2.0lhatchback

hello all,
new to honda-tech but not too new to hondas.
about to buy my first K series, want to fully build this beast.
few questions i have are:
can you get the same amount of power fully building a K20a3 as you can with an A2 or K20a?
(my horsepower goals are 235-250.)
also:
what would be the best possible internal parts (pistons, rods, cams and what stage cams, valvetrain and retainers.)?
please help as i am anxious to start buying parts.
thank you!

Search-first

The variable valve timing system is gonna hold you back a lot compared to the other ivtec systems which are a little like the more traditional vtec systems with the timing adjustments and load sensing fetures. I've never seen a powerful k20a3, its pretty much the D series of the K series world. Most people swap it out for the better K20's or turbo the A3.

k20coupe

Don't do it just a k24a2 and go from there the head is as good as the a2 head and u goign to get the tq try to get the 06 model it comes with the best oem cam combo for an all Motor setup

2.0lhatchback

thats what i heard about the A3 with the whole valve timing arrangment, is there any way to swap just the valve timing? or maybe do a k20a3 with an a2 head?
i might not even be getting an A3 at all i havent heard back from the people im buying it from but something is telling me its the k20a3. thanks for the advice guys i appreciate it.

dkid15

If you want to do something on the cheap use a CRV motor(k24a1) get high comp pistons, new rods and bearings, and an agressive set of cams you can make over 250whp on a nice tune. Check out asp's build on k20a.org

k20coupe

Asp makes over 300 in their a1 but it's a race motor

projectTeG

instead of swapping out the entire engine, why not just change to the a2,z1,z3 head?

2.0lhatchback

im not worried about the money, my hatch will be professionally built, not cheapin out on this, i need a strong motor throughout. and projecteg, i can just put a new head on it and get the same power as an a2, z1, or z3? thats probably the route im going to go then cuz im getting a great deal on this motor so i dont want to keep lookin around, its going to be fully built anyways so the more i can save on the motor, the faster i can put the good stuff in.
are crower products what i should be looking into? i head they are real aggresive head wise, and ill probably go with wiseco 12 or 13:1 pistons...
opinions?

k20coupe

Dude get the k24a2 and go from there don't waste ur money on a k20 build

98vtec

best possible? i hope you have deep pockets.

https://honda-tech.com/forums/k-series-153/300whp-ips-k24a-93-octane-making-impossible-possible-2290806/

k20coupe

Ips$$$$$$$$$

2.0lhatchback

ok, well money is an issue, obviously im not wealthy but i want it done right, so i am willing to pay more for good parts and good work.
and 300whp would be very nice specially on 93 octane but my power goals are 245-250hp. thanks for sending that thread link though, definatly a good article.

00Red_SiR

From what I recall, there was nothing good about the K20a3 motor and it was not considered a good building block to start with. The A2 motor was where to start. Better rods, IVTEC, head and other things if memory serves.

2.0lhatchback

im not too concearned with the bottom end of the a3, read that its the same bore/stroke/etc as other k series, and im going to be upping the compression to a 12.5 or 13:1, mostly concerned with the head, and the vtec system. but if i can put an a2,z1, or z3 head on it and have the same vtec system/head power as those series of engine i'll go that route

kprocivic

you can use the rsx head on the a3 but you wont see a2 numbers. a3 doesnt have the compression or the 6spd tranny, without the tranny you will fall out of vtec after shifting. your best bet is to just turbo the a3 it will handle around 300whp until the crank will want to walk. even with upping the compression you would need a 6spd tranny and and the corresponding ecu. like i said it would be cheaper just to turbo and call it a day.

2.0lhatchback

not a fan of turbo. used to be, but im thinking NA is better for what i want. and i'll be putting a type s tranny in it

kprocivic

well getting 230 whp NA out of the a3 aint gonna happen. no matter what head you have. also if your doing all the work yourself for the head and tranny swap then it might be worth it. but if you still have to pay for labor you might want to look into either forced induction or a new motor.

2.0lhatchback

im going to be doing a full build. just so were on the same level. gold eagle sleeve kit, wiseco 12.5 or 13:1 compression pistons, crower maxi lite rods, (still looking at cranks.) and a full crower internal head port and polished with TWM 54mm ITB's. pretty sure i can make 230hp, probably 245-260hp on race fuel. if im anywhere close to wrong on that please let me know now.

k20coupe

U don't need to get all crazy with the cr ratio stock bottom end k's make about 230 to 250 with bolt ons and cams

kprocivic

lol im done here. obviously you have deep pockets more power to you. you will have a 5 thousand dollar a3 that will get killed by turbo a3's. i guess you looking for some kind of satisfaction building the a3 that much. you might hit 210-220hp for all that you plan on doing but realize with any other motor your looking at 260hp and up. the a3 has its limits plan on getting a typ s oil pump also. buy a k24a1 and throw a type s head on there tune with kpro and other supporting boltons and your looking at 210-220whp with gobs of torque. just think of it this way your starting off with the worst possible k20 for NA, i think youll be alright though cause it sounds like your down to throw at least 5-8geez in this build.

kprocivic

not the a3. only the a2,z1,z3,a etc.

k20coupe

Look just check k20a.org in the all motor section

2.0lhatchback

im not into the k20a3, and i know its the weaker of the kseries, which is exactly why i started this thread. (to see what i can do to make it a stronger motor) and 5-8k on this motor would be nice, i hope i can keep it around there. its not that my pockets are deep, its that id rather spend lets say 10k up front and know that i have a more reliable motor than if i were to try to do a 250-260 NA build for only 3k. it just doesn't make sense that if you up the compression, sleeve it, and put an a2,z1 or z3 head on it, why it wouldnt be closer to that of a stock a2, z1, z3 vtec wise... not tryin to be an ***, and trust me, i dont know alot, but i know enough, but would like other peoples opinions/advice seeing as how maybe they had these questions and had the chance to see what to do about it.

kprocivic

yeah i know your not trying to be an *** good luck with your build. like the other guy said try k20a.com, i-vtec.net, ephatch.com, or clubrsx.com. and to answer your question the a3 block is slighty different than the others it does not have oil squirters in the block to keep things cool. and im not trying to shoot you down but it takes more than throwing an a2 head on the a3 block to be on par with the a2. i try to look out for people who are misinformed with the a3 so sorry if i come off to be a dick, just seems like to much work time and money for the return you get. hopefully someone else will chime in and help you out peace.

206 EH2

sounds like a3's are piles, which is why the dude is trying to sell it to you for so cheap.

it is a k series, but barely.
maybe you should look for a different powerplant bro.
this a3 sounds like more trouble than its worth.
just do a b20 vtec n/a build. :D