Opinions/advice on my spark map for kraken/t25
#1
Opinions/advice on my spark map for kraken/t25
Was running this map for about a year with my old mkturbo setup at 10-14 psi at peak boost, I am almost finished installing my new kraken/t25 setup.
I was hoping you guys could give me some insight as to how to better the map in, especially the 4-5k rpm range as I struggled with that.
looking for where I can get away with more timing, or where its clear I've put in too much.
rev limiter is set to 6800 currently
-kraken manifold
- garret 2554
-2.5-3in straight pipe
-flowforce injectors
any advice or criticism is welcome
I was hoping you guys could give me some insight as to how to better the map in, especially the 4-5k rpm range as I struggled with that.
looking for where I can get away with more timing, or where its clear I've put in too much.
rev limiter is set to 6800 currently
-kraken manifold
- garret 2554
-2.5-3in straight pipe
-flowforce injectors
any advice or criticism is welcome
#2
Cpt. Slow
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Well at 10-14psi you’re mostly in the 183 and 212 row, or ~17* in boost. I wouldn’t think you should go much more aggressive with timing until
you visit a dyno. You’ve been smart with reducing your spark 2-3 degrees per psi, however if you over boost into the 18psi range, that’s the one place you haven’t done it.
you visit a dyno. You’ve been smart with reducing your spark 2-3 degrees per psi, however if you over boost into the 18psi range, that’s the one place you haven’t done it.
#6
Cpt. Slow
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I too was going to mention the 100kpa row for naturally aspirated cars is usually in the ~28* range, but you'll almost never be in that row without being in boost. It does dictate your boosted ignition values if you apply a 1*/psi theory to 28 vs. 26.
#8
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Yes, that's what he means.
I think that rule of thumb for increasing timing as manifold pressure increases might be perilous for some noobs who may read this in the future. There are differences in how much you can add per unit of pressure increase relating to the compression ratio of your pistons and your AFR targets. A car running 8.4 or 8.6 to 1 versus the car running 9.5 or 10 to 1 will have very different timing values in positive pressure. And the car running excessively rich will have different timing values from one running stoichiometric or versus lean fueling. Same thing with 93 octane versus parts of the country limited to 91. Or 1.6 versus 1.8 engines.
Having a rough idea is fine. Just be careful to pay attention to the sources and ensure they are similar to your own.
I think that rule of thumb for increasing timing as manifold pressure increases might be perilous for some noobs who may read this in the future. There are differences in how much you can add per unit of pressure increase relating to the compression ratio of your pistons and your AFR targets. A car running 8.4 or 8.6 to 1 versus the car running 9.5 or 10 to 1 will have very different timing values in positive pressure. And the car running excessively rich will have different timing values from one running stoichiometric or versus lean fueling. Same thing with 93 octane versus parts of the country limited to 91. Or 1.6 versus 1.8 engines.
Having a rough idea is fine. Just be careful to pay attention to the sources and ensure they are similar to your own.
#10
Cpt. Slow
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Remember; I wouldn't advance your table without dyno or knock tuning.
I find naturally aspirated engines make max power at around 28* at red line. For turbo cars, I take about 2* off that, then then at ~2.5 psi take 3-4 degrees off, and from then 1 degree per psi, which with rows at roughly 2.5 psi apart in most base maps, are 2 or 3 degrees less every row, with dyno tuning to confirm it works.
I find naturally aspirated engines make max power at around 28* at red line. For turbo cars, I take about 2* off that, then then at ~2.5 psi take 3-4 degrees off, and from then 1 degree per psi, which with rows at roughly 2.5 psi apart in most base maps, are 2 or 3 degrees less every row, with dyno tuning to confirm it works.
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