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Tuning Ignition timing map

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When we are adding Ignition timing on the timing map, does it make any difference if we focus only adding 5k to 7k range and leave 3 to 5k alone will we less likely to encounter knock this way instead of adding overall from 3k to 7k range?

I understand we still need to keep timing curve smooth and adjacent cells within 2 to 3 degrees, just i was always tuning entire 2500 to 7k boost section together never really tried adding timing just on top end and see if that actually works better to achieve more whp on pump gas.

This is dealt with in our practical tuning courses in some detail, however to elaborate I would start by adding timing to the entire WOT range the engine is operating in and checking the results. I'd normally do this in 2 degree increments and any time you see no change in power, or a minimal improvement then I'd take that timing back out. This lets you tune quickly towards MBT or the knock limit depending which comes first.

Unless you are knock limited which is quite likely on pump gas, or you're concerned about engine strength and hence you're purposely limiting low-mid rpm torque, there's no real reason to not tune the low rpm range of your timing map the same way you'd do the high rpm region.

I find Subaru very likely to knock with TMIC and high ambient heat on pump gas this is why i've been thinking and trying ways to still make the car some what enjoyable but much less likely to knock.

I have used IAT ignition compensation to combat high heat situtation but people are telling me car feels so slow in 90 degree weather, so i am just trying to figure out any possible tuning technique to get them still enjoy the tune.

It's a real issue with the TMIC and there are two things that combine to make life more difficult for the tuner. While at highway speed the TMIC does a pretty good job, around town and in stop start traffic the TMIC acts more like a chimney and this will result in the TMIC heat soaking. On earlier cars without the benefit of a manifold air temp sensor, the air temp was being measured in the MAF sensor which was not specifically relevant to the actual charge temperature, hence making it impossible to apply an effective trim to the ignition timing.

My technique for dealing with this in a standalone is to retard high load timing at high MAT values and at the same time reduce the boost target under those same situations. This protects the engine when the driver goes to full throttle after the TMIC has heat soaked. Once the MAT drops to normal temperatures, the timing and boost will be restored. You're a little more limited however with the OE ECU as to exactly how much control you have over ignition trims and boost targets.

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