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Flames Out of the Exhaust

Practical Dyno Tuning

Discussion and questions related to the course Practical Dyno Tuning


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I am curious at WOT what Lambda value can safely be run to give the ever quested after flamethrower exhaust? Does timing need to have extra timing retard applied such as in two step boost building? I have a few customers asking for a tune with that feature.

Best,

Tom

The lambda in full load doesnt make too much difference, retarding the timing in the high rpm low load sites will give the spark, you will need - 20 and as high as - 40 on some engines, you will get bangs and you will get flames with some engines, for cars that don't spit flames you need to be injecting fuel still on the over run

Thank you very much for the information. It makes sense. Would you by any chance have a screen shot of a sample ignition and fuel table?

Best,

Tom

I'm not near the laptop at the moment, I've only done examples on oe ecus, so the load axes is in load request %, usually have to retard the timing on the lowest load site or sometimes the 2 lowest load sites, down to whatever rpm you want it to stop, so if you want the banging only between 3500-7000 ,retard the timing on the 2 lowest load sites from 3500to 7000, on standalone if it was using map as load, best would be to drive the car on dyno and then let off at redline but don't clutch, and watch what ignition sites the car is entering as its on the overrun, sometimes it can hover around different sites as its coasting down, and you will know exactly where to retard, I pulled this image from Google quickly, it will give you an idea

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Thank you for the explanation. It seems very easy to do with little potential damage to the engine. By no means is this something that will be part of most of my tunes. However, from a business perspective there are those customers that will ask for it.

Best,

Tom