DIY Rom tuning for exhaust pops and backfires W/ romraider

[Songha]

The only way to get it to pop is to lightly hold the throttle after letting go or decel. This what it seems like. It gets annoying when cruising sometimes so I have only the fields above 2,000 changed. I also have the fields for column 0,20 set to "-5" from 2,000 to 6,400.

[elBarto]

Best is that you don't have any cats. So you need to change the header and frontpipe to catless versions. Otherwise it's possible that you melt the cats.

Edit: same answer as the rest, tapatalk didn't show me the next page.

send using the coffeemaker

[Metal_88]

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,

Hi all, i've been reading this thread cause I'd like to have some pops too

Eddie, I used the parameters you posted here, but on my GT i got absolutely no pops, I only got them with Ignition timing B map with 0.15 load engine and -10 degrees, pressing a bit of throttle. Is it possibile there is something am I missing? I use BRZEDIT to edit my maps, I see some differences with the ones you all are posting here. Now I made a new map, gonna test tonight and post here if it works.
I'd like to hear pops when releasing the throttle above 3000rpm , so you can drive as usual...

Thanks to all for now

[eddieflyinv]

@Metal_88
Not sure how familiar you are with rescaling the table axis but I have done that since, and it works well for gaining more control of the ignition retard at higher rpm
I only ever messed with the 176 and above temp range row, as I dont like throwing wierd shit at the car while its warming up still and there are all kinds of other compensations in effect.
My suggestion, get rid of the duplicate columns, (example 550 to 750 takes up 4 columns and are all the same, so just go with 1 column of 750 @ 14.1) and shift everything over, you can free up 5 columns to play with rpm ranges you want and different negative values in those cells to produce more pronounced pops and bangs wherever youd like.
As for BRZedit, I have never seen or used it so unfortunately I am no help there. Just be careful and dont change something if youre not sure what its for.
Should probably apologize to a few people here who personally pm'd me about this stuff. Super busy lately, havent toyed with this in a while, but I do plan to soon as I have gone catless since that post, but worth mentioning, I was getting great results with rescaled axis and stock header so it can only get better/louder

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[eddieflyinv]

@504 @sqd @dhuang finally got around to this.
Just an example of my current settings for overrun, not too much has changed from my previous experiment, mind you im just starting playing with it again

First 3 tables are located in Fueling - Overrun Folder
- Overrun Initial Enrichment @ 1.2
- Fuel Cut Threshold @ 6000
- Overrun Enrichment Activation Delta @ -15
Last 2 Tables found in Ignition Timing - Advance Folder
- Rescaled the Base Timing Idle (In Gear Above Speed Threshold) table, like I mentioned before, my preference was for this to only start occurring when the engine was almost warmed up
- Raised the value in Base Timing Idle Vehicle Speed Threshold table, this helped quite a bit to avoid low speed jerkiness (10km/h because canada)

As mentioned before, may have to play with the amount of Overrun Enrichment and the values used to retard timing in the Base Timing Idle table, previous tunes were Stage 1 with Stock headers and catless overpipe, and with the stage 2 tune and no cats I have reduced Initial Enrichment from 2.8-1.8 to 1.2
Things acheived
- Lots of explosive crackles at high rpm lift,
- Crackles between shifts (with slight delay, seems to be more time related than rpm related, so OL/CL transition delay settings may potentially alter that)
- downshift bangs, lately they seem to be singular (only had this tune up again since last night) but theyre loud, though they are not rpm limited anymore, (never used to get them above 3krpm before)
- feathering popping/crackle, find that spot and it will pop endlessly, often on tip in there is a slight initial crackle, and if you have your cruise on going down hill your car will sound like automatic gunfire the whole way down 🙊 not sure if the tip in crackles can be gotten rid of, seems to be table switching delay so maybe messing with the OL/CL transition delays could reduce or eliminate that as well.

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[Songha]

Originally Posted by eddieflyinv

@504 @sqd @dhuang finally got around to this.
Just an example of my current settings for overrun, not too much has changed from my previous experiment, mind you im just starting playing with it again

First 3 tables are located in Fueling - Overrun Folder
- Overrun Initial Enrichment @ 1.2
- Fuel Cut Threshold @ 6000
- Overrun Enrichment Activation Delta @ -15
Last 2 Tables found in Ignition Timing - Advance Folder
- Rescaled the Base Timing Idle (In Gear Above Speed Threshold) table, like I mentioned before, my preference was for this to only start occurring when the engine was almost warmed up
- Raised the value in Base Timing Idle Vehicle Speed Threshold table, this helped quite a bit to avoid low speed jerkiness (10km/h because canada)

As mentioned before, may have to play with the amount of Overrun Enrichment and the values used to retard timing in the Base Timing Idle table, previous tunes were Stage 1 with Stock headers and catless overpipe, and with the stage 2 tune and no cats I have reduced Initial Enrichment from 2.8-1.8 to 1.2
Things acheived
- Lots of explosive crackles at high rpm lift,
- Crackles between shifts (with slight delay, seems to be more time related than rpm related, so OL/CL transition delay settings may potentially alter that)
- downshift bangs, lately they seem to be singular (only had this tune up again since last night) but theyre loud, though they are not rpm limited anymore, (never used to get them above 3krpm before)
- feathering popping/crackle, find that spot and it will pop endlessly, often on tip in there is a slight initial crackle, and if you have your cruise on going down hill your car will sound like automatic gunfire the whole way down 🙊 not sure if the tip in crackles can be gotten rid of, seems to be table switching delay so maybe messing with the OL/CL transition delays could reduce or eliminate that as well.

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I have a tune saved under your name with your previous setup. Gonna try this out, I've been wanting those single gunshot BANGs. Ive been able to get them with the Base Timing mod but not very easily.

[dhuang]

Originally Posted by eddieflyinv

finally got around to this...

Thanks for this! Will you be making a video? I'd love to see and hear the results.

Also, I'm OFT Stage 2 UEL right now with the stock front pipe w/ cat. Will I have similar results?

[eddieflyinv]

Working out of town so probably not till the weekend lol
And not exactly the same but still similar to my original results with stock header which were still pretty damn good,
If following the above exactly doesnt get you what you want, play with it a bit, i had gone up to as far as 2.8ms enrichment, but found around 2.1-1.8 what i liked best, and where I have -5 in base timing idle you can also go further negative for more aggressive retard, or go more positive for really enjoyable burbling noises over pops

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[snapplepat]

@eddieflyinv
I'm new to this whole romraider thing... I did etuning with shiv and just wanted to poke around in romraider and see what its all about and maybe add some pops! I was going to do the same thing you did in your most recent post but my tables and even my folder selection seems much different than yours.

So my question is, am I doing something wrong? I have, from what I can tell, the latest A01C definition file (v2.076)

[eddieflyinv]

@snapplepat you need different definition files
http://www.ft86club.com/forums/showthread.php?t=83945
At the bottom of the first post there are attached files, download the one called "WW Definitions v115" and find the definition file for your rom in there,
Go into your definition files manager and delete the one youre currently using, and replace it with the correct one from that file in the USDM folder. They have the same names as original OFT xmls, so I renamed mine WW OFT ZA1JA01C
Those defs will have the required tables defined and youll be good to go 👍

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[lizbrayan]

Ive had this going on in my car dor a few months now and ive noticed once i go a little under half a tank of gas the loud gunshot pops turn into more burbles. Idk if this is true for the rest would love to see if this happens to anyone else

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[Kaotic Lazagna]

I have plenty of pops with the OTS stage 1 91 tune and just a Berk Technology track pipe (dual exit).

Have to turn up your volume high for this one since it's from my dash cam:
[ame="https://www.youtube.com/watch?v=6voezSVXS9g"]FR-S Exhaust Pops - YouTube[/ame]

And on start up with a slight blip of the throttle (engine is not cold, btw):
[ame="https://www.youtube.com/watch?v=eQXR8LNRQPU"]Exhaust Pops Start Up - YouTube[/ame]

[Songha]

Not sure about anyone else but some of the pops I get are like my buddy's WRX TR's anti-lag. His shoots fire, I'll never know since I only get them after load while driving. At a standstill it's alright imo.

[eddieflyinv]

Originally Posted by lizbrayan

Ive had this going on in my car dor a few months now and ive noticed once i go a little under half a tank of gas the loud gunshot pops turn into more burbles. Idk if this is true for the rest would love to see if this happens to anyone else

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Never noticed that myself lol weird..

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