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I'll be looking to get a dyno tune done. But, to get it around, I thought I could utilize a base map of the Z06 that had higher compression and remove 2 degrees.
My engine is a 5.3L.
Overbored 0.30 to 3.81.
head was decked down .004
stock stroke
Heads are 58cc combustion PRC 2.5 5.3L heads
Cam is TSP 228R 112 LSA
Pistons are summit pro ls 2cc dome, with valve reliefs.
Eagle H-beam rods
My rough calcs.... Compression should be ~11.3:1. Dynamic, I think... should be near 8.25:1? Couldn't find solid # on 228R IVC.
My question is... if I take the Z06 map I found, tried to go from MAF to my speed density, and removed 2 degrees everywhere... do you think this is okay for the given compression ratio until I can get dyno time? My area, all dyno tuning is out about 3 months.
I'll be running 92 Octane, which is highest available in my area.
In this map, I don't fully understand why the ignition areas aren't 'smooth'. Stock map is like that, and I thought maybe it had to do with resonance, or something I don't fully understand. Is 24 degrees at 2600-3200 too much for compression ratio?
Speadsheet I used below. Notched head gasket from Mahle looked like compressed is .051.
Which part is different? I know the HP Tuners map is inverse, or appears inverted. Like, increased air towards the bottom, where mine is speed density, so more air is on the top of chart.
Timing on .72g/cylinder and up, is same timing throughout the RPM range.
.2g/cylinder and below is almost identical timing throughout the range as well.
So, I took between those values, and set .72g/cyl as my upper limit (100kPa) and .2 g/cyl as my lower limit (30 kPa).
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Base timing for new engine build 
