HELP: Hondata's "stock" k24a2 tune

[chubbychu]

14.7 is good for closed loop. 13.2 - 13.5 is good for open loop. I use 13.2.

Don't put the whole map to 13.5, you'll just be wasting gas.

When is your knock occurring? Is it at throttle tip in? IE: Just when you hit the gas? If so, you can adjust the TPS ignition retard for the gear it happens in.

Did you try removing 2 degrees ignition for both cam angles?

By "removing 2 degress ignition for both cam angles", you mean...adjust the cam angle tables? (not quite confident enough to mess with that...)

Yes at Throttle Tip-in, I get a knock whether its in 4th or 5th gear, its always around 4000-5000 rpm depending on Throttle position.

thre Kal you showed up your cam angles are before high cam switch (part throttle coloms 3 ~ 7 ) are very step curve so what might be happening is under part thottle around 3500 rpm the cam angles are 8~12 degrees , then when you throttle on the cam angle has to jump to 20~30 so fast. that type of steep just should be avoided, level the cam angle or have a less incline.

what affect will leveling cam angle have? Also, is it possible for you to level it for me? I have no idea what to do about cam angles yet. I'm going to learn about it right now though. :)

[chubbychu]

No luck on CAM angle tuning. I did some runs with some cam angle changes but no success. ALTHOUGH, i DO have a fresh tune with Datalog!

I left the redline @ 4600, and surprisingly, I had to tune the 9-10th column's ignition down almost 2* lower than when I raised the redline to 6000.


Thanks for all your help guys!

Uhoh. datalog wont upload. Ill try again tomorrow. or If not too much trouble for you guys, i could email it?

[talonXracer]

Fuel trim is not operational in open loop.

Only partially true.

Long Term fuel trim is retained for open loop driving operation, Short Term is not. That is why you want absolutely the minimum to zero LTFT, or it really screws up your tuning.

I was just street tuning a typeS this morning and I double checked this, Doug from Hondata also told me the same thing.

[Jpax]

upload this and tune for A/F please

[Slip_Angle]

Only partially true.

Long Term fuel trim is retained for open loop driving operation, Short Term is not. That is why you want absolutely the minimum to zero LTFT, or it really screws up your tuning.

I was just street tuning a typeS this morning and I double checked this, Doug from Hondata also told me the same thing.

Ya, your right, I meant LTFT and should have elaborated. It's actually quite obvious since STFT is really just closed loop operation... AKA: Adjusting AF to match AFCMD...

I used Raz Dyno and Theta Dyno to do all of my cam angle tuning today on the street. It worked very well. I may start a thread about it.

[chubbychu]

upload this and tune for A/F please

holy crap! I just went out to do this!!!

i had to still decrease the ignition, but its pretty much knock free almost!

How did you know what to do with the cam timing? thats amazing!

[Slip_Angle]

upload this and tune for A/F please

PAX: What supporting mods did this k24a2 have? Also, was this a dyno tuned calibration?

Just curious. The ignition is decreased in allot of places over the stock tune. The cam angles are interesting as well but very different from the ones I developed yesterday.

[chubbychu]

PAX: What supporting mods did this k24a2 have? Also, was this a dyno tuned calibration?

Just curious. The ignition is decreased in allot of places over the stock tune. The cam angles are interesting as well but very different from the ones I developed yesterday.

It is my k24, and all I have is short Intake. Bone stock k24 with stock header/midpipe/axelback.

And the decrease in ignition was me, i street tuned out a lot of knocks by decreasing timing.

the major thing that Joe did was cam angle adjustment. and that HELPED eliminate a lot of the VTEC cross-over knocks.

[Slip_Angle]

It is my k24, and all I have is short Intake. Bone stock k24 with stock header/midpipe/axelback.

And the decrease in ignition was me, i street tuned out a lot of knocks by decreasing timing.

the major thing that Joe did was cam angle adjustment. and that HELPED eliminate a lot of the VTEC cross-over knocks.

Interesting cam angles. Joe, did you dyno these cam angles or street tune them? What mods did the K24a2 have when you did the cam angles?

I got thinking about my cam tuning and a couple of items came up. The first is I didn't bracket my angles and the second was that my mid range didn't "feel" as good as the stock k24a2 tune. So.. I went for a ride with my tune first, then the stock tune. The stock tune felt smoother through out the power band with no stepping. My tune felt weaker in the mid range but came on strong after 6K... That could just be because there was a power dip and not because it's stronger than the stock tune.. Anyways, this is all seat of the pants but I'm very interested in other people's tunes and their cam angles for similar mods on a k24a2.

Below is a pic of the high and low cams that made the most power.

[Jpax]

I would like to know how you got the VTC to advance to 50 degrees without modifying the VTC on a K24a2

the VTC limits the cam advance to 32 degrees at most on K24a2 thats why they modifiy the VTC to get a full 45 degrees of advance.

[Jpax]

well, I should correct my self, the max hondata said it will go is 27 degrees.

I used a modified VTC on the K24a2 build I did but it was only good for 45 degrees, I didn't want to push it out to 50 incase of valve to piston contact.

[Slip_Angle]

I would like to know how you got the VTC to advance to 50 degrees without modifying the VTC on a K24a2

the VTC limits the cam advance to 32 degrees at most on K24a2 thats why they modifiy the VTC to get a full 45 degrees of advance.

I'm not sure if you were talking to me but if so, I have the stock VTC gear. Theta Dyno just has those labels on the left. The actual cam degree is on the right side. 10lowcam, 20high cam etc etc...

[chubbychu]

Finally Got a chance to street tune at part throttle. The good news is all the knocks are pretty much gone.

The bad news is...all the power is gone too. haha. Maybe its a placebo but, i felt like everytime i took out some ignition I lost a little bit of power.

So anyways, I just have a quick question. On my high cam fuel map, a lot of the fuel curve lines scrunch together really close. Please observe.


Is this normal or due to unintuitive tuning on my part? I went through a bunch of other tunes and none of them come that close to each other. Please advise. Thanks!

[chubbychu]

bump for some help.