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I can get the K20 from CRV for resonable price. Is it worth to buy that engine and instal in to LS Integra. There are alot of differences in engines betwen K20 which goes in to RSX type-S or Civic type-r.

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the k series engine in the CRV is the k24a.

It does have differences from the other k20a engines.

Note that the I-VTEC in the k24a is similar to the I-VTEC in the k20a3 (CIVIC Si EP3)

The Acura TSX k24a is like the k20a2 out of the Acura Type S.

Originally posted by Targa250R-



The K20A3 like the CRV/accord/element k24a does not have a standard DOHC VTEC valvetrain as we know it from the B-series engines - the K20A3 should actually be called a "DOHC i-VTEC-E" engine, because it uses a VTEC-E cam setup. The K20A2 is the "real" DOHC i-VTEC engine, utilizing the standard DOHC VTEC cam setup we're all familiar with. To help you understand the differences between the K20A2 and K20A3 engines, I've included the following information from a post I made elsewhere:

Allow me to evaluate. Let's start out by defining some terms:

VTEC - Variable valve Timing and lift Electronic Control. At low RPM, a VTEC engine uses a normal cam profile to retain a smooth idle, good fuel economy, and good low-end power delivery. The VTEC mechanism engages a high-lift, long-duration "race" cam profile at a set RPM value (i.e., ~5500RPM on the B16A) to increase high-end power delivery.

VTEC-E - Variable valve Timing and lift Electronic Control for Efficiency. This system isn't really VTEC as we know it. At low RPM, the VTEC-E mechanism effectively forces the engine to operate as a 12-valve engine - one of the intake valves does not open fully, thus decreasing fuel consumption. At a set RPM value (i.e., ~2500RPM in the D16Y5), the VTEC-E mechanism engages the 2nd intake valve, effectively resuming operation as a normal 16-valve engine. Note: in a VTEC-E engine, there are no high-RPM performance cam profiles; this engine is supposed to be tuned for fuel economy, right?

VTC - Variable Timing Control. This is a mechanism attached to the end of the intake camshaft only which acts as a continuously variable cam gear - it automatically adjusts the overlap between the intake and exhaust cams, effectively allowing the engine to have the most ideal amount of valve overlap in all RPM ranges. VTC is active at all RPMs.

i-VTEC - intelligent Variable valve Timing and lift Electronic Control. This is a combination of both the VTEC and the VTC technologies - in other words, i-VTEC = VTEC + VTC. Currently, the only engines that use the i-VTEC system are the DOHC K-series engines.

Now this is where things get tricky - Honda uses the term "DOHC i-VTEC" for two different systems: The first system is used in the K20A2 engine of the RSX Type-S. The second system is used in the K20A3 engine of the Civic Si.

The First System (K20A2):

This system is pretty close to the older DOHC VTEC engines. At low RPM, the K20A2 uses a normal cam profile to retain a smooth idle, good fuel economy, and good low-end power delivery. At 5800RPM, its VTEC mechanism engages a high-lift, long-duration "race" cam profile to increase high-end power delivery. The only difference between this i-VTEC engine and the older VTEC engines is the addition of the VTC system. The intake camshaft has the automatic self-adjusting cam gear which continuously optimizes valve overlap for all RPM ranges.

Here we see an image of the intake cam lobes of the K20A2. Notice there are 3 lobes; the two side lobes are the low-RPM profiles, and the center lobe is the high-lift, long-duration profile which engages at 5800RPM. Basically the same setup as the old VTEC engines we are familiar with.



Now here we see the VTC mechanism - the gear on the end of the intake cam that adjusts valve timing (overlap) automatically on the fly.



This system is used in engines powering the JDM Honda Integra Type-R, Civic Type-R, Accord Euro-R, and the USDM Acura RSX Type-S and TSX.

The Second System (K20A3):

This system does not really conform to the "DOHC i-VTEC" nomenclature, as Honda would like us to believe. As I mentioned in my previous post, it actually should be called "i-VTEC-E," because it uses a VTEC-E mechanism rather than a standard VTEC mechanism. At low RPM, the VTEC-E system effectively forces the engine to operate as a 12-valve engine - one of the intake valves does not open fully, thus decreasing fuel consumption. At 2200RPM, the VTEC-E system engages the 2nd intake valve, effectively resuming operation as a normal 16-valve engine. There are no high-RPM performance cam profiles; this engine is tuned to balance fuel economy and power, rather than provide pure performance. On the intake cam, there is the VTC mechanism which basically is an automatic self-adjusting cam gear used to continuously optimize the valve overlap for all RPM ranges. This being a VTEC-E system - and not a true DOHC VTEC system - is the reason the K20A3 redlines at a measly 6800RPM, while the K20A2 is able to rev all the way to 7900RPM.

Here we see an image of the intake cam lobes of the K20A3. Notice there are only 2 lobes - there is a nearly round one used only for the low-RPM disabled intake valve, and then there is the regular lobe used by the other valve at low-RPM and by both valves at high-RPM:



This system is used in engines powering the USDM Acura RSX base, Honda Civic Si, Accord 4-cylinder, CRV, and Element.

Special note: The K20A3 engine used in the Acura RSX base has a slightly different intake manifold design from the K20A3 engine used in the Civic Si. The RSX engine uses a dual-stage manifold, similar in concept to the manifold of the B18C1 in the old Integra GSR. It uses long intake runners at low-RPM to retain low end power, and switches at 4700RPM to a set of shorter intake runners to enhance high-end torque. This accounts for the extra 9 ft-lb of torque in the RSX (141 ft-lb, vs. 132 ft-lb in the Civic Si).

Here is an image showing just how this dual-stage manifold works. On the top, you can see the low-RPM (long) runners are in use, and on the bottom, you can see the high-RPM (short) runners in use.



Myths:

1. The i-VTEC engine engages VTEC gradually, and not suddenly like in the old VTEC engines.

Wrong. The i-VTEC engine "engages VTEC" at a single set RPM, like always. Whoever started this rumor is a fucktard. Read the definitions above.

2. VTC engages at a set RPM.

Wrong. VTC is always activated. Read under "VTC" above.

3. The K20A3 engages VTEC at 5000+ RPM.

Wrong. Technically, there is no "VTEC" (as we think of it) in the K20A3 engine - it uses a VTEC-E technology, which engages at 2200RPM. Read under "The Second Sytem" above.
 

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Ok so now you know that the CR-V motor doesn;t have true i-VTEC in both cams.

The motor in stock with hondata will give you around 160HP and 160 torque. It is great for everyday driving and has a lot of midrange power. It cannot be revved more than 6800 RPM...

Some people use the k24a block and mate it with the k20a2 head from the type S.

See the article with the pictures at http://www.sportcompactcarweb.com/tech/0406scc_hybrid/




Hybrid How-To No. 15
K24 short block with K20A2 VTEC cylinder head

By Randy Hasson
Photography: Chris Felser

What and why
There's no substitute for displacement, except maybe technology, so in a perfect world you'd have both. If you're driving a Honda powered by the new K-series engine, there's a relatively easy way to get both. Take the big 2.4-liter block from an Element, CR-V, or Accord and mate it with the high-flow head from the K20A2 found in the RSX Type-S. It's almost that easy. Almost. This swap can be called a head swap or a block swap, depending on what you start out with and what you want to achieve. It can also be dubbed a "poor man's TSX engine." Regardless, you'll wind up with the intake and exhaust side VTEC system on top of a 2.4-liter block, and as we'll see, the marriage works.

There's VTEC, and then there's VTEC
Honda has used two very different VTEC systems on K-series engines. In spite of the engine's differences, both happen to be called i-VTEC. The first system, found on the K20A2 (RSX Type-S) and K24A2 (TSX) has three cam lobes for each pair of valves. At low rpm, each valve follows its own mild cam lobe. At high rpm, they both start following the third lobe, which has higher lift and more duration for better high-speed cylinder filling. This is the VTEC you're used to. The second system, found on the K24 (Element, CR-V, Accord) and the K20A3 (base RSX and Civic Si), is designed to minimize emissions and maximize driveability and gas mileage. In this system, there are two cam lobes, a normal one and a puny little atrophied one, for each pair of intake valves (nothing happens on the exhaust side). At light load and low rpm, each lobe opens one valve, so most of the intake air goes through the valve that's opened more. This creates a swirl in the combustion chamber that happens to be great for combustion efficiency. Floor it, though, and one valve won't be enough, so both valves follow the bigger lobe. Notice there's no screaming high-rpm race lobe here.

The "i" part of i-VTEC stands for VTC (don't ask us how they came up with that) the Variable Timing Control system that graces all of the K-series engines, whether they have the go-fast VTEC or the sissy model. VTC simply advances or retards the entire intake cam.
The block
K24 blocks are ready to make big horsepower numbers. The crank and rods are similar in construction to the K20A2 parts, but with beefier rods, bigger rod bearings and additional counterweights on the crank. The K20A3 engine, sourced from the base RSX and Civic Si, is built for less power and lower rpm. Honda got the extra 400cc for the K24 from both an increase in bore from 86mm to 87mm and an increase in stroke from 86mm to 99mm. The additional stroke forced a 19.7mm increase in deck height, which might only become apparent when you let the hood drop, so check those hood clearances carefully. Remember, this also means your exhaust manifold will move up 19.7mm, so make sure you have that kind of room, or prepare to make adjustments. Sales figures for the 2002-and-up CR-V, Accord and Element are already nearing a half-million, so you shouldn't need to stay glued to eBay for a chance for one. Expect to pay between $650 and $1,000 for a complete K24 engine in good condition. The K24A1 that sits in the CR-V has a 9.6:1 compression ratio, while the K24A4 found in the Element and Accord have 9.7:1. The other differences between the K24 applications, most notably the presence of EGR, used on the Accord and the Element, and a variable length intake runner system, found on the CR-V, are irrelevant since we're not using the K24 head.

Although we haven't seen any yet, it's possible Honda will come out with ultra-efficient K24s for tighter emissions standards. Keep a watchful eye out for these as they may be trimmed down (bad) for lower friction and weight. Also beware of pre-2002 CR-Vs, which had a B-series variant. You can also find the K24A2 in the TSX, and it's different enough to need its own paragraph. The TSX mill is a mixed blessing. With a 10.5:1 compression ratio and a 7100-rpm redline, it makes 200 hp (179 hp at the wheels on our dyno). To cope with the higher revs, it has stronger rods and a unique crank. It also happens to have basically the same head we're swapping on here. Sounds great, so why not just transplant the complete TSX engine? One, it's rare and expensive. Two, it comes with throttle-by-wire and an ECU that's not compatible with other K-series-powered vehicles. To make the TSX engine more "swappable," install an RSX Type-S or Civic Si intake manifold and throttle body on it. You'll have to engineer a block-off plate or plug for the EGR port on the TSX head, since it will be exposed with the new intake manifold. So the big question is: Should you buy a TSX engine if you have the chance? If you intend to stick with natural aspiration or light boost, it would be a good choice with its high compression. Additionally, the only other part you'd need to find is a short runner intake manifold. The choice boils down to what you want to do with the engine and what parts you already have.

The head
The RSX Type-S is the only North American source for the K20A2 cylinder head, so you might have to widen your search to find one in the United States. JDM engines are a good alternative. In this case, the engines we're interested in are called K20A and are found in Civic Type-Rs and Integras. They're typically shipped with a transmission (which has a limited-slip diff) and an ECU, all costing between $3,500 and $5,500. The K20A engines are trick, stuffed with pistons that will squeeze an 11.5:1 compression ratio. The cylinder head you'll wind up with is arguably better as well, utilizing longer duration intake and exhaust cams and dual valve springs on both the intake and exhaust sides, no doubt to cope with 8600-rpm blasts. Don't get the K20A2 or K20A confused with the K20A3, which is the base-model RSX engine that you'll be disappointed with if it shows up at your doorstep.

If at all possible, start with two complete engines. You'll miss out on a few important parts if you buy a K24 short block like the timing chain and timing chain cover, unique to the tall-deck K24. The same goes for the K20A2. They're nothing that a costly trip to the parts counter won't fix, but just be aware before you jump at the first K24 block that you see holding the door open at your favorite junkyard.

Mix 'n' match
Let's start at the bottom. Either of the oil pans will work, but the RSX Type-S part is cast aluminum vs. the K24's stamped-steel part. The cast pan is stiffer and braces the pan to the transmission bell housing, making it the better choice. You should also use the full-length windage tray from the K20A2, which will do a better job keeping the oil where it needs to be. The K24 uses a pair of balance shafts cleverly incorporated into the oil pump assembly ("pump holder set" in Honda-speak), but you don't need their extra weight or the friction required to turn them. Hasport recommends ditching the K24 oil pump assembly in favor of the simpler K20A2 part. The oil pump drive chain and tensioners are identical, so take your pick, or get a new one if in doubt about its condition.

You can avoid the machine shop if you don't want the oil-to-water oil cooler that's used on the K20A2. An oil cooler of some kind, however, is a good idea; at least, Honda thought it was on the RSX Type-S. The stock unit has the advantage of being able to warm the oil in cold weather. To plumb the stocker, have the K24 block machined for the coolant return line, which is right above the oil filter boss on the K20A2. Any decent machine shop can do this. You'll also need to use the K20A2 water pump since it has the coolant supply fitting for the oil cooler. Although the factory system serves its purpose, you could do just as well with a sandwich-type oil filter adaptor and a decent air/oil cooler.

On the front of the engine, the K24 timing chain, tensioner, guide and timing chain cover will be used due to the taller deck height. The K20A2 crank pulley is smaller than the K24's to keep the accessory rpm down on the higher-revving engine. Think of it as a free underdrive pulley. On top, use the K24 head gasket, which is sized for the 1mm-larger bore diameter. The head can be bolted on with either set of head bolts; they're identical.

Engine assembly
Start by stripping both engines to short blocks. There's no need to touch any of the rod or main bolts unless new pistons or a rebuild requires it. With a few exceptions, we're tucking a K24 block between all the good parts of the K20A2. As always, arm yourself with a factory service manual for assembly procedures and torque specs. Every thread in the motor is tapped in aluminum, an unforgiving material to a tyrant with a breaker bar. Begin assembly with the bottom end. Install the K20A2 pump holder set on the K24 block. Top it off with the K20A2 oil pump and oil pump drive chain. Next, install the water pump housing, using the K20A2 part if you want to retain the factory oil cooler. Hondabond is used on this joint to make the seal.

Install the K24 cylinder head gasket and lay the new cylinder head in place. It's your choice to reuse the head bolts or the gasket, but again if you're in doubt, or if you have plans for forced induction, buy new parts. Note the head bolt torquing procedure is different between used and new head bolts. Consult the manual for details. Once the head is torqued down, you can install the casting that holds the rockers, followed by the cams and the cam bearing caps. Install the K24 timing chain, tensioner and guide and replace the crank angle sensor wheel, making sure to put it on in the right direction. Cover it all up with the K24 timing chain cover (and more Hondabond to keep the oil in).

Both Hasport and its friends at Hondata have found that K-series engines heat their intake air significantly, causing issues with engine management and power output. Hondata now sells a heatshield intake manifold/cylinder head gasket to replace the factory part. It has measured intake manifold surface temperatures from 15 to 45 degrees Fahrenheit lower than stock with this gasket. If you're going to try one, it will never be easier than right now. Because of the extra deck height, the K20A2 intake manifold support bracket that stretches to the block won't quite reach. We fabricated a 19.7mm tall aluminum spacer to take up the slack. On the cheap without a lathe, you can do something similar with a stack of washers. Don't worry, we won't tell.

All of the bits that still need to go on are straight off of the K20A2, another good reason to avoid the cheap K20A2 cylinder head being used as a jackstand for your friends' del Sol. The one exception is the K24 dipstick, which is longer to reach down the taller block into the pan. Surprisingly, the stock RSX Type-S ECU will make the new K24 run well enough for grocery runs, but hard driving would be unwise. The ECU bases fuel delivery on rpm, manifold pressure, and the amount of air that it knows a K20A2 ingests under those conditions. Since it doesn't know about that extra stroke, it won't add the fuel to go with it. The timing is also optimized for 11.5:1 compression, and can now be advanced significantly for the low 9.5:1 or 9.7:1. Conveniently, Hondata offers a modified ECU the way we like 'em, plug-and-play. Just like on the Sci-Fi channel, your brain will get modified and shipped back with a USB connector on the back, along with some software that will let you tune the Honda ECU yourself. It'll also supply an assortment of base fuel and spark maps to get you started. No extra wiring, no extra sensors, no stress headaches. Well, until you start tuning it.

Free power
Sometimes we run across a mod that's so easy and effective, we wonder what kind of cost-management weenie would nix the idea. This is one of them. If they'd shipped the RSX Type-S with our hybrid, it would've been a fierce competitor, even against the turbocharged clan (beat by a Dodge...ouch). Our 2.4-liter mustered 30 lb-ft more torque across the rev range, leading to a power increase between 15 and 30 hp all the way from 2000 rpm to redline. Is this free power? Basically. The added displacement is good for more than a 25-percent increase in torque throughout the rev range, with no loss of driveability. The hybrid can even drink the cheap gas, thanks to the lower compression ratio. True, you can't impress yourself with an 8000-rpm redline, but that's a small price to pay for going faster. Using the K24 block not only adds torque, but the hybrid's lazy 9.6:1 compression ratio cries out for supernatural aspiration. And remember, it doesn't take much boost to make insane power with 2.4 liters. We like this mod because you get great results from stock parts. Especially if you already have an RSX Type-S or anything else with a K20A2 stuffed into it, you'll be hard pressed to find another bolt-on that nets as much power for the price. So the adage is correct; there is no replacement for displacement. We've just combined it with a dose of modern engineering to prove it once and for all.


Sources
Hasport Performance, Inc
(602) 470-0065
www.hasport.com Hondata, Inc
(310) 782-8278
www.hondata.co
 

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Discussion Starter · #4 ·
Thank's, massive write up.

I'm from Europe, and that CRV which will be separated in parts have 2.0 L engine as all other in Europe, I did not see the 2,4 L engines in CRV here.

Is it worth to did that swap? I have now the B20/B16 engine in my LS.
 

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root79 said:
Thank's, massive write up.

I'm from Europe, and that CRV which will be separated in parts have 2.0 L engine as all other in Europe, I did not see the 2,4 L engines in CRV here.

Is it worth to did that swap? I have now the B20/B16 engine in my LS.
REad the next post :)
 

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Discussion Starter · #6 ·
That mean that in future there will be no problems to change the cylinder head from K20 which goes to Civic Type-R(we do not have the RSX in Europe).

Wery big write up, English is not my native language thats why it will take the time to read it.
 

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root79 said:
That mean that in future there will be no problems to change the cylinder head from K20 which goes to Civic Type-R(we do not have the RSX in Europe).

Wery big write up, English is not my native language thats why it will take the time to read it.
What is your native language?

I can also speak greek, french :p
 

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Discussion Starter · #8 ·
Latvian. Latvia is in Eastern Europe near Baltic sea. There are three sister countrys like Estonia, Latvia, Lithuania. My friend in Lithuania going to instal the K20 from CTR into Integra type-R 1999 year.

So, is it worth to do that? I can get that 2002 CRV K engine with everything buy 1500$
 

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root79 said:
Latvian. Latvia is in Eastern Europe near Baltic sea. There are three sister countrys like Estonia, Latvia, Lithuania. My friend in Lithuania going to instal the K20 from CTR into Integra type-R 1999 year.

So, is it worth to do that? I can get that 2002 CRV K engine with everything buy 1500$
I am not sure about the exact engine... I have to do research... Most likely no. You would be better off with a b series engine.

YOu cannot use the CRV transmission. Therefore you would need a Civic Ep3 transmission.

You could use the CRV block+ CTR head and tranny but that would be expensive for you to get all these parts.... like mounts.... wires....

Here in the USA, it is easier because there are 400,000 k24a made every year. The reason why I like them is because they have torque... The CRV engine you are talking about is basically a CIVIC Si (not CTR)... too much trouble in my opinion...

Get a k20a from Japan, or a k20a2 from the CTR or go B series or H22a
 

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Nikkos..want my K24 dammit...lol..excellent info there homie. i think i will add a K20 head sometime next year.

so in order for me to rev say to 8K i would need pistons and rods correct. just like b20vtec. i mean i know you should sleeve but iknow a lot of people reving a b20vtec to 8k safely

also im going to add pistons and rods anyways...hmmmm...cant wait to purchase my motor...
 

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my CRV I-VTEC is now turbocharged running on safe boost 0.4bar.....




i give out some detail about my car:

Is a SUV

Car Model: Honda CRV I-VTEC Model 2003

Engine: K20A3 2.0 Liter engine

using a 2mm metal gasket

internal parts of engine are stock standard

used with endless 10-40 semi synthetic motor oil

engine decoration spoon style

using HKS Ball-bearing GT2530 Turbocharge with Apexi funnel filter,Sard

R2D2 BOV

Boost Controlled by Apexi AVCR

Engine management by Greddy E-manage

Gearbox 4-speed auto with final ratio filled with RedLine ATF transmission oil

Anyway my turbo is without a intercooler running on safe boost 0.4bar i looking forward for a intercooler real soon.

after intercooler it will be going for 0.6bar of boost it very powerful in o.4bar....

Want to know more you are welcome to reply at this forum hehe.....
 
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