Performing Honda K24a3/AST5 6spd Conversion

Turned out the flex coupler had not broken, not in the sense I was expecting anyway. The end collar separated from the lining. Perhaps my delicate (for once) weld on that seam was the problem - didn't penetrate to the inner material. So, I pressed it back on & welded it on the inner lip seam.
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While I was on the exhaust I cut back the tailpipe and welded the RedTail exhaust tip on

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Finished up the remote adjuster for the balance bar.

Made a bracket for the adjuster knob, and a reinforcing plate for the backside of the dash. Threaded the knob plate for M4x.75 screws

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Bracket installed, cable cut and braised to prevent unwinding. Routed the cable over here to keep potential cable kinks to a minimum. I considered putting it under the driver's side, but it would be in the way. On the inboard side of the PS, it would be in the way of removing the fusebox, so it is what it is. Shouldn't need to be adjusting it while driving anyway.

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Worked on fitting a bluetooth stereo in the glovebox. I also considered removing the center vents & putting the stero there, but then I'd have to figure out where to put them...

Cut up the spare glovebox insert from the parts car. Made an aluminum insert to retain the unit.

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Test fitting for air duct clearance, since I had to chop off the top of the insert

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I had to push the firewall out to get my AM/FM/Cassette to fit in 1974. Radios were much bigger then plus the early style dashboard sat behind that shelf leaving even less room than the later dashboards.
 
Washed the car yesterday for the first time since I started the k24 work

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Interior mostly back together

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swapped out the ambient temp gauge for one that is more legible in sunlight

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switched to ºF

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I want that box. Well, not the box but what is in it. I imagine you have lots of boxes of wonderful things just like that in your garage.

You can get your own on Amazon :) I typically buy connectors & terminals from Mouser, however these are actually nicely made housings. The connectors are plain brass, so I wouldn't use them in place of quality tinned versions for mission-critical installs. No way you can beat the price just for the connector housings.
 
Bunch of things. 100 miles or so on motor now.

AC lines have to be reworked. As it stands the cover hinge is hacksawing the lines. No availability of 90º extended fittings for the lines, so I need to modify the 90º hard elbow at the compressor. I bought #8 & #10 straight MIOR steel fittings, which I will cut down & weld/silver solder to the elbows to extend the connection 2-3" outward, which will allow me to lower the lines relative to the hinge, and closer to the bulkhead.

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Problem: Both left & right side outer CV bolts backed out(!) couldn't walk due to CV boot interference. Cleaned up the CV grease spray & retorqued to 31ft/lb. No way to remove the bolts to clean for loctite, for example. That explains the click I heard the last 20-30 miles when pulling away in 1st

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I also notice that there is seepage around the left CV where it seats in the Diff casing :( I'll have to order another seal for that.

Installed the OEM OP sender from MWB, all good now - gauge reads as it should

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While I was there, I noticed some oil spray on the oil cooler hoses, and around the OP idiot sender. So, I cleaned it all up & rechecked the extension fitting, adaptor line for OP gauge sender, and OP idiot sender - that did take another 1/2 turn or so, so hopefully that's done with.

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After that I re-wired the AEM WBO2 harness to accept the newer LSU4.9 sensor. The gauge wiring is the same, so only need to modify the sensor end

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Gauge end is compatible as is

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Swapped out the gauge / controller, and the new one is dead. Have to return it & get another. No practical way to get just the controller quickly, so this means buying another kit, swapping out the controller & then returning the kit as defective.

Hopefully not too much more in the way of teething pains.

I do still have to resolve the fact that the IACV circuit does not work at all. I had to add a manual bypass valve to allow me to raise idle when cold, then close once it has run a few minutes. This **** ain't gonna fly long term, as the engine likes to stall on deceleration, sometimes :(
 
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Bunch of things. 100 miles or so on motor now.
do still have to resolve the fact that the IACV circuit does not work at all. I had to add a manual bypass valve to allow me to raise idle when cold, then close once it has run a few minutes. This **** ain't gonna fly long term, as the engine likes to stall on deceleration, sometimes :(

My IACV uses the MAP sensor to trigger it. Is yours functional and accurate?

My system is a Bosch unit that I can feel actuate if I am touching it, I do not know the Honda system, but it might be a source of information for you in trouble shooting if it is in the valve or the engine management system.

Paul
 
My IACV uses the MAP sensor to trigger it. Is yours functional and accurate?

My system is a Bosch unit that I can feel actuate if I am touching it, I do not know the Honda system, but it might be a source of information for you in trouble shooting if it is in the valve or the engine management system.

Paul

Thanks for the input Paul. I will need to find the Honda Design/Function manual to understand how it is controlled. I know the circuit is good, as in power ground & signal. The Honda unit is a bootleg little thing not like a Bosch part :D
 
Oil leak on back of motor is coming from the VTC oil control valve on the cylinder head. Don' recall if I had had that off the head when I redid the block. Anyway, new seal is ordered.

Small exhaust leak around the 3" VBand securing the "J" pipe with the flex section to the header. Have to address that.

Spent some time checking the IACV - the circuit wiring and signals are definitely correct, one of the two I have is NG, has 10v on the signal terminal, the other has under 2v.

Regardless, the motor will not idle under 2K rpm unless I block off the bleed port in the TB outer. I installed the KTuner user board in the RSX ECU (37820-PND-A63), following the eloraborate reset/unlock procedure (which has to be done with internet access, and my driveway is on the outskirts of my home network reception, of course). I was kinda hoping the issue was ECU related, but no such luck.

Beyond that, the ECU is somehow now locked, so I can't access the logging or editing features of the tune I uploaded to it - it never ends :D

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I use the Hotspot feature on my phone to get Internet access in marginal coverage areas. It works fine as long as the phone has a signal.
 
I use the Hotspot feature on my phone to get Internet access in marginal coverage areas. It works fine as long as the phone has a signal.

That used to work for me when I had an iPhone - with my Google FI Pixel3a, it shows up, and I enter the password, but it never connects :(
 
To get the ECU to work, I have to reinstall the old ECU & unlock it again, making sure the internet access is present, then swap it back & redo the locking process, making sure again that internet connection stays active :(

AC line fittings came - so hopefully tomorrow I'll get those in

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You might consider moving your WAP out to the edge of the house or to the garage for the event by buying a Ethernet cable or even getting a cheap wireless router that could live permanently in the garage or in the house nearest the garage. A 50-100 foot ethernet cable is pretty cheap as are some of the older generation wireless routers etc. CAT5E has a 250’ max length to maintain speed/reliability of packets if you want to go direct to the the laptop (wires are the most reliable). Just a thought.

Frustrating how the process needs to work to bless the ECU. Good luck with it.
 
Going back a few pages, Performing Honda K24a3/AST5 6spd Conversion a couple of questions about the AC lines, can they be rotated counterclockwise at the compressor to move them down and closer to the compressor? Or as suggested in the post from the past, can you make a steel cover to go over the lines that is attached to the compressor to serve as an unyielding barrier to the hinge?
 
You might consider moving your WAP out to the edge of the house or to the garage for the event by buying a Ethernet cable or even getting a cheap wireless router that could live permanently in the garage or in the house nearest the garage. A 50-100 foot ethernet cable is pretty cheap as are some of the older generation wireless routers etc. CAT5E has a 250’ max length to maintain speed/reliability of packets if you want to go direct to the the laptop (wires are the most reliable). Just a thought.

Frustrating how the process needs to work to bless the ECU. Good luck with it.

Going back a few pages, Performing Honda K24a3/AST5 6spd Conversion a couple of questions about the AC lines, can they be rotated counterclockwise at the compressor to move them down and closer to the compressor? Or as suggested in the post from the past, can you make a steel cover to go over the lines that is attached to the compressor to serve as an unyielding barrier to the hinge?


Thanks for the input Karl.

Our current WIFI is part of our cable service, and is now integrated into the DVR box - it used to be the router was a separate component. I will have to investigate ways to extend the range. I think it will be easier for right now if I just roll the car into the street & park illegally in front of my house for the 1 hour I need to complete the reinstall/unlock, remove/transfer/relock procedure :D

With the AC, the lines cannot be moved in any way besides upward as it currently sits, the compressor brackets/mounts are directly below the hoses as they are now. The hinge is not level as it is, so it will only be worse once the cover is on. It's not that big a deal to cut & weld the fittings, and I think it will be cleaner with the lines further out - there will be more allowance for movement with the drivetrain that way also.

My biggest frustration (besides redoing small ****) is the idle. The problem is, the situation extends into drivability at part throttle - response can get jerky, causing it to buck & just generally twitchy throttle feel, besides the random stall on coming to a stop situation. No way I'm driving any distances with the car without this being resolved completely. The car feels great on the highway - very fast & quick acceleration - a little too easy to get up around 100, so I will have to be very careful once I am driving it routinely. A young fellow in a modded Lexus 2 dr was filming me on the highway, coming up on either side & doing little speed spurts - I guess he was trying to figure out what kind of Honda came with a mid-engine setup :D
 
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