Honda K20 / K24 - What makes it GREAT? ICONIC ENGINES #11

Welcome to the dark side. We have airflow, an amazing intake port design, an incredible aftermarket. Coming soon, to a swap near you - the Honda K20 and K24

So first, a bit of history. The K20 first appeared in 2001, very soon after Honda's F20C engine that heralded many of the amazing technologies we would see in the K20. The first cars to get the K20 engine in 2001 were the JDM EP3 Civic Type R and the Integra Type R. Europe got the K20 in the same year in their version of the Civic Type R. Australia and New Zealand got their K20 in 2002 in their Honda Integra Type R. USA got it's first K20 engines in 2002 as well, in the Acura RSX and the Civic Si. The first K24 engines also appeared in 2002 in the Honda CR-V and the JDM Accord Type S. Very soon after this the K20 and K24 engines spread like wildfire throughout the Honda model range, powering much of it's vehicles (anything from the Honda Odyssey to the Honda FR-V and many cars in between)

Today, 19 years after it's introduction the Honda K20 and K24 engines are still as popular as ever, surrounded by an incredible aftermarket, enthusiasts, tuners and racers all around the world seem to be creating ever more impressive builds. This is likely the greatest testament to the brilliance of this engine's design.

But not all K20 and K24 engines are the same. They differ between each other substantially and can be divided into performance and economy versions on the K20 and K24. The performance and economy versions are different from the very core. Inside a k20a3 engine for example you will find a forged steel crankshaft, while inside a k20a2 or a k20z1 or k20z3 engine you will find a forged steel crankshaft that is also fully counterweighted, something that's important if you want so spend a lot of time in high rev range. The connecting rods and pistons are different too. Performance k20 and k24 conrods are beefier with a higher tensile strength. Pistons are cast and have molybdenum coated skirts in all k engines, but they feature noticeably larger domes for higher compression in performance k20 and k24 Honda engines.

But perhaps the biggest different is in the v-tec system of these engines. Both performance and economy honda k20 and k24 engines feature i-vtec, which adds intelligence to v-tec. In reality it adds camshaft phasing, the ability to advance or retard camshaft timing based on various inputs given to the engine's ECU. Now performance i-vtec features has three two different camshaft profiles, a mild one for low rpms and an aggressive one with higher camshaft duration and lift for higher rpms. In addition to this it has VTC, which is the variable camshaft timing we already explained and described. In contrast to this economy ivtec functions in a different way. At low rpms in opens just one intake valve fully and the other only slightly to prevent fuel from pooling behind the valve, this saves fuel and improves emissions. At higher rpms both valves are opened, but lift and duration remains unchanged. Also, economy i-vtec doesn't have VTC and has nothing variable on the exhaust valves.

Another important feature of the Honda k20 and k24 is a narrower valve included angle, compared to older Honda performance engines such as the B16 or B18. This enabled engineers to design an optimal intake port shape and maximize airflow. Stock K20 heads are capable of flowing 290-300 cfm, which is more than impressive. The other reason why k20 and k24 heads flow so well is the size of their intake and exhaust valves. k20 engines come with 35 mm intake and 30 mm exhaust valves, while in some k24 you will find 35 mm diameter intake and 31 mm diameter exhaust valves on some k24 engines.

The potential of the k20 and k24 means that k-swaps are everywhere now, and people have ventured well beyond the usual k20 / k24 into ek, ef, eg, civic or da integra. Nowadays k20 are often making into rwd chassis cars too.

When it comes to naturally aspirated tuning, the k20 and k24 engines are one of the few engines capable of reaching 300hp with relative ease (it's not easy) and can generate as much as 500 NA hp if you're crazy enough. But of course everyone's into forced induction nowadays and turbo k20 and k24 as well as supercharged ones abound. Bolt on kits are everywhere and you can build pretty much anything, the only limits are the thickness of your wallet and the sky. "Safe" turbo power for a stock k20 or k24 block is around 300 hp, but many people have gone beyond that, whether it's on borrowed time or not, really depends mostly on your tuning. If you're willing to spend on forged pistons and maybe even reinforce the block with some block guards, upgraded fasteners and ductile sleeves the k20 / k24 is ready to take you beyond 1000 hp.

A very special thank you to my Patron:
Daniel

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#d4a #iconicengines #k20 #k24

[TonyStark-iirv]

After watching this vid. Ive decided to swap out the Arc reactor out of my Mark IV for a K20

[dvtcu]

theres an article interviewing Francesco Morettini, ferrari's chief engineer. when asked which engine he liked from another manufacturer, he said the s2000's power plant, and that it was "truly remarkable".

[wing]

As a owner of a 2005 tsx is amazing how good and strong after 15 years later it still runs like new

[HorribleHarry]

I’m new to the Honda thing... you explained things better and more clearly than any other Honda engine in video I have seen. Thank you very much!

[HondaStreetGarage]

Great video! you used a pic of my k20 swapped ej! @4:46 thank you!

[MusicianKnowsBest]

Dude, this video is incredible. The knowledge, information, and detail is on another level compared to most YouTubers who just go over the basic info and say "So yeah because of these specs they're a great engine" lol. Please keep doing these videos with as many cool engines as possible. I really, really look forward to your videos! You're doing a great job, man, so keep it up! I hope your channel continues to grow because you definitely deserve it. Have a great day man just wanted to send some praise and a thank you your way!

[Kunfucious]

Man I wish I had this info when I was younger and fixed up my Honda. These types of videos are what makes YouTube priceless for me. So much free information.

[TheLiamis]

Asked an engine build specialist what I'd the best engine. "Honda" he said. Reliable, durable, high rpm, and lots of power.

[rkdz]

k20 in my toyota MRS. Amazing engine! the sound above 8k is just orgasmic. special engine for sure. one day it will hit 300whp NA.

[fueradecampo]

The rap was everything. You are a master and anyone can tell the passion you have for a good piece of enginnering. That's why I want to change my R18 2009 Civic to an K20 Si. Cheers from Argentina. Great stuff to watch and learn.

[SpearTheSeas]

You should swap a k24 into your mr2. Hux racing sells mounts and has a service to merge the the wiring harness.. I just bought an aw11 mr2 with no motor for 1k. .... right now I'm going through all the suspension bushings adding some WAT coilovers rebuilding the steering rack.. basically just follow your suspension series and repairing any rust I find along the way. I'm gonna use a K24A2 and a 6 speed k20 trans with an lsd.. :) all you need are the mounts and some slightly shortened and welded Honda b series axels.. they have the same exact spline and diameter as the toyota axels...:) This is a super balanced strong and cheap totally underrated swap for aw11 mr2s in my opinion.... and I'd love to see a build series on it!

[frankgile]

Now that you did the K20/K24 episode, you'll have to do the F20C episode at some point...

[shadowboy]

The reason you want a shallow valve angle is because it allows a flatter combustion chamber. This in turn offers a better compression ratio for better thermal efficiency without needing to have a large piston dome (just look at the B16B pistons, some time).
A wider valve angle increases combustion chamber size and in turn makes room for larger valves.

[antrinh]

the k series is very affordable now, most people would seek the k20, but i prefer the k24 from an acura tsx. i have an 06 accord 5 speed manual with the "economy" k24a8 and an toyota ae92 with the 4age. the accord is my daily beater and i took it anywhere, i took trips to sf and back which is 420 miles from me. car never give me any problem, run smoothly like a charm, mpg was fanstatic once i got on the freeway( average 33-35 mpg at 75-80mph), in town around 22-24. i did a couple poor man mod for the motor, swapping the intake manifold, throttle body from an acura tsx k24a2( i think), exhaust header from dc sports and cai( not short ram). and it does give it a very noticeable throttle respond. the ae92 is my toy, i drive it on my days off, and i can go anywhere with it also but the accord is the best car interm of comfy, mpg and also fun ( with my poor man mods) to drive. maybe the ae92 give me a little bit more smiles while reving it up but the accord really give u that comfy and torquie feeling on a long drive.

[fmixthings]

Great info. The scream at 28:45 made me smile. I've had my 2003 RSX since 2005 and keep thinking about swapping the motor to a classic Mini. But I also want to build that car and have fun with it. Tough choice.

[gavinsmith]

Just bought a 2007 civic type R ( fairly cheaply ), changed engine oil, filter an plugs etc, and that engine bounces off rev limiter no problem and purrs like a kitten at low rpm, six speed box as smooth as silk, i swear to god it drives like new, i am so impressed with it.

[davidkris]

First I watched the 4AGE and wanted to build some of that Cosworth inspired goodness. But then I watched your 2ZZGE video and decided I couldn't resist the newer tech improvements. Now I've watched this and I'm making room in the garage for the K20 I want to build. Will you stop making these great videos so I can get started!?! (also just had to go back and thumbs up all these since I watched them in order on auto play (even watched a bunch of ads just to help the revenue!) Thanks for the great vids!)

BTW - it may not be iconic, but I'd love to hear what you think about the miata BPw4 motor.

[dannymac]

Really really enjoyed the K20Z3 especially, and driving my 2006 Civic Si for nearly 7 years.

Moving on to an AP1 S2000 and the F-series, it definitely felt like a more raw experience, more akin to the B-series.

So glad they firmly cemented my love for high-revving naturally aspirated engines.

Next stop: 4.0L flat-6, 6-speed, GT3 suspension, and AWD removal in a 991.2 Targa GTS body. 😍

[kseriesdan]

Like the video. Honda has done a good job with the kseries. The last of the great Na 4cylinders. R. I. P Na cars as turbo has now taken over

[solicitutoob]

Love my K20 (2002 Acura, RSX Type-S). I didn't baby it but i didn't abuse it either. 320k miles. Original clutch. No engine work. Super reliable engine. Only suspension mods: coilovers, sway bars, 17 inch rims (2002-2003 rims were 16 inch). This out handles most cars.