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hondata/kpro k20a2 fixed angle cam map tuning on the road?

Road Tuning

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so i went through the road tuning course but also came across an article in regards to tuning on hondatas kpro, they talk about tuning fixed angle cam maps on a dyno, is this neccessary and or possible to do on the road? heres the copied piece from the article..

3.2.1 Dynotuning fixed angle cam maps

You need to create a total of twelve test maps, six each for the low-speed cam and six each for the high-speed cam. In each of those sets of six, the first has ALL angles set to zero, the second ALL angles to 10, and so on to the final map that has all angles set to 50. You then go on the dyno and do runs for all twelve maps. In order to do separate runs for the low-speed cam and the high-speed cam, you need to set the VTEC point to 6500-7000 first (for the low speed runs) and then to perhaps 3000 for the high speed runs. That way, the engine will stay on one cam for the entire rpm range that matters. For each procedure, set both the high speed and the low speed cams at the same fixed angle.

Start with the first fixed cam angle map and optimize it first for proper air-fuel ratio and then for ideal ignition advance. That requires considerable time and expertise, especially since the K-Pro doesn't have that handy target lambda feature of the s200 series (yet?). However, it is not too difficult to arrive at a proper air-fuel ratio by adding and removing fuel across rpm ranges. For ignition timing, you can create a map from scratch if you are a true expert, or use the ignition maps from a similar calibration if you're still learning. Determine best power by advancing ignition by two degrees at a time until engine power no longer increases or the engine starts knocking. It is generally advised, in the interest of engine longevity, to stay about two degrees shy of maximum power.

After quite a few dyno runs you end up with an engine that is optimally tuned for each angle at each speed AT A STEADY ANGLE, and you have twelve dyno maps.

You may wonder why you should spend a lot of time tuning the 0 degree cam angle map since it doesn't make much power and is rarely used in regular driving. In fact, the 0 degree cam is important because that is where the engine is at when it is first started. The cam stays locked at zero degrees for ten seconds, and it's important that it is set properly. In addition, in limp mode the engine reverts to, and stays at, zero degrees, so there again we need a well-tuned zero degree cam angle map."

Tuning any continuously variable cam timing map accurately on the road unfortunately is difficult or impossible. To tune cam timing properly you need to see how the torque is changing as you alter the cam angle and this requires a dyno.

You can still get some clues as to when you're moving in the right direction on the road though - For example when your cam timing change is going in the right direction, the VE of the engine will improve and hence for the same injector pulse width, the lambda will move lean. This is a guide but the differences become too subtle to be able to base tuning decisions off this alone.

If you're limited to using the road, your only real option is to use one of the base maps for cam timing and accept the fact that you may be giving away some power/torque.

thanks for the answer, hondata had a video about it aswell that helped understand your answer.

i ended up going with a base map, switched up the injectors from 450 to 1000 and set the deadtimes, car runs lean at idle so i bumped injectors down to 850 and noticed it perfectly around 14.7.. weird, any idea why? also noticed when first turning the engine on the af would read anywhere between 15-18:1 for a few seconds and then find its way back down around 14.7. any advice there would be appreciated. wish my computer wasnt giving me trouble i cant get it to read any sensors so im working with my phone and ecu being connected and watching the sensors on it.. not sure if its a good idea to try and datalog until i can get it resolved. any one know why my computer wont provide sensor feedback? even though my phone does?

on the bright side i got my af idle decent :)

thanks for the help so far, road tuning course is good stuff

If you are running 1000 injectors then there is no reason why you should put in 850. When swapping in different injectors its normal that your map might need some fine tuning some injectors just work and some brands need more work. Lean at startup could be from improper tune or not enough cold ect enrichment.

How do I mess with cold ect enrichment?

What do you recommend to try? I'm thinking to Switch back to 1000 and add fuel throughout the map?

I guess I need to check everything my fuel pressure is at 50 and my dead times are set to correspond 60psi with the vacuum line connected, is this the right way or should I disconnect the vacuum and then set fuel pressure... Keep in mind I'm using a base map from kpro "rev hard turbo, 440cc"

Thanks

The fuel pressure should be set with the vacuum line DISCONNECTED from the fpr.

ECT TRIM (engine coolant temperature trim) Go to Parameters > Fuel Compensation > Water Temperature Compensation

You should first tune your fuel map and ignition before messing with the cold start though.

Ok thanks, so since I'm going from 440 to 1000cc injectors what should I roughly look to do? Add fuel to the tables or subtract?

I'd suggest starting with the correct injector parameters and then addressing the fuel tables as required - ie if the engine seems lean everywhere then you can start by applying an across the board trim to all the fuel tables to get you close before beginning to fine tune them.

Hey just a thought for a similar issue that I had, which is deciding on cam timing for a Toyota VVTI engine.

Does your engine have an airflow meter / MAF sensor hooked up?

I datalogged the output of the MAF sensor, and did RPM pulls at 0 degrees advance, 10 degrees advance, etc.

Then put the info into a graph like this

My thoughts are that whatever settings cause the highest amount of airflow through the MAF sensor, must mean the most air getting stuffed into the motor which = more power.

This method is a lot more precise than monitoring lambda values.

Hey David, unfortunately the K series engines are speed density only so they don't include a MAF sensor.

That being said, your idea is quite clever. I'm going to see how that pans out on the dyno with our 350Z and 86 and see how it works out. Thanks for the idea!

awesome, would love to hear how it turns out.

someone gave me some suggested angles from dyno results before I started, and I also had some literature from Toyota.

But I wanted to see how well the MAF idea matched up, and it was pretty much bang on.

I think the areas that were slightly different were on account of different intake and exhaust combo working to different RPM ranges, so MAF data still seemed better than someone elses dyno results which came from a different configuration.

while looking for info initially, one of the most interesting articles I came across was actually some comprehensive dyno testing done on a K20A, might be a good read for original poster of this thread

http://www.superstreetonline.com/how-to/engine/0510ht-fuel-economy-tuning/

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