Performing Honda K24a3/AST5 6spd Conversion

Great packaging work. Nicely done.

I hope it sounds and performs as good as it looks.

I hope the new engine comes together well.

Are you thinking a broken ring on the existing one?

Thank you. Broken ring is about the only thing I can think of to explain it. Compression & leak down tests didn't indicate any discrepancies, so I'm assuming an issue with the oil ring on #4 - that is the only one that has oil in the cylinder. I'll find out when I pull it apart.
 
Only had a short while to work on it today, so I focused on getting the revised exhaust cover worked out. I'm just building another tier on the one I already made, which raises the shield approx 3/4" off the muffler. For the right side mount, I just had to adjust the lower pin to raise the muffler a fraction, that made sure there is no contact on the collector when moving the exhaust around. The flex coupler allows a high degree of radial movement.

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rather than try to use 2.5" screws, I'm going to install the lower spacer, then mount the upper spacer to that, with the heat shield. Each layer will have 1/8" closed cell foam

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with the extra frame, the floor is almost level with the frame rails, so not much depth lost there.

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Put the braces back in, I need to do the center flange lips to seal the trunk off.

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Covered the access panel with 1/8" foam. It will get the trunk carpet covering, and the DEI heat shield (on the way) on the engine side

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Drilled the upper cover frame, and added the aligning M5 rivnuts to the lower frame..

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test fit the access cover again - I had to add one rivnut on the bottom left, and drill the top lip for the M6 bolt that ties into the cross brace. Have to get more 3M trim adhesive for the carpet cover

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Figuring out securing the frames

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Went with recessing the screw holes for the lower frame, since I shouldn't ever have to remove it. Carpeted the access cover also.

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Cover will go like this

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Then SS plate on top - I have to redrill it for the revised bolt pattern
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When are you going to fire it up?

Not sure. I am leaning towards getting the headers ceramic coated. I may need to run it first, just to hear what it sounds like now. Before that though, I need to remove it all & finish the end caps on the cut cross brace.
 
Finally figured out how to address the flange for the center cross brace cover. Spot welder did the trick - until I realized I could do it this way, I couldn't see a practical way to join the flange to the original panels without a mess.

Double wall is still thin enough for trunk seal to fit properly here

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I'll use the thinnest closed cell foam I can get away with on the overlap flange - so I'll try 1/16" first

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Covering the access panel with the DEI heat shield

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edged with DEI reinforced tape

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foam on the junction flanges

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making a heat shield for the torque mount / VTEC solenoids wiring

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Took the exhaust back off today so I could weld up the factory cross brace ends

Header can be removed without removing the brace insert or top cap, just the trunk cross brace has to come out

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rights side cap welded & primed

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drivers side partial cap. The inner frame here has multiple reinforcements, so I just added a cap to prevent the inner skin from flexing where the bolts are

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painted

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Put the elements back in so I could start to figure out the 'hood' pin layout

was going to do two pins, changed my mind about that - the spacing of the slats doesn't lend itself to that. 17 total, so one centered

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trunks seal aligns nicely

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heat shield on access

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lid closes with stock hook intact - slight friction against my cross bar. I'm going to leave that intact to assist in locating the cover


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drilled the hole for the release

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as seen from underneath. Now I need to make the retainer for the pin off the cross brace

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Hi Hussein,

with all those bolts you should think about using something prettier like stainless steel socket head bolts?

I want to keep them body color, or unobtrusive. I was considering those M6 countersunk head torx screws with the bevel washer that allows them to work on a flush surface. I'll add a pic later. They are not particularly visible with the trunk in place, so I'm not overly concerned with the aesthetics, in terms of having multiple heads visible on that panel.
 
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Hi Hussein,

with all those bolts you should think about using something prettier like stainless steel socket head bolts?

Thanks for the prompt - I redrilled the holes to provide the countersink chamfer needed for the new screws

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redrilled the floor skin as well - I was considering buying a new sheet of the heavier gauge SS I used here (I cut the original unintentionally) - to not have the ugly/rough weld seam, however the price of SS seems to have gone through the roof - it was quoted at over $100 for this size (12x31), vs. about $35 the last time I bought it. It's covered with carpet, so no reason besides it bothers me to know it's there 🤪

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Thanks for the prompt - I redrilled the holes to provide the countersink chamfer needed for the new screws

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redrilled the floor skin as well - I was considering buying a new sheet of the heavier gauge SS I used here (I cut the original unintentionally) - to not have the ugly/rough weld seam, however the price of SS seems to have gone through the roof - it was quoted at over $100 for this size (12x31), vs. about $35 the last time I bought it. It's covered with carpet, so no reason besides it bothers me to know it's there 🤪

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Looks much better! Great work.
 
one additional idea I was toying with is a latch pin using the stock cable, nothing complex like the factory latch which I have no room for.

sketch at bottom left

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so, I bought a inexpensive latch that looked to be appropriate overall sizing - it will be mounted in this general vicinity:

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I'll add back the ear that is used to locate the cable sleeve, higher up to align with some part of the lever. I'm probably going to drill the lever & pass the cable through it, I have sufficient cable for that. I do need to figure out the cable throw so I can either offset the mechanism (as shown), or cut down the pin, if I need the latch set further to the right. This is mean pulling the lever & lifting the corner of the cover whilst holding the lever, but that's not a big deal - I have the additional side scoop on mine that works as a great handle. Once it's lifted slightly, the lift piston takes over.
 
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