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I would start with a hondata map and work your way from there on a Dyno.

Just before VTEC switch, start moving the cam to where it needs to be after VTEC (needs to be all the way advanced for VTEC so start advancing) so that it doesn’t have to move 30 degrees at the VTEC engagement point.

Is this an all motor setup? Turbo? Supercharger? They all like the cams set different.

I have some notes from the hondata seminar i attended last year if you need them send me a PM.

Hope this helps a little.
 

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You need to first select the base map that best fits your setup. Tuning cam angle appears to be very straight-foward. For WOT, you will be dealing with columns 9 and 10. Set your VTEC point for around 6500 and highlight columns 9 and 10 and assign all of that area to 0 degrees. Do a dyno pull and repeat the same for 10, 20, 30, 40, and 50 degrees. You will probably make very little power with 0, 10, and 20 degrees but it is easier to see what exactly is happening with all the cam angles overlapped. So you will have 6 dyno pulls so far, one for each cam angle. Next set the VTEC point to around 3000 and do the same thing for the same cam angles. This will give you 12 dyno pulls.

Now what you must do is create a cam angle map for both VTEC settings using the 6 dyno pulls for each. This simply involves overlapping all of the dyno pulls for each VTEC point, observing which cam angles made the most power throughout the powerband. Hondata recommends using the torque curves because they are easier to use because once unscaled, they show a better resolution and it is easier to depict between the different cam angle curves. For example, lets say 30 degrees made most power from 2000-4000 and 40 degrees made the most power from 4000-6000 and 50 degrees made the most power from 6000-7000 and 30 degrees from 7000-8100. So on your cam angle table, you would assign the cam angles in accordance with rpm to create a composite cam angle map. Once you create this composite map, do a dyno pull. Then if you want, you can do what Hondata calls "bracketing" where you add 5 degrees to all angles(the 50 degree values wont change because it is already maxed out) and do a dyno run. Then subtract 5 degrees from the original map and do the same thing. Pick the best curve for your lower VTEC point. Do the exact same thing for your 6500 crossover cam angle runs.

You will now have 2 composite cam angle maps, one for a 3000 VTEC crossover and the other for 6500rpm. Make sure you "save as" all of these calibrations under recognizable names so you can keep referring back to them. Once you have created both composite maps, you need to overlap the best dyno pulls for each VTEC point on the computer and see where the torque curves cross...that will be your true VTEC point! Once you find the optimal VTEC point, I would suggest doing another 6 runs at the six noted cam angles and overlap them again to get the best curve. Then if you want, go back to bracketing and add and subtract 5 degrees to see if you can find more power. Then you can get into ignition and a/f. If something I said is incorrect or lacks clarification, please voice your concerns.
 

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Discussion Starter · #4 ·
wow - thanks Toda Pwr very informative :wink:

hybrid racing said:
Is this an all motor setup? Turbo? Supercharger? They all like the cams set different.
all motor - jdm k20a with I/H/E & mugen headgasket (.4 increase in CR) is what is planned for the set-up

thanks - Greg
 

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Damn Toda..good info...let me save up for the first 50 dyno pulls then get some air fuels done...save some more then by late 2007 I should get it right :? JK...that is alot of dyno time though to get it right. I was actually reading a post on HT about a company that put together a Kseries hatch. They were doing some dyno tuning with an A2 swap and surprised over the amount of gain they were seeing..I believe they peaked at 221whp and 161 wtq with I/H/E and K-pro. My question is, being these hefty gains are being seen when using the K-pro..is there any one thing that seems to be the target area of improvement? Are the fuel maps really fat for safety and doing a slight lean is yielding all this power? Also, I am seeing alot of dyno numbers from the A2's, such as on your site Toda. I am wondering though, what the results are with the JDM K20A? Also, Hondata as I recall, doesn't have any base tune maps for the k20A. I would assume that using a K20A2 map for the K20A surely wouldnt be the best idea given the fact the K20A has a 20hp difference. Any light on this?
 

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RC000E said:
that is alot of dyno time though to get it right.
You are looking at 1.5-2hrs max if you know what you are doing.


RC000E said:
is there any one thing that seems to be the target area of improvement? Are the fuel maps really fat for safety and doing a slight lean is yielding all this power?
Cam angle and ignition are yielding the most gains. The RSX runs very rich on the top end so leaning it out to 13.2:1 A/F ratio will help with the gains. The RSX is programmed to run on shitty gas despite the recommended premium fuel. So if you are serious about performance, you will run either 91 or 93 all the time so that is one of the basics for Hondata's reflashes/calibrations...they are able to significantly advance the ignition. I would assume the RSX stock ecu uses very limited cam angles because of emissions. By retarding cam angles, Honda can get better gas mileage which is appealing to large numbers of people.


RC000E said:
Also, I am seeing alot of dyno numbers from the A2's, such as on your site Toda. I am wondering though, what the results are with the JDM K20A? Also, Hondata as I recall, doesn't have any base tune maps for the k20A. I would assume that using a K20A2 map for the K20A surely wouldnt be the best idea given the fact the K20A has a 20hp difference. Any light on this?
Hondata has both a reflash and a k-pro calibration for the K20A. I have seen numerous dynos of K20A2's with ITR cams and IM putting down 210-220whp. A real K20A will land slightly higher because the only noted difference is a half point compression increase. Toda's N2 cams will perform better than the ITR cams.
 
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