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Blended Alpha-N & MAP mapping?
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Post Blended Alpha-N & MAP mapping? 
Has any thought been given to enabling mixed-mode tuning between TPS and MAP bins? Or is this something that's possible already that I've not found on the site? From what I gather, MJ is a one-or-the-other proposition. Could it be implemented to make the most of both?

I'm already in-process of implementing EDIS-8 on another project which will be controlled by a MegaSquirt II, and that project absolutely requires MAP tuning due to forced induction. I intend to leave my carbureted toy exactly that--carbureted--because I can't see spending the dyno time and money on A/F ratio tuning for something used so infrequently. The real power is in the spark advance, so doing a "spark map only" tune seems a worthwhile effort.

MAP is obviously the better route in terms actual required spark advance, but the engine in question is a bit gnarly: It's a Chrysler 340 V8, 10.5:1 compression, with Glidden-era W2 Pro Stock heads, and a 278/286 duration, .621"/.621" lift solid-roller camshaft. Induction is a ported Holley single-plane intake with an 850CFM Demon double-pump carb. I honestly don't think this thing could idle below maybe 1,100RPM with a distributor. An extremely noisy, weak vacuum signal @ idle is a given, so I'm thinking straight MAP-based tuning is out. I doubt the engine will make more than 100% VE at full throttle, but then again, you could almost chuck a cat from the plenum to the cylinder at full lift without hitting anything. My cam grinder suggested a 4,000RPM track launch and shifting between 7,500-7,800RPM. I'm guessing he gave idle quality not a moment's thought.

The car, a 1969 Plymouth Valiant, will be primarily street-driven so I'd like to get its street manners as civil as possible.

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Hi,

Thanks for the feedback. At this time we have no plans to blend those two together, but; you could use the auxiliary input channel to effectively override the ignition advance based on the value of the input. This might emulate what you need closely enough. See the installation and operation guides for how this would work.


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