How Much Horsepower Does A K&n Air Filter Add

Honey it or detest it, Honda'south K20 engine has certainly stood the exam of fourth dimension. With its fantastic reliability and huge tuning potential, information technology'southward easy to encounter why then many enthusiasts are swapping their engines for the K20.

honda k20 rx7 fd3s swap

Honda G-Series History
How much horsepower does a Honda K20 have?
Which cars take the K20 engine?
Honda K20 Modifications & Tuning
K20 Engine Swap
K20 Reliability & Mutual Problems
Determination

Introduction

You may want to take a seat before we announce this one equally it may come as a daze, merely today we're going to expect at the heart of the evil archenemy of most drifters.

That's right, whether you dearest them or hate them, it's time to give a little appreciation to the notorious engine which has handed Honda fans beyond the earth bragging rights since 2001.

Jokes aside, as much as nosotros beloved globe-trotting, we knew as soon as we made the decision to create our engine spotlight guides that nosotros'd requite the fans what they wanted, and would you lot believe it, some Honda fans similar globe-trotting too!

This video explains why the K-serial is ane of the finest engines Honda ever produced:

Honda is undoubtedly one of the biggest names in the JDM community, and certainly one of the largest when information technology comes to the aftermarket tuning scene. Owners may well discover themselves at the end of a few too many jokes when it comes to hanging with drifters, but ofttimes their cars are certainly not to exist laughed at, or underestimated.

Honda has undoubtedly created some of the about impressive four-cylinder engines to ever become into mass production, and although the initial reaction from the hardcore B18 owners wasn't the greatest, the K20 has transformed itself over its history and can now confidently take its spot with some of the best.

That transformation certainly didn't happen overnight, nor was information technology elementary to comprehend, and then we've decided to make this guide to show you lot how the K20 has evolved to the present day, before explaining how you tin continue to unleash its full potential.

Looking to venture into the globe of motorsports and get noticed with your K20-powered weapon? You'll want to check out our So, You Want To Accept Up Extreme Motorsports? guide.

Honda K-Series History

It'south been near two decades since Honda initially introduced its K-serial engine family, and a lot has changed along the way. At that place certainly hasn't been a lack of revisions and updates which can become a petty challenging to follow, so we've conveniently broken them down in our history section.

If you lot've made it this far, you'll already know that not each and every K20 engine is the aforementioned. If you opt for the wrong one, you may well take been meliorate off sticking with the B-series.

A lot has changed over the about-two decades since the K20's launch, and with the world now focusing on greener emissions and fuel consumption over performance and tuning potential, opting for the latest powerplant isn't always the best determination.

Information technology all began for the K-series at the stop of 2000, as the globe realized that the planet wasn't coming to an end following the 'millennium bug', Honda had a fob upwards their sleeve that they were about fix to launch to the earth.

The first motorcar to reach the marketplace with the K20A engine was the JDM-merely model Honda Stream. This engine would become the predecessor of several much-loved powerplants, such as the B16, B18, B20, D16, H22, and F20. Whether Honda enthusiasts loved or hated information technology, it was the start of a new era.

During its twelve-twelvemonth product run, the B-serial had garnered a cult-like following, which would soon outburst in east-wars every bit the K and B series owners fought it out behind their keyboards to fence which was the more impressive.

That's right, drifters, you'll be glad that Honda owners aren't purely argumentative towards us!

honda k20 dyno meet

As time progressed and the K20 evolved, things seemed to settle downwardly, and although almost owners have a articulate favorite, that's completely understandable as they both have their advantages and disadvantages.

Well-nigh K20 owners will debate that there'south "No replacement for displacement", and they have a valid point, especially if you lot're looking at naturally aspirated builds. However, let'south non forget that B18 race-engines are capable of producing over 1,000hp. Your stock K20 probably isn't going to exist also much of a lucifer at that place, unfortunately!

Today we're here to focus on the K-serial, which a four-cylinder, 4-stroke engine which opted to move abroad from the old standard timings in favor of computerized ignition timings. With an overall ameliorate design quality which included a more refined valvetrain and improved build quality, it certainly had some positives over its predecessors.

Up until the K20, Honda had get famous for their counter-clockwise-rotation engine architecture, just the K20 flipped that effectually and opted for clockwise to position the engines frazzle side toward the rear of the vehicle.

honda k20 vw caddy

The K20 initially hit the U.Due south. marketplace with the Borough Si, CR-V, and RSX in 2002. Honda's aim would be to produce an engine which would come across modern-day emission standards whilst also improving build quality and reliability.

Although you'll soon see that at that place are a huge variety of K-series engine designations, near of them closely relate to the K20A2 and K20A3 engines. Both are extremely similar, featuring Variable Valve Timing and Elevator Electronic Control (i-VTEC), but the principal differences lie within the valvetrains and VTEC implementation.

Information technology's time to take a closer wait at the various 1000-serial models to help you decide which ane is best for your needs, whether you lot're looking to purchase a Honda, or looking to accept advantage of the K20 in a different platform.

K20A

This engine was produced specifically for the JDM (Japanese Domestic Marketplace) and was the offset K-series to hit the market in for the 2001 model year.

Initially capable of producing 217hp at eight,000rpm in stock form, with up to 152lb/ft torque at vi,100 rpm and an impressive redline of 8,400rpm in the Honda Integra Type R, a later revision saw it reach 221hp and 159lb/ft torque in the 2007-2001 Borough Type R FD2.

Head porting is made for this engine at the mill and it used a 62mm throttle trunk. It featured balancer shafts, a more rigid crankshaft and high compression pistons (CR = 11.5).

Reinforced connecting rods are installed into the cylinder cake, dual valve springs, dynamic camshafts, a lightened flywheel, a PRC intake manifold, improved 4-ii-1 header, and a 54mm exhaust arrangement were used aslope 310cc injectors.

For the 2007 model year, the K20A received an updated version. This included an RRC brusque intake manifold, 64mm throttle torso, improved intake and exhaust head ports, reinforced connecting rods and a compression ratio of 11.7. As for the VTEC, this kicked in earlier, at 5,800rpm opposed to the 6,000rpm of the previous version.

This engine was only available on the JDM Borough Type R FD2 and fabricated it capable of achieving 221hp at 8,000rpm with 159lb/ft torque at half dozen,100, the rev limiter was now triggered at 8,600rpm.

K20A1

This engine was only ever featured in the JDM-model Honda Stream for the 2001-2006 model years, in both FWD and AWD applications. Information technology produced betwixt 156-158hp at six,500rpm with 139-140lb/ft torque at 4,000rpm and a redline of vi,800rpm.

Needless to say, information technology certainly wasn't the most impressive K20 to hit the marketplace!

K20A2

This is the nearly established of K-series engines and is based off an all-aluminum block and DOHC with a 16-valve cylinder head. Unlike the economic system-focused K20A1, this added uprated camshafts, a PRB intake manifold, alongside larger intake and exhaust ports.

Its compression ratio was slightly lower at 11.0:1 and the i-VTEC arrangement comes into play at 5,800rpm. This produced 200hp at 7,400rpm with 142lb/ft torque using 310cc OEM injectors.

K20A3

You may be expecting this to exist an upgrade over the A2, only yous'd exist very wrong! Despite looking most identical to the K20A2, the changes were generally internal in favor of improved economy figures.

This model was capable of producing only 160hp (or fifty-fifty less in the 2.0 Civic, at 155hp) and 141lb/ft torque from 270cc injectors. Compression was down to 9.eight:1. A PPA intake manifold was used which was triggered at 4,600rpm and i-VTEC kicked in at 2,200rpm.

K20A4

This model is based on the K20A3 for the USDM 2003-2007 Honda Accordance and 2002-2006 Honda CR-V.

K20A6

This model is based on the K20A3 for the European and Australian 2003-2006 Honda Accordance.

K20Z1

With Acura performing a mid-model update on its RSX, the updated K20Z1 was chosen for the last 2 years of production.

There is very little divergence betwixt this engine and the K20A2 other than slightly improved camshafts, a higher-flowing catalytic converter, and larger intake and exhaust. This provides an additional 10hp.

K20Z2

This engine was a replacement for the economy K20A1, featuring a new longer-runner intake manifold, restyled camshafts, and drive-by-wire mechanism. This was capable of merely 153hp at 6,000rpm and 139lb/ft torque.

K20Z3

Based on the K20Z1, but with unlike camshafts and an RRB intake manifold. This achieved 197hp at 7,800rpm and at 139lb/ft torque at half dozen,200rpm.

K20Z4

Based on the K20Z3, except with an RSP intake manifold upgrade this fourth dimension. This increased the power to 201hp at 7,800rpm and 142lb/ft torque.

K20C1

After Honda ceased production of the original K20 engine in 2011, product was put on concur for some time until its rebirth with the newly-designed K20C1 engine in 2015. Despite being built in Ohio, this turbocharged variant was only bachelor on the European market and enabled Honda to produce a far more than powerful engine.

With a pinch ratio of 9.8:1 and 306hp at six,500rpm and 295lb/ft torque at 2,500rpm, it certainly packed a dial.

This power was too achieved by adding a new lightweight crankshaft, forged connecting rods and modified pistons. It too gained a new cylinder head with a straight injection system and an i-VTEC system is integrated for the intake and exhaust valves.

Subsequently improving the intake and exhaust head ports, a single-scroll MHI TD04 turbocharger was added and produced ane.58 bar of heave (23.2PSI).

K20C2

After the impressive output of the K20C1, Honda returned to their economy range with this naturally aspirated version of the K20C.

This time an i-VTEC head with a direct injection system and improved combustion chambers was used. It used the same lightweight crankshaft from the K20C1 with modified pistons, providing a pinch ratio of 10.eight:i.

This produced 158hp at half dozen,500rpm and 138lb/ft torque.

K20C3

Based on the K20C1, but with a x.8:1 compression ratio and an MHI TD03 turbocharger. This produced 272hp at 6,500rpm and 273lb/ft torque. This engine was produced for the Chinese domestic market and is very rarely found.

K20C4

This was over again based on the K20C1 for the U.Southward. and Canadian markets, simply with a ix.eight:one pinch ratio using an MHI TD03 turbocharger with the boost force per unit area set at 1.43 bar (20.8psi) and generating 252hp and 273lb/ft torque at 1,500-4000rpm.

From 2015 onwards, Honda has connected to extend the K20's legacy with their mod-24-hour interval K20C-series subsequently the K20A was initially replaced with the R20A.

How much horsepower does a Honda K20 have?

Every bit we covered in our K20 history section to a higher place, which we highly recommend checking out if you're looking for a specific model, the horsepower figures within the K20 range varied hugely.

honda k20 on throttle bodies

For the K20A serial, the highest horsepower rating was 215hp at viii,000RPM with a summit torque of 149lb/ft at 7,000rpm.

With some models producing 155hp (K20A6), others were capable a far more impressive 306hp at six,500rpm in its stock turbocharged form (K20C1.) This was classed as a "square engine" due to the diameter and stroke measuring an identical 86mm.

Interested in the history of other cars? Make certain you head over to our 11 Best JDM Cars Of The Nineties guide!

Which cars have the K20 engine?

K20A

2001-2006 Honda Civic Blazon R (JDM)
2001-2006 Honda Integra Blazon R (JDM)
2002-2008 Honda Accord Euro R (JDM)
2007-2011 Honda Civic Blazon R (JDM)

K20A1

2001-2006 Honda Stream (RN3, FWD)
2001-2006 Honda Stream (RN4, AWD)

K20A2

2001-2006 Honda Civic Type R (EDM)
2002-2004 Acura RSX Type S
2002-2004 Honda Integra Type R (AUDM/NZDM)

K20A3

2002-2006 Acura RSX
2002-2005 Honda Borough Si
2002-2005 Honda Borough SiR
2002-2005 Honda Civic Type S
2003-2006 Honda Civic ii.0 i-VTEC (Sea)

K20A6

2003-2006 Honda Accord (EDM)
2003-2006 Honda Accord (ADM)

K20C1

2015-present Honda Civic Type R (EDM)

K20C2

2016-present Honda Civic 60 (USDM)
2016-present United States Formula iv Championship

K20C3

2016-present Honda Avancier (Prc)

K20C4

2018-present Honda Accord

Honda K20 Modifications & Tuning

Honda's history with creating engines with heaps of tuning potential is certainly upward there with the all-time, and similarly to the previous generations, most models of the K20 are no exception.

Yet, nosotros volition country that if you either ain or are considering the economic engines such every bit the K20A1, K20A3, K20A4, K20A6 or K20Z2, we'd highly recommend not investing time and coin into trying to squeeze boosted performance out of these engines.

They weren't made with power figures in heed and you're probable to invest a lot of time and coin for minimal rewards.

honda k20 gold turbo

With your typical breathing upgrades such every bit a decent intake and a free-flowing exhaust, you're likely to see around 200whp from a K20A2. This is far easier to reach in the K20 than it is in the B18, which requires more extensive mods to hit the 200whp ballpark.

For those of you with JDM K20A, K20A2, K20Z1 or K20Z4, y'all've hit the jackpot when it comes to easily achievable power gains. By merely plumbing equipment bolt-on mods such as an RRC intake manifold, an FD2 throttle body, a common cold air intake system, iv-two-1 header, a ii.5" exhaust and a Hondata One thousand-ProECU y'all're likely to run across 230whp, making for a not bad setup, especially for street use.

If yous're looking to get further, larger throttle bodies, intake manifolds, cams, cam gears, valve springs and retainers, a larger exhaust, lightweight flywheel, and larger injectors will give you lot even more power. With even further mods you tin can as well achieve over 9,000rpm.

There'south also the choice to use the K24A2 cylinder block with the JDM K20A or K20A2 caput to build a 'K20/K24 Frankenstein'. This will give yous 2.4-liters of displacement. With larger pistons, the compression ratio is and then capable of being increased to 12-xiii.0:1.

With all-encompassing modifications, yous tin expect to hitting 300hp from an N/A engine and if you're willing to get all the manner with throwing coin at it, you can eventually attain a x,000rpm redline, merely be warned, this doesn't come cheap!

K20A Forced Induction

Once you've added all the costs involved in the Frankenstein build above, it may well make more sense to go with a K20 Supercharger Kit. In that location are several models bachelor off-the-shelf which can provide over 300hp.

If you're looking to make further supporting mods, 400whp can be accomplished with a supercharger.

If a supercharger isn't exciting enough, there's always the turbo option! With a Garrett GT3076R, stage 2 cams, valve springs and retainers you could well exist looking at even more than power.

Non sure whether a turbo or supercharger is best for your needs? Check out our Turbocharger Vs Supercharger - What'due south Best? guide!

Although the stock internals on a healthy engine are capable of handling over 400hp, we'd highly recommend considering transmission upgrades at this point due to the stock trans tending to explode around these power figures.

If you're looking to become all-out, a congenital bottom-finish with aftermarket sleeves could well go all the way to ane,000hp.

K20C Upgrades

With some simple bolt-on mods such as a cold air intake organization, a forepart-mountain intercooler, a full exhaust system with downpipe and Stage 2 ECU tuning, you can exist looking at 380hp with the stock turbocharger (around 280hp for the Accord Ten.)

K20 Engine Swap

We've seen some insane K20 swaps over the years, from Lotus through to Mini, and just near everything in-betwixt! Given its lightweight nature with impressive power figures from natural aspiration along with the potential for forced induction, it's easy to see why and so many people brand information technology their weapon of choice.

When we said insane, we weren't exaggerating. How does a ane,000hp K20-powered NSX tickle your fancy?

If you're because a swap, here are some of the essentials that you'll demand to consider.

Engine

Not only will you demand the engine, simply you'll besides need all the components that go with it, such as fuel lines, wiring harnesses and a complete transmission to match.

If you're breaking a car, y'all tin hands pull all of this yourself. Withal, if you've sourced an engine cake it may be a little trickier.

Accessories

You'll need the starter, alternator, and power steering pump (if equipped.) Information technology's besides worth remembering that if you'll need replacement pulleys if y'all're replacing air workout and things likewise.

Engine Management

Y'all'll demand the ECU from the original car, which should be provided with the wiring harness. You may well exist upgrading or tuning this, but it always makes life far easier if you lot take the original ECU to mitt.

Mounting

Information technology should go without saying if you've got this far, simply yous're going to need to consider how you'll be mounting the engine. For some cars, in that location are elementary off-the-shelf mounts, but if you're going for something more than extreme then you'll most likely need to consider having custom mounts fabricated.

Extras

It'due south worth refreshing or upgrading additional parts of the engine before you fit the engine in the bay while it'southward convenient. It can sometimes exist worth belongings out a little longer and extending your budget for some worthwhile upgrades.

Things similar an upgraded throttle torso tin provide decent ability upgrade potential for minimal cost.

K20 Reliability & Mutual Problems

Although the K20 is an extremely reliable engine which has often been known to achieve 'moon mile' condition, there are some potential issues that could arise, so it'south well worth maintaining it every bit all-time you lot can.

Besides the obvious routine servicing, typical maintenance can include valve adjustment every 24,000 miles. Valve clearances for a cold engine are 0.21-0.25mm on the intake and 0.28-0.32mm on the exhaust.

Camshafts on the K20 are rotated by a timing concatenation which has a service life longer than 120,000 miles. Information technology's worth checking if maintenance or replacement is required later this.

z car mini rollcage with honda k20

Every bit for the problems you may well encounter during your ownership, and which are well worth looking out for when information technology comes to buying.

If y'all're hearing a knocking sound from the engine, it'south oft not a good sign, yet, it tin sometimes hateful that the valves simply demand adjusting. However, if this hasn't been done for some time information technology can increase wear on the exhaust camshaft. This may mean that you'll demand to supervene upon the camshaft.

Oil leaks, as with all engines, can sometimes occur. It's most probable to be coming from the crankshaft'due south front seal and is a common trouble that simply needs a replacement part.

If you've got a rough idle, information technology'south most likely going to demand a simple clean-upwards of the throttle body or idle air control valve.

If you lot've got vibrations coming from the front of the auto, the mounts are going to be the first port of call. With highly worn engines, after checking the mounts, information technology result may lie with an elongated timing chain.

Engines produced between the 2000-2003 model years can sometimes suffer from the fourth cylinder overheating.

Conclusion

Although it took some convincing for the die-difficult B-series owners, the K20 certainly turned into yet some other powerplant than Honda can equitably exist proud of and in many ways was a big leap from the legendary B18.

You'll need to be careful with your choice among the many variations that were eventually made, if you go with one of the solid contenders then we have no dubiousness information technology'll serve y'all well.

With its i-VTEC engineering, it enabled significantly improved airflow and as well added curlicue on plug technology.

Its tuning potential makes it a fantastic pick for either upgrading your existing engine or using it for a swap to create a whole different creature. With up to 350hp achievable with the subsequently engines, they can somewhen be pushed to 1,000hp with all-encompassing modifications.

Additional Honda K20 Related Content

We've selected some of our favorite K20 YouTube picks for your viewing pleasance!

If you've not seen the Z Cars Mini's before, you've gotta bank check this out. Could this be the perfect combination?

Adam LZ takes a K20-powered Miata for a spin.

This Lotus Exige has fitted a supercharged K20 which is capable of hitting 9,000rpm!

Remember it's just FWD cars that opt for the K20? You'd be wrong! We tin't expect to run into this matter shredding tires!

Another K20-powered Mini, this time pulling off a 2.83 2nd 0-60mph!

How could we not complete our guide with a sound compilation video?!

If yous're also interested in the other engines that Honda has to offer, make certain you check out our comprehensive Honda B-Series guide.

Photography credits

Drifted would like to extend thanks to the post-obit sources for employ of their images:

Z Cars
SuperStreet
nate.stevens (Flickr)
Chris Sempek (Flickr)
Frank Markovich (Flickr)
Niall97

Written past Joe Terrell Drifted.com founder, motoring journalist and all-round car enthusiast. Read more than about Joe and the Drifted team on our virtually united states of america folio.