DIY Rom tuning for exhaust pops and backfires W/ romraider

[gonzo]

Originally Posted by Marusich

Overrun enrich delta is a time period after you're off throttle in ms, not rpm.

My intuition is telling me it's measured in delta rpms. That's why it's active when set to a negative number as Grip Ronin says.

[gonzo]

I don't have access to romraider, so I can't look at the full name of those overrun parameters, but if we can increase pulse width during overrun, then the extra fuel should cause the popping sound right when you let off the pedal while in neutral or gear (and cause the overrun condition). You may have to retard timing a bit in the lower loads, but not nearly as much as you did.

Disclaimer: dunno if this works and I'm not responsible for fucked up cars. I'll try it on my own car this weekend

[Marusich]

Originally Posted by gonzo

I don't have access to romraider, so I can't look at the full name of those overrun parameters, but if we can increase pulse width during overrun, then the extra fuel should cause the popping sound right when you let off the pedal while in neutral or gear (and cause the overrun condition). You may have to retard timing a bit in the lower loads, but not nearly as much as you did.

Disclaimer: dunno if this works and I'm not responsible for fucked up cars. I'll try it on my own car this weekend

I could totally be wrong, let me know how it goes.

[Migero86]

Unfortunately, I am going to be removing this from my tune... my car really stinks with this enabled which I assume it would since we are dumping some fuel into the exhaust. Anyone experience that?

I tried it, it was cool, but the stench of fuel in stop and go traffic is a no-go for me. Maybe we can find a different way to do this without the smell.

[Grip Ronin]

i removed the overrun too. i makes the car buck when slightly tipping into the throttle thanks to heavy fueling/ low timing swinging to high timing light fueling.. i just added a bit of fuel in the open loop map at low load and smoothed out the advance transition

[ML]

My unichip does this to my car. After getting on the engine, and then starting to ease off sometimes when I push in the clutch it will pop pretty loud. I'm thinking about ditching it though and just getting a T-cable.

[gonzo]

Originally Posted by Grip Ronin

i removed the overrun too. i makes the car buck when slightly tipping into the throttle thanks to heavy fueling/ low timing swinging to high timing light fueling.. i just added a bit of fuel in the open loop map at low load and smoothed out the advance transition

How did you add fuel? Lowering the AFR? How many columns from the left did you modify in the timing map?

[gonzo]

I changed only my timing to -5 in the lowest load and made the column .06. I'm not getting any loud popping. Could it be because I have the header cat and a high flow cat? Has anyone with two cats tried this?

Edit: changed the column load number back to stock since it wasn't as loud after lowering it to .06

[Grip Ronin]

Originally Posted by gonzo

I changed only my timing to -5 in the lowest load and made the column .06. I'm not getting any loud popping. Could it be because I have the header cat and a high flow cat? Has anyone with two cats tried this?

Edit: nevermind it's there! Just quiet and muffled. I also have e85 so that likely tones it down.

you cant take it to .06 because it switches to closed loop maps at that point which is a different fuel and ignition table. we cant control the closed loop timing yet so we cant do fully off throttle burbling. leave it at .15 and it will pop at very light throttle, while still deceling (thats not a word lol).i added fuel on the regular fuel table just the first column but it makes the car a bit jumpy on transition so ill be removing it

[gonzo]

Originally Posted by Grip Ronin

you cant take it to .06 because it switches to closed loop maps at that point which is a different fuel and ignition table. we cant control the closed loop timing yet so we cant do fully off throttle burbling. leave it at .15 and it will pop at very light throttle, while still deceling (thats not a word lol).i added fuel on the regular fuel table just the first column but it makes the car a bit jumpy on transition so ill be removing it

Thanks a lot. How about retarding timing in the "base timing idle (in gear)(above speed threshold)"? Does the ecu use this timing table as soon as you let off the throttle? Is that what "idle mode" is?

[Grip Ronin]

Originally Posted by gonzo

Thanks a lot. How about retarding timing in the "base timing idle (in gear)(above speed threshold)"? Does the ecu use this timing table as soon as you let off the throttle? Is that what "idle mode" is?

im not really sure what that does because the ecu doesnt know what gear a manual trans is in. maybe a automatic feature? i adjust ignition base (normal).the first time you flash the car will be on the safe mode map until operating tempature

[Proof]

[ame="http://vimeo.com/90468186"]Nameless over pipe/front pipe combo with 3" alxeback on Vimeo[/ame]

[gonzo]

Originally Posted by bee_are_zee

The next tuning adventure should be to find out if we can get ghost cams at idle...

After looking up what this sounds like...

YES

FRS with ghost cams at idle

[bee_are_zee]

I had some success messing with cam overlap at idle. But for some reason I had to give just barely some input on the pedal before the timing would shift. When the car is at idle does it pull from a different timing map?