Honda L13A Engine Swap in HA12 ALTO

[OwaisYunus1]

Assalamulaikum all. I hope you are all doing well. I haven’t posted at Pakwheels for a long time so I’m here with another project.

The car in question is a 2002 HA12 Alto. It’s a PKDM variant which originally came with an F10A engine. The engine was a little over 300,000km driven but it was still running strong. I was getting around 14km/l within city (I know it’s unbelievable for this engine but a combination of keeping it well-maintained, different jets in the carburetor and light foot driving helped achieve this.)

The idea behind this swap was to improve the fuel average of the vehicle with the insane fuel prices these days and to convert the transmission to auto. If I could get better performance, that would also be a plus. Now I could go the safe route of a K6 auto swap to get better fuel average but that wouldn’t have cut it because of the lack of power. I could use a K6 turbo instead but that wouldn’t help me achieve the fuel average figure that I was after.

Therefore, with limited options to achieve what I wanted, I decided to swap in a Honda L-13A IDSi with a CVT transmission into it. Why an L-13A I hear you ask? a) It is known to have good fuel average, even in heavier cars such as the Honda City, Civic and the Honda Jazz/Fit, b) It would have a CVT Transmission, therefore helping achieve the auto transmission bit and c) with 85hp and about 120nm torque, it would offer good power to weight ratio in a car that weighs a little shy of 700kg.

I have an ongoing series of Videos for this project on my channel, you may visit the channel at,
www.youtube.com/@funcariauto/

Here are some specifications of the engine.

Engine Code: L13A
Engine Capacity: 1339cc (Offered in the 1.4 Honda Jazz GG/Fit GE, 1.4 Honda Civic FD)
No. of Cylinders: 4
IDSi – Intelligent Dual Sequential Ignition, which means there are Two Plugs per cylinder, sequentially fired for better efficiency.
Power: 85hp @5700RPM / 120nm Torque @2800RPM
Compression Ratio: 10.8:1
7 Speed CVT-Transmission (SWRA)

Most of the work on it is done in-house, which includes mechanical, fabrication, electrical and aesthetic. So let’s begin the process.

The car, just before going under the knife.

On jack stands and dismantling started.

The engine bay before the swap.

[OwaisYunus1]

The old engine, the F10A coming out.

[OwaisYunus1]

The engine is out and the engine bay thoroughly cleaned before doing anything else. The battery of the car leaked at some point in time which damaged the paint on the left chassis leg. Good thing that it was only surface rust which was cleaned and then painted later. Other than that, there was no damage at all in the entire engine bay, rust or whatever.

[OwaisYunus1]

I was able to source a dummy Honda L13A engine with a CVT transmission for a mock fit. Getting a dummy engine was important at this stage to check if its actually going to fit the engine bay or not. Had I gotten the actual engine, and it wouldn't have fit, it would've been a waste.

[OwaisYunus1]

The engine being hoisted into the engine bay for a test fit. It fits!

Its a very tight fit but it clears all the essential components in the engine bay, so its good news here.

Here, you'll notice that the brake master cylinder is very close to the oil filler cap on the valve cover. There's about half an inch of clearance on both dimensions. However, a different servo + master cylinder will be used to properly clear the engine, while retaining proper functionality.

[OwaisYunus1]

Cardboard templates made for the side mount brackets. Cardboard is used here because its easier to work with carboard in the design phase than with metal so that any changes needed can be done easily.

The transmission side mount is going to be a rather complex design. The reason for that is, the mount is offset from the mounting points on the transmission. If I had used a simple plate from the mount to the transmission, it would have served as a lever, which would keep the rubber bush in the mount in a twisted state at all times, because the engine would want to lean down from the back, as that's where the weight of the engine engine/transmission is.

What I've done with this bracket is, first, I've used the timing side mount from a Liana, as it was a lot beefier than the original alto one. Then I've placed a plate on top of it and made arms on it in a way that about half of the weight of the transmission is pulling on one side of the mount, while the other half is pulling on the other side of the mount. This essentially somewhat cancels out the lever effect that a straight plate would have and evenly distributes the weight on this mount.

This also ensures that the weight of the engine is on the side mounts and the bottom mount is not bearing any weight. When designing mounts, it is important to design them in a way that the side mounts are the load bearing ones, and not the bottom mount(s). If the weight of the engine is borne by the bottom mount, it will get damaged prematurely, and would affect the feel of the vehicle as there will be constant engine vibration in the chassis.

The templates are made in 5mm thick cardboard to avoid errors once the pieces are transferred to metal because 5mm thick MS plate shall be used for those.

[OwaisYunus1]

Once the cardboard templates for the side mounts were done, they were converted to digital templates and then handed over to the CNC shop to cut the parts in 5mm thick Mild Steel plate. The CNC was a laser type and not the plasma type, hence the clean and accurate cuts.

[OwaisYunus1]

So out came the welder and the parts were first tack welded around the engine and then taken off to properly weld them. Once they were welded, the engine was attached to the chassis with the newly made brackets to test if they're taking the load of the engine the way I intended them to. Gladly, the engine sat perfectly straight, without leaning back. I'll let the engine sit for a couple of days so that the side mounts may settle and then the bottom mount can be made accurately.

For the timing side mount, I used the same casing of the mount as the original Alto one, but replaced the rubber insert with a beefier one. Here, I thought ahead and kept the distance between the eyes wider than the current mount incase this mount didnt work, I would have space to insert a wider mount.

The engine, hanging on the side mounts for the first time

[OwaisYunus1]

Welding, grinding and then some more welding.

And then there was paint.

[OwaisYunus1]

This is it for now, I'll be sharing more progress later.

[shockxwave]

Woah! Super excited man. I've been thinking of doing something like this at home for a long time now and want to make a proper YouTube series about it. Love to see someone doing this kind of work at home DIY. I've been doing all of the maintenance work at home myself lately but still haven't been able to make a proper set of tools (student life) 🥲. Anyways, love the way you've been carrying out the work. Can you tell us a little about your tool setup and that awesome lift? Also what do you do for a living if you don't mind me asking?

[Hassan1991]

[Hassan1991]

Good going. Keep us updated.

[nfsmostwanted]

Beautiful beautiful project!

Something really great !
Keep the pictures coming, lots of them

[Mun33b]

This is some good stuff. Subscribed, love the cleanliness. Although I am not a fan of doing such mods to these poorly built cars, but it seems like you know what you are doing.

[OwaisYunus1]

Thank you for the kind words. Bravo on being able to carry out maintenance work on your own vehicle, not a lot of people can do that so that is something to be proud of. You will eventually gather enough tools in shaa Allah and eventually be able to take on bigger tasks at home. That's how it goes with the tools arsenal, you keep adding to it.

About the tools, I have a toolbox with all the essential tools and then some. I've built it over the years and a stash of things from years of working on cars myself. The welder is a 280amp MMA welder. About the lift/engine hoist, this is a hoist that I made myself using C-Channels. The Chainblock used with it is a 2Ton one. Regarding what I do for a living, my field is Project Management.

[OwaisYunus1]

Thank you! I'll keep sharing more updates on the project.

[OwaisYunus1]

Thank you so much for the kind words. I'll definitely share more photos of the progress in shaa Allah.

[OwaisYunus1]

Thank you for the appreciation. The car in question is a very well kept vehicle and all original and one of the early production units so the build quality is much better than the later years. However, I've taken measures to improve the rigidity of the chassis and have paid special attention to not cutting corners on the swap.

[Mun33b]

Great then. The shock towers and cross member are way thin in guage then the fabrications, interested to know how you reinforced. Doing this with MMA and not burning through, you must have the skills.
My tig welder sits collecting dust these days, this thread revives few things.