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Discussion Starter · #1 ·
There is a dyno comparison thread in the NA section, wanted to start one for FI too.

-K24a2 stock block (from an '05 TSX)
-Everything else is stock K20a2 including the head, intake manifold, throttle body, oil pump, etc.
-GTX3076R turbo
-1320 side winder T3 turbo manifold
-CX Racing intercooler kit for the RSX, modified to fit the EM2
-Grams Performance 1000cc injectors
-Full 3" custom exhaust with Vibrant ultra quiet resonator and Vibrant street power muffler
-44mm Tial wastegate routed into the exhaust

This is all in a '02 Civic coupe. Made 333 whp and 276 lb ft at 7.8 psi on a Mustang dyno (around 6800 and 5800 rpm respectively) . Boost was increased to ~9.4 psi making 353 whp but knock was seen. My tuner pulled what he called a good amount of timing but the knock was still there. With plans to track this car we wanted to keep boost fairly low anyways. So instead of pulling even more timing he left it at 7.8 psi. In a car that weighs around 2700 lbs with me in it, I cannot complain.

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Sure, I'll participate.
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  • K24A (JDM) block and head
  • Supertech complete valvetrain (valves, springs, locks, keepers, guides, seals)
  • Drag Cartel 2.2 Camshafts
  • RSX VTC Gear, pinned to 45'.
  • Honda OEM headgasket
  • L19 headbolts
  • Darton MID sleeves, rods, pistons, crank blueprinted/balanced
  • CP Pistons, 87MM, 10:1
  • Manly Turbo Tuff i-beam Con rods
  • K20A Oil Pump, balance shafts removed
  • Moroso Road Race oil pan

Intake / Fuel
  • GTX35R twin-scroll, 1.06AR turbo
  • TurboSmart GenV ProGate, 50mm Wastegate
  • Custom Manifold by VirtualWorks in Las Vegas (of Supra and GTR fame)
  • Custom Exhaust, built by me
  • Custom Downpipe, built by me
  • Spoon 70mm throttle body
  • RBC Intake Manifold, ported to match TB.
  • 1300CC Injector Dynamics
  • Karcepts Fuel Rail- DW350il fuel pump
  • Synapse BOV
  • Noble factory intercooler

Transmission
  • Quaife Sequential Transmission, QKE8J
  • Geartronics flatshift Gearbox Control Unit, loadcell, and display
  • Drive Shaft Shop custom length axles, CV joints, and hubs
  • Exedy Twin-Disk Clutch and flywheel (hm032sbl)
  • Clutch Master hydraulic release bearing

Supporting Stuff
  • Blox Oil filter relocation kit
  • Dry break oil line connectors
  • Dry break clutch line connector
  • Dry break fuel line connector
  • Dry break gearbox cooler connector
  • Stainless Steel AN lines for oil, fuel, and clutch throughout
  • Aluminum hardlines for turbo coolant lines
  • Front mount Setrab Oil Cooler, removed side pod oil cooler
 

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Discussion Starter · #8 ·
My tuner said the flex fuel option in Kpro did not work well in his experience. Recommended either only using 93 octane or E85 but never a mix. Anyone disagree with his statement?
 

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Arouse the DAMPFHAMMER!
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Anyone disagree with his statement?
The concept of Hondata KPro with that Flexfuel demand is using an automotive Ethanol sensor from GM with measures from 0-100 % Ethanol. So far nothing new. The translation into fuel and ignition change is done by simple linear corrections, which reflects only one condition. Exactly that which was tuned. If there is a change in e.g. IAT, which influences the vaporization amount much more then with the easy to handle pump fuel. Especially if you live in the mountains, where you find temperature differences between valley and top of the pass street of e.g. 10 °C and MAP difference of 0.15 bar these corrections can lead to an bigger correction demand in closed loop and bigger deviations in open loop WOT situations.

Other ECU's like e.g. the AEM has more options to adapt Ethanol blending correct, beginning with the lambda target vs Ethanol content and blending (linear or stepwise linear) with one or more different Ethanol content maps. The Emtron KV8 ECU offers e.g. up to 4 map layers of e.g. 0, 25 %, 50 % 75 % and 100 % Ethanol content for VE, lambda target, ign. timing and so on which are blended linearly into each other. There are different concepts available, but as baseline, any VE based system does a better adaption as just the Honda fuel injector duration stuff. Influences from MAP, IAT and engine speed are more exact pictured into real VE with different contents of Ethanol.

Finally any engine control system has a challenge to adapt different stoichiometric AFR's of fuels. Alcohol fuels are especially a challenge as the bandwidth of different molecule length and shapes is much lower and the vaporization behaviour with temperature and pressure is quite more intense as compared to pump gas which has a wide variation of molecule shapes, it is vaporizing almost to any temperature we use a car, of course not equal on any condition but much more tolerant as alcohols. The concept of fuel calculation the stock Honda ECU is using is not the best basis for the adaption, the SW adaption of Hondata was within their possibilities of the chip storage and free parameters I believe, but is definitely bounded to bigger uncertainties when conditions changes to the tuned ones.
 

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Arouse the DAMPFHAMMER!
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9,429 Posts
Made 333 whp and 276 lb ft at 7.8 psi on a Mustang dyno (around 6800 and 5800 rpm respectively) . Boost was increased to ~9.4 psi making 353 whp but knock was seen. My tuner pulled what he called a good amount of timing but the knock was still there. With plans to track this car we wanted to keep boost fairly low anyways. So instead of pulling even more timing he left it at 7.8 psi. In a car that weighs around 2700 lbs with me in it, I cannot complain.
I like the torque curve, which is pretty flat, giving the car an nice and predictable power control. Regarding knock management IAT has to be reduced if possible. Not even 10 psi on a 10:1 CR with knock issues shows the engine would support also with less exhaust residuals (turbo setup, turbo manifold, ...). If a more retarded VTC condition leads to an advanced knock margin then this would be a way to solve that knock issue. Anyway 30 mpg and that flat torque curve says at least it is a low load low speed efficient engine setup with a bunch of power when needed. This sounds great to me, especially if you think about the gear wheel and front tire loads.
 

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Arouse the DAMPFHAMMER!
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Lotus Elise K20A2
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Doctronic flex fuel allows for a variety of changes over Ethanol content incl. a low and a high cam 2D map with individual correction factors or each cell.
I also got them to introduce fuel temperature corrections to account for changes in fuel viscosity over temperature.
Now tuning this is something altogether.
From a sensor operation prospective and how the car runs, there are no real issues, neither in open nor in closed loop.
Yes, you can essentially do way more incl. changes virtually all other parameters to get that 100% match to petrol, but short of an engine test cell and full time calibration engineers for a week or two, nobody does that. Heck, most “tuner” tuned maps are not that sophisticated for a single fuel.

Stock Honda ECU uses a BARO sensor, too. In Doctronic you can enter baro fuel corrections. For the rest, we run speed density anyhow.
 

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2005 Honda Element AWD
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Hey guys. I fear judgement but here goes my latest dyno sheet. Keep in mind please I have a K24A4 with stock internals. The A4 engine is different than the A2 and had about 120whp baseline. With Merc racing TVS900 supercharger, header, exhaust, extra I am running 260whp on my Honda Element. This is on E85 and about 8 PSI. My Element is reliable and running great and I still have AC, PS, and AWD.

Audio equipment Engineering Oscilloscope Gas Technology
Tire Vehicle Motor vehicle Automotive tire Hood
 

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Arouse the DAMPFHAMMER!
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. With Merc racing TVS900 supercharger, header, exhaust, extra I am running 260whp on my Honda Element. This is on E85 and about 8 PSI.
Thanks for sharing your dyno result. This is a very nice torque curve for your application. Did you guys lower the boost 3600 rpm for mechanical load reason? What ignition timings do you run?
 

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2005 Honda Element AWD
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Thanks for sharing your dyno result. This is a very nice torque curve for your application. Did you guys lower the boost 3600 rpm for mechanical load reason? What ignition timings do you run?
My tuner did not communicate he lowered boost. I do not know anything about ignition timings. I am a Ktuner end user. So I can upload a new or old tune when ever I want via laptop. I have a both an E85 tune and a 93 tune.
 
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