FAO Pupp - Missing Emerald pops and bangs: found them!
Discussion
And for anyone who wants to know really... Like most, my pops and bangs had reduced to a bare minimum and I was a bit unhappy with this so after speaking to Joo, had a bit of a play with the ignition and injection maps at 0 throttle position. After a few runs around the local countryside, I seem to have found a bit of a sweet spot and the results are pretty ridiculous... Backing off the throttle at anywhere from 6k down to 1800 revs is met with something similar to the sound of a full blown yankee airstrike. Enough to make even decat Cerbs sound conservative. Even a blip of the throttle between gearchanges or at rest is enough to fire out a machine gun like burst complete with a few flames. In short, its bloody brilliant and has brought me no end of smiles after watching people and animals dive for cover.
It is probably a little too anti-social though being that it is my daily driver, so using the wonders of Emerald I have created 3 maps to switch between while driving. A full blown airstrike at all times map, a airstike but only above around 3/3.5k revs map and a fully silenced map which will never pop/bang no matter how hard you try for normal driving. This provides a almost holy grail like switch enabling me to simply switch on the fireworks whenever I feel like being a noisy bugger without even needing to feather the throttle. If you haven't noticed I'm rather pleased with this new function so I thought I'd let anyone who wants to know what I did to achieve this... And for Pupp who I know was missing his.
Recipe:
- On the events map, uncheck the overrun fuel cut-off box
- On the ignition map, drop everything from 2k up at 0 throttle pos to 0 degrees ignition (I have it stepping up to 7 deg at 1800 revs and reaching normal at about 1450).
- On the injection map, have a play but I found that for some reason there is a big sweet spot at 7ms injector time (std fuel pressure). Put this in from 1600 revs up to the rev limit. If you want the fireworks to only come on higher up in the rev range, put 14+ in instead of 7 until you want them to start (with overrun fuel cut-off still unchecked).
Simple to do, but has great results! Have fun
It is probably a little too anti-social though being that it is my daily driver, so using the wonders of Emerald I have created 3 maps to switch between while driving. A full blown airstrike at all times map, a airstike but only above around 3/3.5k revs map and a fully silenced map which will never pop/bang no matter how hard you try for normal driving. This provides a almost holy grail like switch enabling me to simply switch on the fireworks whenever I feel like being a noisy bugger without even needing to feather the throttle. If you haven't noticed I'm rather pleased with this new function so I thought I'd let anyone who wants to know what I did to achieve this... And for Pupp who I know was missing his.
Recipe:
- On the events map, uncheck the overrun fuel cut-off box
- On the ignition map, drop everything from 2k up at 0 throttle pos to 0 degrees ignition (I have it stepping up to 7 deg at 1800 revs and reaching normal at about 1450).
- On the injection map, have a play but I found that for some reason there is a big sweet spot at 7ms injector time (std fuel pressure). Put this in from 1600 revs up to the rev limit. If you want the fireworks to only come on higher up in the rev range, put 14+ in instead of 7 until you want them to start (with overrun fuel cut-off still unchecked).
Simple to do, but has great results! Have fun
Mine's up at V8D having an engine rebuilt.
I spoke to them about doing a flame thrower map like this.
Their thoughts were that running a map that does this was less healthy for the engine than a map which is 'right'.
They suggested a kit that fits in the exhaust pipe instead.
I can't imagine Joo doing something that would shorten the life of the engine, but V8D know their stuff too.
I know I want the airstrike, but not badly enough to damage things.
I spoke to them about doing a flame thrower map like this.
Their thoughts were that running a map that does this was less healthy for the engine than a map which is 'right'.
They suggested a kit that fits in the exhaust pipe instead.
I can't imagine Joo doing something that would shorten the life of the engine, but V8D know their stuff too.
I know I want the airstrike, but not badly enough to damage things.
Edited by Uncle Fester on Saturday 2nd August 23:01
Gotta say I'd agree with V8D especially as I still runa standard centre box the last thing I need is any more pops and bangs.
Mines perfect, lots of crackle when throttle feathered, or not as much, almost sociable when not feathered.
Best of both worlds all the time.
Bunging unburnmt fuel through the exhaust system is going have a bunch of negative affects on the engine, exhaust and the back of your car.
Mines perfect, lots of crackle when throttle feathered, or not as much, almost sociable when not feathered.
Best of both worlds all the time.
Bunging unburnmt fuel through the exhaust system is going have a bunch of negative affects on the engine, exhaust and the back of your car.
Thats what I thought, this method uses less than a quarter of the normal fuel and only introduces it under zero load. Furthermore I have a stainless full decat exhaust so I'm not bothered about damaging cats or the like. I will probably turn it down a bit by bumping the injector time up to make it less ridiculous but to be honest, 99% of the time it runs with zero pops and bangs and full overrun fuel cut so I'm pretty sure its not going to break...
trackcar said:
Johno said:
Bunging unburnmt fuel through the exhaust system is going have a bunch of negative affects on the engine, exhaust and the back of your car.
Indeed, so it's a good job no-one here is suggesting you do that ..Emerald were talking about achieving this by a map that over fuels just before a soft rev limit set to a lower rpm than normal.
Dave Walker writes for a car magazine. He wrote an article about how he had done this to a Sierra Cosworth using the above method. That magazine gave me the idea and I phoned Emerald about getting it for my Griff.
V8D expressed concern about the bore washing effects of overfueling and petrol contaminating the oil. As they are building my engine, it is their warranty I will be relying upon. Obviously if I run a map that they advise me against, it might compromise that warranty in the event of problems. Therefore I won’t run a map against their advice.
If I understand correctly (and I’m not sure that I do) what you have done is go lean, rather than rich. Then you moved the timing so that the lean mix burns when I presume the exhaust valve has opened. Have I understood correctly?
Normally I think of running too lean as damaging to the engine. Is there any risk to the engine or exhaust system in what you have done, or will it shorten the life of anything?
Can you explain how what you have done works in layman’s terms please?
Funnily enough Nick, I had been playing around with much the same settings and also have three maps on tap now, accessed via a rotary dash switch (reworked TVR fan control, that backlights green, red, or yellow for the three positions that equate to the map colours in the software )... open loop power map as done by Dave Walker in slot 1, an adaptive version of the open loop one with stoich targets all across the range for cruising in 2, and a version of the adaptive one that I'm playing with for overrun fireworks in 3. So far I'm getting odd big cracks, but have yet to find the constant crackle I had. May yet retard the spark into ATDC territory (ie -ve figs on the map), just to see what occurs 
When you say 7ms BTW do you mean 7 in the map table? The figs in the table don't equate to actual ms do they? There's clearly a fuel/air ratio that fires off best (before changing ECU, it used to show something like 19.5 AFR when popping but though I've managed to replicate that, it's not behaving the same. Think the wasted spark is the key here and I suspect the 'extra' spark is now killing any lingering unburned charge that would otherwise cause the crackle.
)... open loop power map as done by Dave Walker in slot 1, an adaptive version of the open loop one with stoich targets all across the range for cruising in 2, and a version of the adaptive one that I'm playing with for overrun fireworks in 3. So far I'm getting odd big cracks, but have yet to find the constant crackle I had. May yet retard the spark into ATDC territory (ie -ve figs on the map), just to see what occurs When you say 7ms BTW do you mean 7 in the map table? The figs in the table don't equate to actual ms do they? There's clearly a fuel/air ratio that fires off best (before changing ECU, it used to show something like 19.5 AFR when popping but though I've managed to replicate that, it's not behaving the same. Think the wasted spark is the key here and I suspect the 'extra' spark is now killing any lingering unburned charge that would otherwise cause the crackle.
Uncle Fester said:
trackcar said:
Johno said:
Bunging unburnmt fuel through the exhaust system is going have a bunch of negative affects on the engine, exhaust and the back of your car.
Indeed, so it's a good job no-one here is suggesting you do that ..Emerald were talking about achieving this by a map that over fuels just before a soft rev limit set to a lower rpm than normal.
Dave Walker writes for a car magazine. He wrote an article about how he had done this to a Sierra Cosworth using the above method. That magazine gave me the idea and I phoned Emerald about getting it for my Griff.
V8D expressed concern about the bore washing effects of overfueling and petrol contaminating the oil. As they are building my engine, it is their warranty I will be relying upon. Obviously if I run a map that they advise me against, it might compromise that warranty in the event of problems. Therefore I won’t run a map against their advice.
If I understand correctly (and I’m not sure that I do) what you have done is go lean, rather than rich. Then you moved the timing so that the lean mix burns when I presume the exhaust valve has opened. Have I understood correctly?
Normally I think of running too lean as damaging to the engine. Is there any risk to the engine or exhaust system in what you have done, or will it shorten the life of anything?
Can you explain how what you have done works in layman’s terms please?
what you're on about with emerald is popping and banging on a soft cut limiter like launch control so the engine is artificially prevented from revving because you're cuting the power on the soft cut, but introducing an excess of fuel so that gets burnt down and out the back of the exhaust as a series of flames, this would be damaging if you held it in this state for any length of time, so use it sparingly.
Pupp said:
Funnily enough Nick, I had been playing around with much the same settings and also have three maps on tap now, accessed via a rotary dash switch (reworked TVR fan control, that backlights green, red, or yellow for the three positions that equate to the map colours in the software )... open loop power map as done by Dave Walker in slot 1, an adaptive version of the open loop one with stoich targets all across the range for cruising in 2, and a version of the adaptive one that I'm playing with for overrun fireworks in 3. So far I'm getting odd big cracks, but have yet to find the constant crackle I had. May yet retard the spark into ATDC territory (ie -ve figs on the map), just to see what occurs
When you say 7ms BTW do you mean 7 in the map table? The figs in the table don't equate to actual ms do they? There's clearly a fuel/air ratio that fires off best (before changing ECU, it used to show something like 19.5 AFR when popping but though I've managed to replicate that, it's not behaving the same. Think the wasted spark is the key here and I suspect the 'extra' spark is now killing any lingering unburned charge that would otherwise cause the crackle.
Yes I meant 7 in the map table... I thought this equated to injector time in milliseconds? I may be wrong though, just thought that if the ign table = degrees btdc, the inj table must have values as well... )... open loop power map as done by Dave Walker in slot 1, an adaptive version of the open loop one with stoich targets all across the range for cruising in 2, and a version of the adaptive one that I'm playing with for overrun fireworks in 3. So far I'm getting odd big cracks, but have yet to find the constant crackle I had. May yet retard the spark into ATDC territory (ie -ve figs on the map), just to see what occurs When you say 7ms BTW do you mean 7 in the map table? The figs in the table don't equate to actual ms do they? There's clearly a fuel/air ratio that fires off best (before changing ECU, it used to show something like 19.5 AFR when popping but though I've managed to replicate that, it's not behaving the same. Think the wasted spark is the key here and I suspect the 'extra' spark is now killing any lingering unburned charge that would otherwise cause the crackle.
Very impressed with the different coloured backlit map switch. I just have a rotary switch on the side of the steering column but I have on occasion forgotten which map I'm on so some sort of indicator would be a great idea. I was thinking of making a 3 way toggle switch with LED indicator for the dash at some point but not sure just yet...
I just have to get my adaptive map working again now as my lambda keeps dropping out of tune. I think it may be a faulty calibration button as it seems to keep calibrating its self in the exhaust perhaps when going over big bumps... I'll get it sorted soon though as I'm looking to put in a dash gauge to view while driving.
@ Uncle Fester: Yeah Dave told me to do a soft cut rev-limiter as well but I didn't like the idea... Doing it this way not only produces much better effects, but it saves fuel and doesn't harm your engine. As you've said, it burns small amounts of fuel with the exhaust valves open when the engine is in overrun state and therefore under no load. Neat little trick actually, well done Joo!
trackcar said:
Uncle Fester said:
trackcar said:
Johno said:
Bunging unburnmt fuel through the exhaust system is going have a bunch of negative affects on the engine, exhaust and the back of your car.
Indeed, so it's a good job no-one here is suggesting you do that ..Emerald were talking about achieving this by a map that over fuels just before a soft rev limit set to a lower rpm than normal.
Dave Walker writes for a car magazine. He wrote an article about how he had done this to a Sierra Cosworth using the above method. That magazine gave me the idea and I phoned Emerald about getting it for my Griff.
V8D expressed concern about the bore washing effects of overfueling and petrol contaminating the oil. As they are building my engine, it is their warranty I will be relying upon. Obviously if I run a map that they advise me against, it might compromise that warranty in the event of problems. Therefore I won’t run a map against their advice.
If I understand correctly (and I’m not sure that I do) what you have done is go lean, rather than rich. Then you moved the timing so that the lean mix burns when I presume the exhaust valve has opened. Have I understood correctly?
Normally I think of running too lean as damaging to the engine. Is there any risk to the engine or exhaust system in what you have done, or will it shorten the life of anything?
Can you explain how what you have done works in layman’s terms please?
what you're on about with emerald is popping and banging on a soft cut limiter like launch control so the engine is artificially prevented from revving because you're cuting the power on the soft cut, but introducing an excess of fuel so that gets burnt down and out the back of the exhaust as a series of flames, this would be damaging if you held it in this state for any length of time, so use it sparingly.
Told I'm worng once, then I think that was corrected. Just wanna make sure I was right in the first place ?. Not something I'd want to do personally with my set up, but each to their own.
Huh? no .. we're talking about taking fuel OUT of the fuel map to make it pop and bang on overrun, not adding it. Adding fuel to a weak mixture STOPS the pops and bangs. Making the mix weak on overrun is what creates the pops and bangs. People seem to be under the impression that it's an excess of fuel that makes the overrun pops and bangs, this is NOT true.
Edited by trackcar on Monday 4th August 00:12
Thanks Joo, even happier now as that had been my understanding all the time and i was beginning to question my whole understanding of what made an exhaust pop and bang in the first place !
When my S had a hole in the servo it used to send 2foot flames out of the exhausts, certainly not something I wanna replicate with the Griffith everyday.
Cheers !
When my S had a hole in the servo it used to send 2foot flames out of the exhausts, certainly not something I wanna replicate with the Griffith everyday.
Cheers !
Edited by Johno on Monday 4th August 08:48
Cool, obviously I won't be running the map all the time as it would just get annoying, but for the odd tunnel and irresponsible moment its a great laugh to have on a switch. I run normally with the fuel-cut off set which means 0 pops and bangs under all circumstances which is much more sensible!
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