhaust system. I had the tune running for about 3 months now without any issues so far. As for that start-up bang, I had it happen a couple of times. I can't find a reason why it could be causing any harm to your engine but I'd suggest to avoid hitting the gas as you're turning the car on as it will turn on just fine without the aid of your throttle.

[brzfl]

Originally Posted by eddieflyinv

Alright I have this working now with no messing around in the Base Timing B table.
I wanted to figure this out so there was no drivability issues in case you hit the 0.15 section of your base timing during normal driving.
I literally Just got this working and tested it for all of 15 minutes so it could use some fine tuning im sure, and im not 100% sure what change did it, but if others want to test and help figure out what works best for different goals that would be awesome.

You will need the fully defined Base Idle Timing (In Gear)(Above Speed Threshold), so I used the OFT Definitions Found Here provided by @Kodename47 - http://www.ft86club.com/forums/showp...&postcount=411

Helpful Links used to figure out what might work
http://www.romraider.com/forum/viewt...10488&start=60 (mostly end of page 5)
http://www.romraider.com/forum/viewt...hp?f=40&t=8411 (read the whole thing, mainly explaining the idea of overrun logic etc)

[IMG][/IMG]

Base Idle Timing (In Gear)(Above Speed Threshold): set @ -5degrees @ 1800rpm @ 176 ECT
Overrun Enrich RPM Delta Activation: set @ -17
Overrun Initial Injector Enrichment: 2.8ms (only set so high to stand out while logging)
Overrun Fueling RPM Resume Threshold: set @ 3500rpm from 176ECT - 230ECT
Overrun Fueling Cut Counter RPM Threshold: Didnt touch it at all (yet..)

This worked extremely well, when off throttle and going to coasting, after a short delay I would get a pop or 2,
between shifts after a short delay I would get a pop or 2 depending on rpm as well,
after decelling a bit, On tip in (rolling back onto throttle) I would get a shit load of pops if I held the throttle at a sweet spot (barely touching it), so almost exactly what the other method did, or If i just got back on throttle quicker it would be just a short tip in pop
most noticeable effect so far is when using heel toe downshift in the lower rpm ranges (2500-3000), the repeated popping and burbling as you drop gears is pretty freaking amazing.
still working on exactly what is causing this to better tune the effect, but I imagine it has alot to do with the base timing idle modifications made, going to play with it a bit more and see what changes to the initial enrichment does.
this was all tested with a stock header (but catless FP and invidia N1), so I am curious to see how the catless guys get on with this,

This should work to get the car to pop without having to feather the throttle according to these settings correct?

The only thing I'm worried about is the Base Timing Idle table going crazy after 2000rpm.

[Kodename47]

Originally Posted by brzfl

The only thing I'm worried about is the Base Timing Idle table going crazy after 2000rpm.

That table doesn't look properly defined.

[brzfl]

Originally Posted by Kodename47

That table doesn't look properly defined.

It was like that in the newest oft maps :\

Any way to fix it or define it?

[aagun]

Originally Posted by brzfl

It was like that in the newest oft maps :\

Any way to fix it or define it?

    <table type="2D" name="Base Timing Idle (In-Gear)(Above Speed Threshold) " category="Ignition Timing - Advance" storagetype="uint8" endian="big" sizey="9" userlevel="4">
      <scaling units="Base Ignition Timing (degrees BTDC)" expression="(x*.3515625)-20" to_byte="(x+20)/.3515625" format="0.00" fineincrement=".2" coarseincrement="1" />
      <table type="Y Axis" name="Engine Speed" storagetype="float" endian="little" logparam="P8">
        <scaling units="RPM" expression="x" to_byte="x" format="#" fineincrement="50" coarseincrement="100" />
      </table>
      <description>This is the base timing in idle mode when vehicle speed is greater than the 'Base Timing Idle Vehicle Speed Threshold' and transmission is not in neutral.</description>
    </table>
    <table type="3D" name="Base Timing Idle (In-Gear)(Above Speed Threshold)" category="Ignition Timing - Advance" storagetype="uint8" endian="big" sizex="10" sizey="2" userlevel="4">
      <scaling units="Base Ignition Timing (degrees BTDC)" expression="(x*.3515625)-20" to_byte="(x+20)/.3515625" format="0.00" fineincrement=".2" coarseincrement="1" />
      <table type="X Axis" name="Engine Speed" storagetype="float" endian="little" logparam="P8">
        <scaling units="RPM" expression="x" to_byte="x" format="#" fineincrement="50" coarseincrement="100" />
      </table>
      <table type="Y Axis" name="Coolant Temperature" storagetype="float" endian="little" logparam="P2">
        <scaling units="Degrees F" expression="x" to_byte="x" format="#" fineincrement="1" coarseincrement="5" />
      </table>
      <description>This is the base timing in idle mode when vehicle speed is greater than the 'Base Timing Idle Vehicle Speed Threshold' and transmission is not in neutral.</description>
    </table>

[brzfl]

Originally Posted by aagun

    <table type="2D" name="Base Timing Idle (In-Gear)(Above Speed Threshold) " category="Ignition Timing - Advance" storagetype="uint8" endian="big" sizey="9" userlevel="4">
      <scaling units="Base Ignition Timing (degrees BTDC)" expression="(x*.3515625)-20" to_byte="(x+20)/.3515625" format="0.00" fineincrement=".2" coarseincrement="1" />
      <table type="Y Axis" name="Engine Speed" storagetype="float" endian="little" logparam="P8">
        <scaling units="RPM" expression="x" to_byte="x" format="#" fineincrement="50" coarseincrement="100" />
      </table>
      <description>This is the base timing in idle mode when vehicle speed is greater than the 'Base Timing Idle Vehicle Speed Threshold' and transmission is not in neutral.</description>
    </table>
    <table type="3D" name="Base Timing Idle (In-Gear)(Above Speed Threshold)" category="Ignition Timing - Advance" storagetype="uint8" endian="big" sizex="10" sizey="2" userlevel="4">
      <scaling units="Base Ignition Timing (degrees BTDC)" expression="(x*.3515625)-20" to_byte="(x+20)/.3515625" format="0.00" fineincrement=".2" coarseincrement="1" />
      <table type="X Axis" name="Engine Speed" storagetype="float" endian="little" logparam="P8">
        <scaling units="RPM" expression="x" to_byte="x" format="#" fineincrement="50" coarseincrement="100" />
      </table>
      <table type="Y Axis" name="Coolant Temperature" storagetype="float" endian="little" logparam="P2">
        <scaling units="Degrees F" expression="x" to_byte="x" format="#" fineincrement="1" coarseincrement="5" />
      </table>
      <description>This is the base timing in idle mode when vehicle speed is greater than the 'Base Timing Idle Vehicle Speed Threshold' and transmission is not in neutral.</description>
    </table>

Wow thank you! I'll try it when I get home as well as try the settings and post how they work out!

[aagun]

Originally Posted by brzfl

Wow thank you! I'll try it when I get home as well as try the settings and post how they work out!

active 2nd table

[modbus]

I just have a catback on my car and made the column change as suggested for the table Base Timing B, however I kept the first two the stock stg 1 tune values and everything higher in the RPMs were -10. This seemed to make the smell of gas when sitting idle go away.

Results:

[itzaustin]

I've noticed this works a lot better with e85. I switch back to 91 and haven't really had much with this. But on e85 with down shifts, and friends following me I was able to shoot foot long blue flames, full catless of course.