Honda Accord - K24 Engine Swap - Honda Tuning Magazin

Technical
In the previous "K-Swap For Less" article (April issue), I highlighted some simple ways to cut the cost of installing K-power. After gathering information on pricing and parts availability, I had estimated about $2,500 coming off the total cost by utilizing a K24 motor from an Accord/Element/CRV, instead of the usual K20A2 from an RSX Type S. This time around I'm documenting the actual swap process, but instead of just watching, taking notes, and snapping a few pictures, I thought I'd actually perform the swap as if I'd just read the original story.

Of course, the downside of a K24 is that you won't get that infamous 200 horsepower, but you would get a K-swap, and lately, just having that is heading toward the top of most enthusiasts' lists. Now that more aftermarket support for the K24 has surfaced, as well as the excellent torque that the 2.4L offers, this budget swap can reap outstanding rewards over a D, B, or even H series swap.

The problem with doing a 160 hp/160 torque K24 swap is that the manual transmission from the Accord has a different type of bell housing compared to the RSX and EP3. And at the time, all swap mount kits would only work with the RSX/EP3 trannies.

However, Hasport has stepped up once again to lead the industry. They now have a kit for the EH/DC chassis that will let you use the Accord five-speed, and even the TSX six-speed. Additionally, by mid-summer, they should have the '96-'00 version available as well. At that time, Hasport will also have a dual height version similar to the EKK2 available.

Here's the quick breakdown of this new swap: you'll be using the standard K24, (not the real VTEC one, but the other one). With more than 300,000 Accords made every year since 2003, these engines are pretty much everywhere. High mileage units at yards that have a large inventory can be as low as $300. The standard K24 is in the 2003-up Accord and Element, and the 2002-up CRV.

The Accord is your source for a cheap manual transmission too. The units from the Element and CRV are set up for AWD, so their cases are completely different once again. But the Accord sold in decent numbers with a manual transmission, so you can probably find them from $300-$500, depending on condition. The bonus to the Accord transmission is its shifter box and cables. That's at least half the cost of RSX stuff.

Using Accord parts is essentially the cornerstone to this swap, and where the major savings come in. But we found a few other savings thanks to Hasport and the forums. Up first is a bracket set from Hasport, which allows you to use the alternator from a '96-'00 Civic as not only the alternator for the K24, but also the belt tensioner in a non-power steering and A/C-equipped swap. This is huge because the aftermarket solutions, even an ep3 idler, can cost $100 or more. On our '95 Integra four-door, we wanted to keep the power steering, so we didn't use this. But because we kept the K's power steering pump, we could also keep the original tensioner.

Next was the fuel supply system. The K24 doesn't use a fuel return from the fuel rail, but the Integra does. What's usually done is a full blown kit, from someone like K-Tuned, that includes lines, AN fittings on braided hose, a billet fuel rail, and billet fuel pressure regulator (FPR). No doubt, something like this is going to look incredible, but it could also top $500. Keeping our budget in mind, we went the eBay route. A simple Chinese FPR with all push-on line connections is less than fifty bucks shipped. I'd never use one of these things for a turbo engine, but for a constant pressure setup like the K24 requires, it's a perfect fit. By adding just one twelve-inch piece of fuel line, we had the entire system connected with parts that were already under the hood.

A few other pennies were pinched with the clutch line, power steering hose and more, but the captions will display those. The rest of the story, however, revolves around the old saying "the devil in the details."

Physically performing this swap with my own two hands wasn't so I could put wrench to bolt, but rather to try and help readers out when they go to do a swap that's really not commonplace just yet. Since we're not using RSX-S stuff, there are many new parts, and in typical Honda fashion, many things are interchangeable. On the flip side, there are some other parts that aren't so compatible.

The Swap
The first thing you're going to stumble on is the engine. The Accord K24 is going to be the easiest to get and 95 percent of the time, the cheapest. They are just everywhere. We paid a bit more for our '05 unit, but it only had 35,000 miles on it. Engines that have clocked over 80k were only $300. Next, you're going to need an Accord five-speed and shifter box with cables. Unfortunately, the yards often don't care about the cables. They often will have the shifter, but 90 percent cut the cables on the tranny when just pulling two cotter pins would actually save the cables.

So here's your big tip for getting the engine and trans. Try to work with one of the larger national yards like LKQ first. If you get lucky, they will still have something in a car and you can get it all in one shot. But their process works to just completely disassemble the cars as soon as they come in. If you strike out with them, do a 180 and try a local yard. Here is where you can talk to a counter guy who might actually enjoy cars and be interested in what you're doing. More often than not, in an attempt to save money, local shops won't pull anything until it's sold. That means everything you need will still be in there. That's a good thing, because while you might find low prices and cherry stuff at the big box, you're going to get nickel and dimed to death like I did. The K24 came as a long block only. No accessories at all, and it even had a broken TPS. I was able to exchange it for a different long block when I explained it had to have an intact TPS, but had to get the alternator, starter, and P/S all separate, at about $35-$50 each. The transmission was also cheap and had low miles, but was just a transmission. Even an aftermarket clutch and flywheel was too much, so it was the local little guy (Alma Imports) to the rescue. They let me walk the yard and we pulled a flywheel and clutch from an Element. We also took the complete engine harness (both sections).

That brings me to some of the electronics involved in this swap. Unfortunately we can't use the Accord engine harness. It splits in the engine compartment like an EH. Here's what works-'02-'06 RSX or '02-'05 CRV. The '03-'05 Element works too, but you'll have to re-pin it. It's similar to an OBD 2a and 2b system. The plugs are the same, but Honda shifted some of them around a bit. Since Hasport did all the wiring, they performed the re-pinning ('05-'06 RSX will also have to be re-pinned).

The last piece here is ECU. The Accord and Element have the same engine. The CRV is a little different. It doesn't have an EGR and uses an IAB-style manifold similar to the base model RSX. But it has the same pin-out as the RSX. Since running a K24 on a K20 ECU isn't right, this swap has a manual transmission CRV ECU. Why not the Accord or Element? Mostly because of the different pin out, but also because the immobilizer work around isn't compatible with those ECUs, and the CRV ECU can also be converted to a K-Pro. The others can't. To get around the immobilizer and multi-plexer issue, K-Tuned came to the rescue with their little black box that kills them both. This little beauty requires just four wires at the ECU, and two big problems are completely eliminated. Getting an ECU with a key and transponder was just not happening no matter how many yards I called, and K-Tuned's box just made it too easy at a bargain of just $160.

The rest is basically the same stuff you'd encounter during an RSX-S swap. Same half shaft, same custom axles, same wiring conversion from Hasport or DIY, install is the same, and the swap header requirement (yes, the K-Tuned swap header does clear, even with the taller K24 block). Overall, it's about the same number hours to complete the work. I was able to get some huge help from Superior Racing Development (SRD) in Tempe, AZ, so many thanks to them!

This K-swap for the masses should make for a huge boom in the swap biz and breathe new life into some of the older chassis. No, it's not 200 hp, but 160/160 is still a massive step up from a D16, even from a B18B. And the torque output compared to a B16 is a night-and-day difference. Already I've heard of RSX auto ECUs being reprogrammed with RSX-S six-speed codes, but with the immobilizer and OBD 2 turned off-perfect for swaps. In time, I'm sure it will be the same for this swap.

The Devil Is In The Details
All the K24s will work. Just watch out for Mass Air Flow (MAF) and electronic throttle versions, you don't want them. They are generally '06 and up.

The Accord five-speed and TSX six-speed are the only trannies you can use. The Element and CRV are considerably different since they have an output for AWD.

Most engines have a broken TPS because of front-end collisions. An Accord/Element engine can only use an Accord/Element TPS. Get an engine with a good TPS, make sure it's the first thing you check.

CRV engines will likely have a good TPS as it's protected with a metal shield, but you can't use it on Accord/Element engines; its rotation is the opposite.

The coolant inlet or thermostat will likely be broken too, and it's plastic. The Accord/Element are the same, but the CRV is awkward enough that a different radiator hose needs to be used. The housing is about $40.

If you can't find Accord shift cables, don't worry, they're cheap. Online, they're about $100 brand new.

Any manual transmission RSX or '02-'04 CRV half shaft will work. The Accord/Element and TSX are too long.

The '02-'04 CRV manual transmission ECU is the only one we know of that will work because of its pin-out. The Accord/Element ECUs make for an unknown conversion harness plus the immobilizer/multi-plexer problem.

Get the primary O2 sensor with the CRV ECU. Most of the time the yard will have it on hand.

The chassis' speedometer isn't going to work without a convertor box from someone like Dakota Digital.

An EP3 radiator is a great choice because it drops right in, is full size, and has a fan switch in the bottom of it, but any radiator that fits can be used.

The radiator hoses are a crazy mix. Buy couplers to cut and paste them together.

Note: Only the costs that we could lower are shown here. Labor for this swap should be the same as a K20a2 swap. Anything needed from shifter box installation, to fuel lines, to the crazy wiring, is all the same. The savings come from using alternative parts.