Performing Honda K24a3/AST5 6spd Conversion

Hey Paul, yes like you I will dyno-tune it. I've already melted enough pistons self-tuning over the years :D As you say, too many parameters and need to know where to look to make solid tuning decisions. Fortunately for me, the K-Tuner rep is a serious Honda fiend & local to me, and Dyno tunes. I will go to him once I have all the basics sorted out.
So are those twin stripes on the road from you as well :) ?
 
First drive :D Sounds good, no leaks.

Well....i'd certainly call that milestone # 2. Congrats again !!!

Dare i ask.....how do you like the sound of the exhaust ? Tough to tell from the video clip, but did not seem to be overly loud, and a nice tone. Most of the time seemed to be more engine mechanical noise than exhaust noise....
 
So are those twin stripes on the road from you as well :) ?

LOL - no - not yet anyway :D Brand new clutch & flywheel, so not doing any burnouts any time soon

Well....i'd certainly call that milestone # 2. Congrats again !!!

Dare i ask.....how do you like the sound of the exhaust ? Tough to tell from the video clip, but did not seem to be overly loud, and a nice tone. Most of the time seemed to be more engine mechanical noise than exhaust noise....

I was hoping you would ask - I was going to link to an earlier post of your to discuss it :) The video & sound quality is crap - really hard to separate the engine noise - that seems louder in the video than in reality.

Exhaust sounds great!!! Not loud at idle at all. Defintiely sound slike it's flowing nicely under load, however I haven't redlined it at all, nor driven on the highway to check for drone. I don't expect to hear any though. Good call on the SW muffler! I'm going to leave the resonator unless it seems to be a flow problem when we get to the dyno-tuning phase :D
 
Spent a few hours the past couple days trying to find the cause of the P1009 Cam Angle code. As soon as the code is set, the cam stays in the full retard position.

I replaced the Cam angle solenoid, and rechecked the filter screen on the side of the head. After that, I looked further in to the software. The basic setting is this one:

I set it to 24º, taking these values from the TSX base code.
VTClimits.png


Today, I found the Cam angle map, and replaced the values in that with those for the TSX:

TSXcam-Map.png


I hoped that would fix it, but it did not. What I found was that the other 25º cam angle setup found in the Accord, only had a 20º Cam Angle Limit. Since the map only goes to 20º, I figured that may be why the code is setting, so I reduced the limit to 20º, and that fixed it! Yay!

The car ran better off the line with the RSX map, which has higher values lower in the rpm & load ranges, so I will try adding some degrees back in, without exceeding the limit. I'm going to take it for tuning in a couple weeks, now it OK overall.

I've also had issues with the idle. Can't get the IACV to operate properly, so I have disabled it for the time being. The problem there is, if a code sets, the engine won't rev nicely, it stumbles & stutters off idle.
 
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Raised the CAM Angle table some. Used the K24K20hybrid map as a guide, since the fuel & ign tables come from that base. Felt stodgy with the base TSX map, definitely more responsive with this. It'll do until the dyno.

I took it out for a 5 min drive again, to get a new log with the revised values. Frustrating, cos it kept dropping out of connection. Anyway, I had a moment to get on it hard when a little BMW didin't want me to pass them, in an underpass. DAMN!!!!!! This motor SOUNDS AMAZING :D !!!!!!!

Hybrid on left, my revised map on right
Cam-Angle-K24-K20vs-IHEcam1-Compare.png
 
Decided to get the 50º Cam gear so I can wind up the advance. All the performance guys say it adds a healthly amount to the midrange. Wish I had done it when I had the motor apart, but what the hey. While I'm in wait mode, I worked on the trunk trim & routed a permanent USB cable from the trunk to the spare well.

ECU cable will be unplugged & stored next to ECU when not tuning
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Going to make a trim panel that will cover the access panels, and the side rails. Added some of the heat shielding to the SS removable panel after I took this pic

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Ordered the Marshall SCX-5051 & 5052 tach & speedo. Also the JEGS 41612 GPS Speedometer Sender to drive it. Fiat tach is nowhere close to accurate, and the Fiat Punto speedo doesn't work either :D
 
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RSX 50º gear came today, and the TracTuff (-)10º limiter - which will stop it going over 40º no matter what

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Stock gear comparison

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Back together, hopefully tomorrow I'll get it installed

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How does that work?

This is a description of VTC, if that is what you meant. The window in that gear is equal to 50º. The hardened roll pin is equal to 10º, and will prevent the gear rotating on the hub beyond 40º. Centrifugal force will place it in that corner in operation. They (TracTuff) have had them in operation for many years at this point, and determined it was unnecessary to weld the pin in place.
 
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Argh... disappointing. I really would like to figure out a way to make the stock mid-80's dash stuff work with the K20 bits.

The Punto speedo may work with the speedohealer to conditon the signal, I haven't tried it yet. The tach is so far off, I presume due to the signal coming from the ECU vs. from a coil, that I can't rely on it at all. SInce the tach has to go, I figure I will do them both just to keep the cluster balanced.
 
Installed the cam gear today. Took hours, as I really, really did not want to risk dropping the chain off the crank gear.

TDC

IMG-20200209-114442.jpg


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Remove tensioner cover, then rotate CCW, lock tensioner, rotate back to TDC marker

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Removed all the cam caps

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chain tie-wrapped on either side to prevent it dropping

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Also secured in the middle as per various videos, however this makes no sense, as with it tensioned from above, you can't get the chain off the gear :D

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Ditched the brace & center strap.

Very fiddly getting the chain off the gear, then getting the cam and gear out of the head. No pics. Transferred PND gear, torqued to 83ft/lb, reinstalled into head. Made sure dots in gears aligned with marker lines I made on chain.

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Rotated a couple revolutions and checked all markers again

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Had to redo the OP sender channel - I had made it for 1/8" NPT port, but the correct sender I have is actually M14x1.5, so I redrilled & tapped it & installed the correct sender

IMG-20200209-154101.jpg


All back together

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Cam Angle & VTC / VTEC maps

high cam

40degreeCamAngleH.PNG


Low Cam

40degreeCamAngleL.PNG


Think I may need to drop this - the 2.4L is not as rev happy as the 2.0

40degreeREVlimits.PNG
40degreeVTClimits.PNG
40degreeVTEClimits1.PNG
 
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Not much today. Cranked the motor to get oil primed. Raining & cold, so not going outside to run it.

Figuring out where to put the GPS transmitter. It's not a sealed unit, so I think I'll put it on the corner of the dash

IMG-20200210-173314.jpg


beyond that, I made a cover panel for the S2000 seat belt reels , and added velcro to the spare well cover.

IMG-20200210-173322.jpg
 
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