K24A4 VTEC activation point

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RABOOST
Posts: 71
Joined: Sun Oct 25, 2015 5:10 pm

K24A4 VTEC activation point

Post by RABOOST »

OK I know the cam angle of the K24A4 is maxed at 20 degree cam angle, One thing I noticed in the KTUNER software for the stock equivalent is that VTEC activation is set VERY LOW in the 2200-2700 PRM range, Is this really the factory VTEC setting???

My concern is the low oil pressure being supplied to the VTEC solenoid at this low RPM range, I have read on Hondata for s300 as a general rule to not activate VTEC on a very low RPM and also not very high RPM to avoid oil starvation and failure.

I did notice that at low 2000-2700 RPM the load has to be almost full throttle at 700-900 Mbar according to the pre set base code, but at 3500-7200 RPM its only at 263 Mbar which is pretty much idle vacuum and would be a cruising RPM almost ALL driving condition. If this is the case, does it mean that the actual VTEC solenoid is actually activated at almost all driving condition from 2200 RPM all the way to red line almost all its life??? :shock:
KTuner
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Re: K24A4 VTEC activation point

Post by KTuner »

The factory tunes are untouched. You can verify when it's active with logging.
RABOOST
Posts: 71
Joined: Sun Oct 25, 2015 5:10 pm

Re: K24A4 VTEC activation point

Post by RABOOST »

OK thanks for the reply, If I may ask how exactly do you guys extract the exact equivalent of the OEM Honda factory tune because I have always wondered how accurate these factory tune are. I specifically also want to know how you guys were able to extract and translate the ignition timing tables off the OEM tune, I particularly notice that at around 3500 RPM at -15InHG which is common speed and vacuum at freeway driving that ignition timing is only around 34-31 Degrees timing according to the KTUNER.

From my experience almost all honda engines will show around 40-45 Degrees of timing at the same vacuum and RPM on the freeway when I attach a Snap On scan tool gauge and monitor the actual ignition timing. Based on the Factory base code you provided with the software is it really only 34-31 Degrees of timing cruising???

I just want to know how you got those values, Did you drive the stock car around and log down the values using a scan gauge and then translate that to the software or you were able to extract the ACTUAL map from the Honda ECU? Thanks
KTuner
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Re: K24A4 VTEC activation point

Post by KTuner »

You wouldn't be able to rewrite the ECU without the ECU file. If you have the ECU file you have everything that's there from the factory. I'm not sure what would need clarification here.
RABOOST
Posts: 71
Joined: Sun Oct 25, 2015 5:10 pm

Re: K24A4 VTEC activation point

Post by RABOOST »

OK here is what I mean, How did you guys determine the curve of the ignition table and the values on the STOCK calibration of the 03 Accord base map.

Im not asking the step by step process but merely asking how were you able to determine 100% that at say 3500 RPM at -15 in/HG that the OEM iginition timing is exactly 31 Degrees of timing? For example: If I was to drive a brand new 2003 Accord 100% stock and If I use an OBD2 scanner, would I see exactly 31 Degrees of timing at the same load and RPM driving on the freeway??? And at full throttle I see that the cam angle on the Ktuner shows 0 degree cam angle and ignition timing from 4000-4750 RPM is 28 degrees and has a slight dip of 24 degrees at 5000-5500 RPM, would this be the same exact cam angle and ignition timing that Honda tuned the car if I was to use an OBD2 scanner gauge like Snap On scan tool?

Possible answers Im expecting are these:

1. We were able to crack the Honda ECU code and extract the actual ignition timing, cam angle, vtec etc etc thru our MAD computer skills and programming ability.
2. We drove around a 100% stock 03 Accord and logged every single possible ignition timing, vtec, fuel etc etc and translated that to the K tuner software
3. We just gave you guys a base map that we just guessed and NOT really the actual Honda ignition and fuel tables but a safe base map to use as a start up.

Those are the 3 possible answers Im expecting.

In other words, How and where did you guys get these stock OEM values from???
KTuner
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Re: K24A4 VTEC activation point

Post by KTuner »

I answered that in my previous post, so I'll try to describe it differently. We have the OEM calibration as that's the only way we'd be able to flash the ECU.
RABOOST
Posts: 71
Joined: Sun Oct 25, 2015 5:10 pm

Re: K24A4 VTEC activation point

Post by RABOOST »

OK I will take that answer, how you guys got those Information Is irrelevant to me as long as you say that those figures are the exact equivalent of the OEM Honda tune, thanks
KTuner
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Re: K24A4 VTEC activation point

Post by KTuner »

No problem.
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