Performing Honda K24a3/AST5 6spd Conversion

Not much done today. It's really cold (for me anyway, teens-low twenties), and the propane heater I have in the garage doesn't make much of a difference to the temp of all the metal objects I'm touching. Decided not to weld the muffler to the tailpipe, the SW muffler should be here soon, so I'll just take this back off & weld it to that. Not enough room to get a vBand on the outlet side & still have everything align.

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this one got a little hot, but no distortion.

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Besides that, I tacked the two trunk floor sections to make them one. I cut off the support bracket for the right side seat belt reel, since I don't need it. I started making a bracket for the pedal spring, just made an "L" piece & drilled it to fit on the two forward bushing bolts. Once the spring arrives I'll figure out placement, etc.

I then took the parts car carpeting to the basement & spent about an hour cleaning it with a variety of chemicals. That all went OK, however when I was hosing it off, the sump pump started making bad noises. Took the connecting drain hose off to remove it from the sump well & check the base rotor & got completely drenched in nasty drain water :D Turns out the rotor plate vents were pretty well clogged with debris. De-crusted the vents & a few new hose clamps later it was all good again.

Besides a hole from the driver's heel, this carpet is in decent overall shape. I need to use it until next summer, when I will take care of the driver's footwell panel replacement, and then install the new carpeting I bought from Henk a coupel years back. Don't want to install that now & have it contaminated with any rust particles :)
 
So this is a secondary helical torsion spring you are mounting non concentrically to the pedal shaft? This is to avoid taking the body of the pedal assembly apart again? Will this mount on the side of the tunnel?

Offsetting it like that will have it sliding along the shaft with some lost motion, mechanical advanatage and wear the spring end (and paint). Or did I miss the manner in which you intend to resolve this?
 
So this is a secondary helical torsion spring you are mounting non concentrically to the pedal shaft? This is to avoid taking the body of the pedal assembly apart again? Will this mount on the side of the tunnel?

Offsetting it like that will have it sliding along the shaft with some lost motion, mechanical advanatage and wear the spring end (and paint). Or did I miss the manner in which you intend to resolve this?

Yes, yes and bolted to the pedal bushing bracket

I understand it will likely ride on the back of the pedal arm. Not sure if I will find this a problem or not. I absolutely do not want to cut the pedal shaft to fit a spring around the bushing.

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Given all the massaging you have done on the pedal I can understand your desire to minimize and avoid having to take that apart again.

Stupid question, any way to just use a standard spring that lives in the tunnel? More choices in terms of force (ie spring choices), mounting directly to the arm at the accel. cable and then using a wire or rigid extension to connect the spring back by the shifter opening versus the very nice bracket you have for mounting the cable end? I know, likely a royal pain to get at and would require pulling the shifter plate and fish around in a limited space which already has ten lbs of isht in the two pound bag :)
 
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I had considered a standard expansion spring hooked to my bracket and the inner lever tip, however getting one in there is quite impractical - I had to fashion that hook just to be able to position the bracket - adding a spring is not a viable option, but it would have been the most direct solution for sure. Attaching a spring to anything else in the tunnel would be equally complex - I'd want the spring to be parallel so hooking it on the tunnel wall isn't really practical.
 
Stainless Works (2.5" 4"x8"x14" body chambered "Turbo") muffler arrived this morning. I had emailed them on Thursday when it didn't show as shipped (they said 2 weeks from time of order to ship), and they said they were a couple weeks behind (!) and that I might see it by New Years. I replied indicating I really wasn't happy with that outcome, and if they had indicated at the time of order that delivery could take around a month I may well have looked elsewhere. To their credit, I got a shipping notice Friday morning.

Got it welded to the I/O pipes I had made for the Magnaflow muffler, with a little adaption due to the difference in muffler dimensions.

Seem to have good clearances all around. I'll see what happens when it's operating on the road.

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Have to cut the tailpipe & add the RedTail SS tip. Not going to do that until the car is down & level so I can be sure the extension/offset is right.

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the fact that it's not level is somewhat of a bother - however, not enough to compel me to do the significant rework to align it.

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With that out of the way , I started in on all the wiring that needs to happen. Took care of all the rear deck wiring

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Next I'll probably do the relay wiring in here for the starter & bay fan, then move to the trunk for the ECU /EMS management wiring. Not really looking forward to that. Problem is I don't have a concrete plan on how best to lay it out.
 
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Next I'll do the relay wiring in here for the starter & bay fan, then move to the trunk for the ECU /EMS management wiring. Not really looking forward to that. Problem is I don't have a concrete plan on how best to lay it out.

I used spiral cable wrap temporary to determine what layout I would use. When everything was set, I taped it. It is available at Home Depot.
 
I used spiral cable wrap temporary to determine what layout I would use. When everything was set, I taped it. It is available at Home Depot.

Thanks Paul. I'll look for that for the loom.

Finally had a breakthough in terms of having a direction for the ECU, bus bars & relay box layout. Slow day at work, so I did some sketching to figure it out. Was thinking along these lines (in the left cavity, vertical strip on the right being the left frame rail):

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played around with some cardboard, and then made the aluminum version (used the neighborhood watch sign). Recessed to keep the ECU as far in the fender well as possible. Bolted to inner wheel arch and taillamp support.

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Then I figured out the support for the relay box, and the bus bars

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template:

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cut & folded, rivnuts to secure the relay box & bus bar. Pos bar will go to the right

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anchor at the base - using the bolt that also secures the exhaust hanger plate

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Now I can get on with the actual wiring, once I get back from visiting my daughter & grandchildren in Orlando.

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[QUOTE="lookforjoe, post: 336772, member: 667"
[/QUOTE]

Tidy brackets, nicely done.

I know you have done a lot of insulating for the runk. I also know that heat is an enemy of electronic devices (as well as vibration and water). Might they be safer in the "spare tire" area.

Paul
 
Tidy brackets, nicely done.
I know you have done a lot of insulating for the runk. I also know that heat is an enemy of electronic devices (as well as vibration and water). Might they be safer in the "spare tire" area.
Paul

Yes, indeed.

I don't want to jinx myself, I don't have any water ingress issues back there. Heat is a concern, however others have run it this way. Moving the setup to the spare well is not a viable option, I would have to rewire the entire engine harness. I have mulled over ways to fit an extractor fan. Have to see how it goes in action.
 
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You could bring in air from the spare tire well as there is a path over the right wheel well behind the fender as a source of semi conditioned air.

A 12v Noctua fan could blow into a duct or pull air into the trunk. Depending on which fan you choose they are nearly silent, provide good air volume and very long lived.
 
You could bring in air from the spare tire well as there is a path over the right wheel well behind the fender as a source of semi conditioned air.

A 12v Noctua fan could blow into a duct or pull air into the trunk. Depending on which fan you choose they are nearly silent, provide good air volume and very long lived.

Good thinking! I think what I would look at is setting one up as a extractor fan to remove air from the ECU area & propel it into the cavity on the same side - the area on the DS that equates to the spare well panel is open to the gas tank cavity on mine, it could just dump there, potentially. Have to see if I can funnel a section of ducting that way. Or perhaps out to the targa sail panel vent?

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You could bring in air from the spare tire well as there is a path over the right wheel well behind the fender as a source of semi conditioned air.

A 12v Noctua fan could blow into a duct or pull air into the trunk. Depending on which fan you choose they are nearly silent, provide good air volume and very long lived.

This is what I have found so far that looks promising. Not sure whether it's better to consider pushing air in over the ECU, or draw air out. Problem with drawing air out, is that it will be pulling the heated air around the ECU. Prolly better to go the other way & have air fed in...(?)

The ECU is on stand-offs, so there is an air gap there. I can drill a mesh into the support panel & figure out mounting the fan or duct behind it. Hope I never get hit in the left rear quarter :D

PWM controller

Noctua 4 wire PWM fan
 
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This is what I have found so far that looks promising. Not sure whether it's better to consider pushing air in over the ECU, or draw air out. Problem with drawing air out, is that it will be pulling the heated air around the ECU. Prolly better to go the other way & have air fed in...(?)

The ECU is on stand-offs, so there is an air gap there. I can drill a mesh into the support panel & figure out mounting the fan or duct behind it. Hope I never get hit in the left rear quarter :D

PWM controller

Noctua 4 wire PWM fan

I tend to use two fans whenever possible. One pushing and one pulling. The pusher should be either a bit lower CFM or throttled to a lower rpm using PWM or Noctua sends a resister inline that lowers the 12v to reduce the rpm. I would put a pusher fan behind the CPU to bring in cooler air from the gas tank area and push it across the high temp area above the exhaust to the puller fan which is trying to create a low pressure side. Of course if you are full of luggage back there it will be hard to create air flow.

I use Noctua fans all the time for ventilating enclosed spaces and moving air over electronics. The motors last a long time running 24/7. My current project is using 10” fans to get the cfm I need. Amazingly quiet.
 
The irony here is that the Fiat Abarth and variants, put the ECU in the engine compartment exposed to heat and elements that pass through the radiator. Most ECU's are very robust and heat today is not an issue.


TonyK.

Grimsby Ontario Canada.
 
The irony here is that the Fiat Abarth and variants, put the ECU in the engine compartment exposed to heat and elements that pass through the radiator. Most ECU's are very robust and heat today is not an issue.
TonyK.
Grimsby Ontario Canada.

Volvo puts them in the bay since the 90's, but they are set so that there is air flow in and around them. Some have eFans in the ECU case. My C30 had the ECU built into the air filter casing to draw air over the backside fins. I would say there is a reasonable amount of ongoing circulation in the engine compartment that is not present in the trunk. I'm going to add one fan, as it really seems to be a dead space in terms of any realistic airflow .
 
Worked on a few small things last couple days. Got the tires mounted & balanced on the new Rota wheels. Have to get the rear spacers remachined from 73mm to 58.1 so I can switch between the new & current wheels (new wheels are 67.1 bore ID, however I have 67.1-58.1 hubcentric rings coming)

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Cleaned up the carpet from the parts car, and added a patch for where left heel wore through. This will do until next year when I plan to fix the DS floor pan & install the new carpeting from Henk.

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Mounted the Pos bus bar, and cut the slot for the wiring to pass through to the relays and fuses

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Finished the throttle pedal return spring mod. Used a base & shaft leftover from an home electrical light fixture

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loctite on the spring shaft, silver soldered lever to base, and washer to shaft. Spring locater tab is cut from a Volvo brake hose bracket.

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Checked tension setting prior to soldering the tensioning tab


Checking new bolt length to make sure they clear the inner lever

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Installed. Feels good, not excessive tension, just enough to make sure pedal returns to rest state

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getting the floor all cleaned up ready for the carpet

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Put in M5 rivnuts to retain the front speakers I added in the front footwells, and for the AC condensate tray on the pass bulkhead, then started installing the repaired '82 carpet. I'll need to make M5 studs for the speakers and condensate tray, it's way to fiddly trying to locate the screws into the nuts through the carpeting. I was frustrated enough with the sheet metal screws that were used previously.

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Fiddly getting it around the gas pedal, I had repaired the backside where it was torn vertically with the 1/4" heat shield/sound padding foam I had bought for the bulkhead (piece of gorilla tape is covering the tear in the rub panel). Still have to tuck it behind the steering column base bezel.

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Took the diff out of the spare AWD rear end this morning & cut back the ring gear support flange with the six weld points. Cut off the bearings off. Took it to the machine shop to use the 25 ton press, but the machinist said it would be safer to cut back the flange entirely in the lathe to remove all traces of weld before pressing the ring gear off, so I left it & the new Quaife LSD with him to take care of it.

After that, I worked on the filling in the stock seat track slots in the carpeting, the speaker & condensate tray studs, the vertical "A" pillar carpet plates and the eBrake plate & cover.

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Put butyl on the AC lines at the evaporator

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I found out the likely reason why I couldn't bleed the clutch. After the last time I worked on the masters, and finished bleeding them, I reinstalled the clutch return spring (I had removed it some years ago), since it didn't seem to be of any benefit with it out. When I did so, I clearly hooked the spring loop on the wrong side of the pivot bushing. The pedal couldn't actually reach the floor. Clutch worked fine, but no way it would bleed with only 2/3 travel

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After that, I started back on the wiring in the trunk. Put eyelets on the Pos/neg cables that will feed the bus bars. Routed like this, the whole assembly can be installed/removed as needed with the cable attached.

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Painted the relay box/bus bar support, and started on the wiring to the relays. All the switching triggers (pin3, 'ground' leg) need to go to the EMS/ECU harness. Since I want to be able to unplug and remove both this and the EMS harness independently, I'm going to add a connector for all the trigger wires rather than pin them directly to the relay box.

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Painted the relay box/bus bar support, and started on the wiring to the relays. All the switching triggers (pin3, 'ground' leg) need to go to the EMS/ECU harness. Since I want to be able to unplug and remove both this and the EMS harness independently, I'm going to add a connector for all the trigger wires rather than pin them directly to the relay box.

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Excellent progress Hussein! One idea (although I'm not sure how applicable it is in your application) might be to use an intermediate connector such as a Mate-N-Lok. These are available with up to 15 pins in the larger (high current) size.

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You can even get them to mount through panels, like in your application:

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I find that by inserting an intermediate connector, it tidies up the wiring by bringing together all wires in a bundle. Moreover, it gives the ability to remove an entire component (like a relay box) without having to undo a multitude of disparate spade connectors.

Cheers,
Dom.
 
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