Which engines are compatible with this swap kit and what kind of power can it support?
There is a wide selection of K series engines that you can choose from. There are plenty of options to choose from to suit your budget and goals. You'll quickly find that the price point for these engines (and transmissions) are a part of what makes this swap kit special. With the rising prices of SR20DET's and the decrease of KA engine availability this is a sure fire alternative with near infinite aftermarket support and capabilities.
For those wanting a 2 liter engine you'll want to shop around for a K20 engine. As easy as that sounds, there's a handful of variants that can make your shopping experience quite confusing. Let's look over your options.
*K20a3 - These are found in the 02-05 Honda Civic Si (EP3) and also in the base model Acura RSX. These engines are rated for 160hp and have a redline of 7200 rpm. This no frills engine can be found for as cheap as $300 and will commonly be found at used JDM engine depots for around $600. These engines feature 9.8:1 compression, vtec on the intake side only and variable cam timing up to 25 degrees. These engines don't mind a little boost and have no issues being abused to the 300-350whp range.
*K20a2 - These are found in the 02-04 Acura RSX-S. Rated at 220hp these are the first engines to start putting the K series on the map. Known for its 11:1 compression, 50 degrees of variable cam timing and 8200 rpm redline stock. These engines have no problem revving to 8600 rpm's stock and will gladly support the ballpark of 500whp(and more) without the need of forged internals. These can be found on today's used engine market for anywhere between $900-$1500 on average.
*K20z1 - These are the next generation of the K20a2 found in the 05-06 RSX-S. These engines carry a slightly higher redline, a larger intake camshaft and slightly stronger valve springs. These engines are slightly more expensive and can be found for anywhere between $1200-$1800.
*K20z3 - These are found in the 06-11 Honda Civic Si. This engine is very similar to the K20z1 but uses a slightly different casted cylinder head. The intake flange uses an integrated water outlet flange so please be aware of that when setting up your manifold. These engines are also very capable and had high production numbers for North America. These engines can be typically be found for around $1100-$2000.
*K20A(R)- These are the most sought out after engines in the Honda K20 lineup. These engines came in the EP3 Civic Type R, DC5 RSX Type R, and Accord Euro R(what we know as a TSX in the states). These engines feature a slightly higher compression of 11.5:1, larger camshafts on the intake and exhaust side, a slightly better valve job and valves, stronger valve springs, and fine balanced internals. These engines have no problem being spun up to 8800rpm's stock and with proper tuning will handle the same abuse under boost as the other K20a2,z1, and z3 variants. It's rare to find these engines as just a longblock but when they come about expect to pay anywhere from $2600-$3500 on average.
When shopping the JDM engine depots for your K20 please be aware that the engine code on the blocks are different from what we have in North America. You'll find that all of the engines may be stamped with the same K20A on it and will have to be identified by their cylinder heads, manifolds, and other proprietary components. Please be sure to check what you are buying thoroughly. For the high output engines there is vtec on both sides. For low output there's only vtec on one side. For those looking for a Type R variant the red valve cover is a dead giveaway.
For those looking for a 2.4 Liter swap you'll be in the market for a K24. Newer generation single port exhaust k24(z) engines are currently not compatible with our swap kits. Here is a list of the ones that are.
*K24a4 - These engines are found in the 03-05 Honda Accord and 03-06 Honda Element. These will be the cheapest of the bunch with a price range of $300-$1000. Much like the K20a3 engine, these have a rating of 160hp, 7200 rpm redline and feature vtec on one side and have 25 degrees of variable cam timing. With their 9.7:1 compression ratio they are boost friendly and have no problems supporting upwards of 400whp.
*K24a8 - These engines are found in the 06-07 Honda Acccord and 07-08 Honda Element. Honda made slight improvements to this engine over the K24a4 but nothing that is very notable for performance. These engines also fall into the $300-$1000 price range.
*K24a1 - These engines are found in the 02-06 Honda CRV and feature a higher flowing cylinder head than the a4 and a8 variants. Although it still features the same one sided vtec and limited 25 degrees of variable cam movement it is known to make the most power out of the budget low output K24 engine varants.
*K24a2 - These engines are found in the 04-08 Acura TSX. This is the engine which our swap kit was built around and is an absolute monster for the money. This engine is rated at 220hp and features vtec on both the intake and exhaust side of the cylinder head. From the factory it was limited to 25 degrees of variable cam timing It's 10.5:1 compression ratio makes it very suitable for either a mild naturally aspirated build or all the boost. These engines will comfortably support 500whp(and more) with proper tuning. The updated version which existed from 06-08 brought a few updates to even further its performance. The updated cylinder head features 1mm larger intake valves and larger cams. These engines can be found on average from $700-$1500.
As with the JDM K20A engines the JDM K24A's all carried the same designation. Please check with your local JDM engine vendor that you are receiving the correct longblock. The typical dead giveaways are that the performance k24a2 style engine models had the following traits
- Non EGR
- 3 lobe intake and exhaust cams
- RBB stamped on the cylinder head
If you need any help choosing the best suited engine for your swap please feel free to contact us at 847-290-1531 or Tech@tougefactory.com
What is the difference between PRB, RBC and RBB cylinder heads?
The RBB is the designation for the 04-08 TSX Cylinder head(K24a2). The RBB port design is often overlooked but highly capable. It's small volume high speed intake side mates well with the design of the exhaust ports allowing it to support a good amount of power for both naturally aspirated and force inducted combos. The RBB is known to be an optimal choice for midrange when compared to the other cast offerings.
The PRB is the most popular of the K series cylinder heads which are found in the 02-06 Acura RSX-S engines(K20a2). They also are found in different variants of the K20 type R engines. Out of the box this casting offers the highest flowing intake and exhaust ports for maximum power figures in the high rpm range. Power gains are reflected further with larger cams or forced induction.
The RBC cylinder head is nearly a combination of the two aforementioned cylinder heads and is found in the k20z3 from the 06-11 Honda Civic Si. This head is also highly capable and offers a great mix between mid range and top end. These cylinder heads are commonly found on used marketplaces as their production numbers were fairly high in the US.
For any further information or consultation for your engine build please feel free to give us a call or email Tech@TougeFactory.com
Which transmissions are compatible with this swap kit?
E36 5 speed manual transmissions from the inline 6 models (323,325,328,m3)
E46 6 speed manual transmissions from the 330ci
*You will not need any of the OEM bmw shifter parts as we offer solutions for the linkage and shifter
*You will need a slave cylinder that is designated for the transmission you choose
What do I use for an engine wiring harness?
For the ultimate DIY you can use an engine wiring harness from an 02-04 RSX-S or 02-05 Honda Civic Si. You will need to extend and modify some of the plugs to reach and plug into certain sensors. You will also have a good amount of plugs in the harness that will not be used for you swap. For those handy enough and comfortable with wiring it's a budget friendly approach. The ecu end of the harness will mate directly into your common 02-04 RSX-S ecu when using a Hondata Kpro. We will be offering full plug and play solutions
for both OEM style ecu and common standalone ecu combinations by January 2020.
What are my ECU options? Can I do a Standalone? What if I already have a standalone ecu?
The most popular ecu for this swap is the Hondata K-Pro. It's capabilities rival some of the standalone ecu's on the market today. The Hondata Kpro also mates directly with common swap harnesses. There are jumpers that will make your OEM style harness plug and play into popular ecu's like the Haltech Elite and AEM Infinity. If you are currently running a standalone that can adapt with a jumper, making it run on the K series will require a new configuration and tune. We offer plug and play Hondata K-pro's that require no core here > Link coming soon! <
Is there any cutting or heavy fabrication required?
Our kit was designed to be as painless as possible. There is no major cutting or fabrication required to mate the engine and transmission to the chassis. The extent of fabrication involved will be relatively minor depending on which combination you end up going with.
Can I retain my Air Conditioning or Power Steering?
Currently we do not offer a solution for Air Conditioning. This is something that we plan on integrating sometime in the summer of 2020. For power steering your options are an electronic power assist
rack that we can fabricate for your car if it is being swapped in house or an electric power steering pump commonly found on the Toyota MR2 can be retrofitted.
What is the weight difference between this swap vs other swaps available for the S Chassis?
It's been noted that the LS1 manual swaps (aluminum block) will average around 490 lbs with SR20det's weighin in around 440lbs and the KA24's weighing around 460lbs. The K Series longblock mated to the
BMW manual transmission weighs around 400 pounds. Our engine placement and positioning is also optimized for chassis balance. Experience all of the performance with no compromises.
What year does my car need to be for this swap kit to work?
Our kit is catered to the S-chassis platform across the board. Our mounts, oil pan, subframe spacers, shifter assemblies and wiring harnesses are made to work for all S-chassis' ranging from 1989 to 2001 in both LHD and RHD configurations.
Will my K series engine clear the hood?
It has been confirmed that the S14 with a K24 has no issues with hood clearance. We will have photos and information for the s13 and s14 hood clearances shortly.
How will my ground clearance be?
Our oil pan is designed for optimal ground clearance. As a full kit our subframe spacers and engine mounts will place the pan level with the subframe leaving your front power brace as a lower hanging portion of the car than the pan and subframe.
Can I use my existing radiator?
The easier option for a radiator is to use an SR20DET style radiator. Both outlets for the coolant ports come out of the left side of the car requiring a little more fabrication work for the KA style radiator to work.
I'm turbocharged currently and I plan on turbocharging my K series as I swap it. Can i retain some of my existing components?
The first thing to address is the exhaust and intake side of the engine are opposite from the Sr20det and Ka24de. As of right now we only offer a V-band inlet turbo manifold but there are others on the market with other inlets that may fit. Those who are using mid mount (dual back door) intercoolers will have an easier time routing their intercooler piping. The K series engine when turbocharged can be catered to your desired response, powerband and power goals. Please feel free to reach out for some consultation on choosing your next components.