kefi
oh shit waddup its dat boi
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THIS ANALYSIS HAS BEEN REDONE, CLICK HERE
There's a lot of people wondering 'does this basemap work for me if I have X and Y but not Z', including myself, so I went and compared the major US FK8 basemaps from Hondata to see exactly what they changed so I can better understand what these parts are needing.
I've found that it's mostly incremental, the majority of changes are in the base 91 octane tune.
91 octane vs stock (+34hp/+39tq)
Catless downpipe: ~5% lower aircharge and various changes to intake/exhaust cams.
High flow cat downpipe: advance ignition by 2.25 degrees >= 130 air charge
Downpipe with intercooler: advance ignition by 0.75-1.50 degrees >= 130 air charge, increase air charge limit ~5%
Note that this is presented as a tree.
93 octane: advance ignition by 2.25 degrees >= 130 air charge, with 0.75-1.50 degrees additional advance over 4500rpm/190 airC, netting +14hp/33tq
So, things to take away from this:
I was hoping maybe someone else could expand on *why* those cam changes are made for the downpipe and why they're subsequently removed once an intercooler is put on.
There's also some weirdness in the 91 octane tunes, i.e. how there's no ignition advance for a catless downpipe but there is for a high flow cat, and how the high flow cat tune has more overall advance than the downpipe+intercooler tune.
I'm also not sure whether the downpipe+intercooler tunes are meant to be high flow, catless, or both.
There's a lot of people wondering 'does this basemap work for me if I have X and Y but not Z', including myself, so I went and compared the major US FK8 basemaps from Hondata to see exactly what they changed so I can better understand what these parts are needing.
I've found that it's mostly incremental, the majority of changes are in the base 91 octane tune.
91 octane vs stock (+34hp/+39tq)
- Increased torque request in sport/R maps in 3rd-6th gear >= 69% TPS. Max 480 from 425 stock. Also notably, at 100% TPS torque request will be 480 regardless of RPM, unlike stock where it will ramp up at lower RPMs.
- Torque limiting tables set to 600 across the board, from stock values 358-481. Essentially made to not be used unless something goes really wrong. I believe Hondata posted somewhere saying using this table to limit torque can be choppy.
- +0.75 degree advance to all non-VTEC ignition maps (i.e. during spool)
- Boost cut increased from 2.86 to 4 (this appears only in the compare window, it's part of the increased limits mod rather than a value you can set yourself)
- Turbo max ratio (PA) rescaled, max from 3.03 to 3.7
- Turbo max ratio (temp) rescaled, max from 3.6 to 3.9
- Air charge limits set to 245-200 (stock values appear to be placeholders, no stock aircharge limit?)
- VTEC intake cam 6500-7000rpm increase by 4 to 6 degrees
- Spool intake cam increase by 5 degrees across the board
- Minimum lambda rescaled to mostly 14.7, minimum from 10.29 stock to 11.47
- Target lambda is almost exactly the same except slightly leaner at max airC/RPM
- Knock retard step reduced by 0.75 degrees in some spots
Catless downpipe: ~5% lower aircharge and various changes to intake/exhaust cams.
High flow cat downpipe: advance ignition by 2.25 degrees >= 130 air charge
Downpipe with intercooler: advance ignition by 0.75-1.50 degrees >= 130 air charge, increase air charge limit ~5%
Note that this is presented as a tree.
93 octane: advance ignition by 2.25 degrees >= 130 air charge, with 0.75-1.50 degrees additional advance over 4500rpm/190 airC, netting +14hp/33tq
Downpipe: ~5% lower aircharge and various changes to intake/exhaust cams.
Downpipe with intercooler: advance ignition by 2.25 degrees >= 170 air charge, increase air charge limit ~5%
PRL downpipe/PRL intercooler: reduce IAT2 ratio compensation by 50%, increase PA/temp max ratio by 0.5, reduce knock retard step by 0.75 degrees
100 octane: advance ignition by 1.50 degrees >= 130 air charge, increase torque request to 504, reduce knock retard step by 0.75 degrees, increase max turbo ratio by 1, +26hp/15tq over 93 octane
So, things to take away from this:
- The base 91 octane map barely changes ignition from stock and doesn't at all under VTEC. It gains power through more boost, better spooling through slight cam changes, and much safer AFRs (stock can go as low as 10.29!).
- Adding a downpipe by itself commands a lower cylinder filling (air charge) and has cam changes to help (I think) with spooling. There's no change to ignition or boost limits in either 91 or 93 octane.
- On 91 octane, you get more ignition advance with a high flow cat than with the catless downpipe+intercooler tune, but no ignition advance at all with the catless downpipe tune?
- Upgrading to 93 octane nets you +14hp/33tq simply by advancing ignition by 2.25 degrees at 130% aircharge and above, with a little more at the top. Nothing else is changed.
- Downpipe w/ intercooler adds 0.75-1.50 degrees more advance with 93 octane than with 91 octane.
- The 93 octane downpipe+intercooler tune doubles the ignition advance from 91 to 93 octane above 170% aircharge. However, the downpipe cam changes are reverted and air charge is now higher instead of lower.
- The PRL tune slightly raises the boost ratio limits, and reduces the effect of high (40-60C) IAT2s. This is major in climates like Florida. It also slightly reduces knock retard.
- The 100 octane tune of course advances ignition, but not as much, relying more on increasing boost.
- Every ignition change Hondata's tuner makes (with the exception of the base 91 octane only advancing the non-VTEC maps) is across all ignition maps equally. They also recommend you do this in their tuning guide.
I was hoping maybe someone else could expand on *why* those cam changes are made for the downpipe and why they're subsequently removed once an intercooler is put on.
There's also some weirdness in the 91 octane tunes, i.e. how there's no ignition advance for a catless downpipe but there is for a high flow cat, and how the high flow cat tune has more overall advance than the downpipe+intercooler tune.
I'm also not sure whether the downpipe+intercooler tunes are meant to be high flow, catless, or both.
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