Here are the stats of the van I submitted!
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Your immediate error here is zero ignition timing. Pretty much no engine without turbochargers benefits from going below 50, so youâve left a lot of power and efficiency on the table. Even the 0.4 RON you have left in the engine couldâve been used to get a little bit of ignition timing and improve efficiency. The other question I have is how heavy your van is, as thatâll affect fuel economy too.
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Thats one thing I personally dont understand is ignition timing. Are there any guidelines to this that I can reference?
Timing and compression (and a few other factors) affect resistance to knock. In general, n/a engines work best with the timing up quite a bit. Turbo engines retard a few points along with dropping compression, due to propensity to knock, and the fact that turbo engines are already compressing the air/fuel mix.
If you are after max performance, youâll find that your cam profile, fuel used, etc are all going to have a âsweet spotâ for ignition timing. Its usually in the 60-70âs range for N/A, and 50-65âish range turbo. Just watch the HP/TQ, and RON markers (for knock) as you adjust.
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Thankyou for that info, Ill definitely take heed.
How about getting good mpg numbers? Besides lowering cams, leaning the fuel mixtureâŚdoes timing play a vital role?
A shame! 
The injection timer shouldnât be like this! Lanson will trying to figure out in this problem, thus you might orinting on him, at least.
Timing, high compression, low friction pistons, VVT / VVL, gearing (to a point), aerodynamic choices, and (detrimentally to being truly accurate and thus frequently abused) wheel diameter as well as overall tire diameter, in addition to tire type and quality.
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Man I appreciate that.
About a month ago i was wanting some engine tuning help, so I thought id play some of those engine scenariosâŚ
Yep, that was a negative. Needless to say, I cant wait for those to come back.
Thanks that makes sense. Making the fuel mixture more rich increases power by a lot. Just advancing ignition timing though makes the engine knock. The reason I have fuel mixture and ignition timing so low is because of fuel efficiency. I have 29.2 mpg with the current set up, but increasing fuel mixture and ignition timing makes mpg absolutely plummet, and I really didnât want that.
1,536.9 kg is the total weight of the van.
- Donât increase fuel mixture, drop compression instead
- 1537kg is indeed quite heavy for this class of van
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This is actually another characteristic difference between real world and Automation world. The AFR of real cars averages 12-14:1 or so. Youâll find that Automation does best with eco cars near the bottom in the 14-15 range, and turbo you can kick that up to 13-14ish, and see the fuel economy not really shift too much. So itâs not really a match to real life.
Best example is in a previous QFC I judged, I did it almost completely objectively with a massive spreadsheet and slicers,etc. In that, there were several turbo SUVâs running 15.0-1 AFR or close. In real life, the engine would detonate in seconds. Also, Automation assumes a very lean car produces less emissions, but the truth is it would produce an excess of NOx, where a stoichiometric setting of 14.7:1 would theoretically be most efficient. Not in Automation!