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^^^imp:

 
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K24 block --> Fully Built --> 1500?
K20a head --> Fully Built --> 2000?
K20a ECU --> Hondata Flash --> ???? (8500 rpm redline..yumm)
K20a tranny --> 6 Speed manual --> ???? (LSD?)
Custom Turbo --> 4000??
K20a axles.. or K24 axles.. dunno how that will work (I'm not a suspension king)

Ok - if you are going to boost you may want to rethink some of your choices from your above list. The k24 block is fine. Putting the dc5r head on it is not worth it in the long run for FI because when boosting you want short duration and high lift cams - the dc5r has long duration and has the same lift as the rsx-s.

Next you will not run the k20a ecu and boost - it just wont fly. Yes the k20a has a lsd stock but have been known to let go under large power and you would be better off with a quaife lsd (life time warranty).

Custom turbo - yes you can but with that custom turbo you will need custom tuning = $$$ you would probably be better off looking up cybernation and going from there. They have worked out all of the tuning issues related to boost and the k20.

You would use the axels from what ever tranny you end up choosing. Cheaper to use Type-s tranny and a lot easier to find.

Kiss the 8500rpm red line good bye if you use the k24 block and keep the k24 crank - the 99mm of stroke would cause your engine to grenade at 8500 rpm - even fully built i would be scared to rev that high - not to mention with boost on top of that. If you keep the 99mm stroke you wouldnt need to rev that high anyways - you would be making monster tq/hp and could stop reving around 7800 rpm and save the engine to rev another day !!

Crower is finalizing their k-series cams for boost etc - look into those cams as they will have the right lift/duration that a boost engine likes!

Lates

 
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Thanks for the info.. I've been wondering.. If I can't use the K20a ecu and boost what ecu can I use, and boost.

 
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if you go with a cybernation turbo kit they have worked out their own ecu tuning piggy back that compliments the k20a2 ecu...

some people have made the greddy e-manage work

and others are trying the hondata k-pro programable ecu - no matter what option you take at this point all will take some time to get all the kinks ironed out - but i think cybernation is very close to having the tuning side 100% worked out

 
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Thanks for the info, buddy.

 
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no probs

 
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Just a couple of thoughts...

First off, I'm not a turbo guy nor am I a k20 guy, I'm looking at the 200whp from a daily driven D17, got a block and just building as I get money, so don't ask questions yet.

Second, I've got a lot of freinds with turbo's on their Honda motors... they all say the same thing, they had cams, put the stock one and their systems ran better.

Third, I know one guy running a B20 that doesn't believe in VTEC and boost combined. He thinks, and I kind of agree, that VTEC on Honda's is for N/A. His theory, in short, is that a turbo makes torque, mad torque if done right, what in world is Vtec (which is ment for highend horse) is going to help? Now he does have a set of custom cams, which I know goes agianst number 2. I won't get into his reasoning, but I assure you it is VERY sound as he works in the R&D department of Honda and we have discussed many engineering theories. What you want is an under squared motor to make the torque to push a bigger turbo. VTEC will not help in this case. In short, save money and just keep the whole K24 engine set up and boost the crap out of it, it's got lowwer compression than the swapped K20A heads too.

 
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Jrfish007: i agree with you that honda motors are designed with N/A in mind and not boost. I personally would not boost my k20a2 but that is just me - obviously FI will give you the most gains at the least amount of cost.

Secondly - i would say that above all else - tuning is what makes or breaks a motor in the end and your friends with cams that switched back to stock probably could have used better tuning for those cams.

Yes the k24 has lower compression and is ideal for a turbo setup but reving a long stroke engine too high is bad - and isnt really needed on that engine.

In the end you need to lay out your goals and you have to pick N/A or Boost because they way you build your engine is fundamentally different down either path.

Here is a rough idea of the N/a engine i am going to build:

k20a2 head
k24 block sleeved and bored to 89mm
04' s2000 crank 90.7mm stroke
159mm custom rods

that combo will give a 2.3L engine with a r/s ratio of 1.75 that will be able to rev and see significant tq increase as well....of course it comes down to tuning all of those pieces!!

 
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Yes, I'll agree tuning is a must and if you don't have it, you don't have a motor or car. The day's of simply building a motor and starting it up and running it went out with carbs, and even the topend guy's with carbs are always on dynos adjusting this and that.

The whole idea behindthe boosted B20 is not high revs. With higher revs your volumetirc efficency goes down which is countering you turbo system. With a turbo, you want as high of volumetric effeciency as posible and you usually stay around 95% untill about 5500 rpms (that's just a rule of thumb that been generalized for all the little rev happy 4 bangers out there) after that it drops... it drops fast too. That's the reason for loss of torque. Remeber torque is what is being eatn buy your compressor on your turbo. The air being pushed out of the cylinder that is pushing the compressor is being pushed by the torque of the motor. So, long stroke with low rev and big turbo = power, but not a good power band which is bad for track but good for straight line racing like he wants.

The S2000 crank is a great idea, I never looked into that, but if it fits that's one heck of a good mod. With you're boring you should see a good tq increase too. That's probably one of the best N/A set up's I've seen for a Honda, great thinking!!!! What's the K24's crank stroke? and how high are it's pistons compared to that setup though? My only worry would be about slamming the pistons into the valves. What about compression, I don't think it's going to go above 11.5, but if does, say good bye to pump gas (unless you run your ignition so retarded it almost stalls and makes no power). Just a couple of thoughts, I really have gotten into the K24, so I don't know much about their exact numbers, but that set up sounds bad azz if it works. Good luck with that.

 
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the stock k24 crank is 99mm of stroke

the deck height is 19.7mm taller than the k20 block and the k20 has 139mm rods so it should fit the new rods...

the s2000 crank should be a direct drop in option (both are chain driven)

 
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Ahhh... so you're destroking the motor.... and boring it. The destroke will take torque away, but the boring should give it back. But that destroking idea is going to give a HUGE power band up high, so you can go up to 8500 rpms??? I gues i could calculate the piston velocity to find out what would should redline at if you haven't. Sounds like a well thought out monster.

 
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should be able to rev to 9k easily with forged internals

ya if you dont mind calculating the piston speeds - i have not done that yet...

 
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I'll work on Sunday, I'm at work right now and I think boss is here... lol, I'll see what i can do

 
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I don't really wanna rev my engine to 8500 rpms.. I want to cut off around 7.. and a fully built bottom end k24 should be able to hold 7000.. If it can't though let me know.. I'd like to drive it more than once

 
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Damn Jrfish007 and arctic-k20 seem to know there ****. I totally agree k24 at high end equal grenade if not done right. Brian G has said it himself as well.

 
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If you plan on doing the swap.
REALLY PLAN IT OUT.
I am almost done my K20A2 with Cybernation Stage 1 turbo and it is nothing but modifications PLUS ...
You need to take with Brian at HASport about wiring problems with the swap and the turbo set up.
Heres the progress so far:
http://www.7thgencivic.com/forums/sh...d.php?t=154125

 
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Alright... Actually once I thought about it, you have the same stroke as the S2000 you're pulling the crank off, so you'll have the same piston velocity as that S2000, which means you should have the same "redline." If you want to calculate piston velocity, follow the example below (I'll use you your engine make)

take your stroke, 90.9 mm
double it -- 181.8 mm
mulitply it by your highest RPM desired (we'll say 8500 RPM)--
181.8x8500 = 1,545,300 (that your piston velocity)
Now that number means nothing to me because it's in mm per minute.
So if you mulitply that number by .000037, it will become MPH (a much easier number to understand)

so 1,545,300 x .000037 = 57.6 MPR

Now that number means a little more to me and remeber that is the AVERAGE piston velocity, it can get going to about 150 MPH when the flame wall of the combustion chamber hit it during the power stroke.

57.6 MPH is not bad for an engine, but it is recommended in text that if you excede 50 MPH, the every internal peice be spun balanced and blue printed. They also recommened taking the engine appart every 25K miles to recheck balancing, but with Honda's "floating" pistons, I don't think it is needed.

With the crank already desined for that speed (becasue it came from an S2000) you need not worry about that, maybe have it spun balanced or something just to check it out. The rods you said where costum, so take them to a second shop just to make sure they are balanced too. The pistons should be symteric as to make sure they are balanced at high speeds and don't become unstable. But with the set up you say, I don't think you would have a problem with 8500 RPM. Basically find out what the S2000's redline is and that's you're red line, assuming the heads can take it. I know Honda just changed the redline for the S2000, I think it is now 8500 or 8200, some where in there.

By the way, don't go above 60 MPH with a piston velocity. 55 can be pushing it, so you may want to stay at 8000 RPM just to be safe, you're going to have lots tied up in it and don't want to get to rev happy and blow it.

 
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after doing some more math - the longest rod that can fit in the k24 using the s2000 crank without altering the piston pin placement or compression height is 155.9mm if anybody cares

 
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I think that may lower your compression, you may want to mill the head a little to compensate. You're lower the bottom of the piston by about 4mm now, so that should take a tiny bit of compresion out, I think. Personally I would go for high compresion pistons because that will give you a top end nobody around will be able to touch... except me when I get done.

And yeah, I care, that is one of the badest azz set up's I've heard for a Honda motor, I want to see it happen.

 
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the 04' s2000 redline has been lowered to 8000rpm vs 03's 9000 rpm

the 03' had a piston speed of 4960ft/min and the 04' now has a piston speed of 4761ft/min

for reference F1 racing engines avg around 26m/s (metres/sec) or around 5100ft/min - that is avg - their peak speed is up to 41m/s or 8200ft/min = SCARY

 
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goood LUCK dude.. i support u 100%.. kill that GTP

 
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F1 racing has a small advantage over us... like millions and millions of dollars and the best engineers in the world

To bad our little D17 only goes to 4340 ft/min... or at least most peoples, like artic-k20, I intend on destroking the motor to achieve a higher RPM, although I will probably bump my piston velocity up to 4600 ft/min. Hopefully resulst in a redline for D17 around 8300 RPM.... BUAHAHAHAH

 
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^^^^ With high compression to keep volumetric efficency up....

BUAHAHAHAH

 
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that is 1 of the key things that i get foggy on - compression height and the comrpession ratio...

im unclear on how much room you have to change the compression height and still maintain a good compression ratio...??

 
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You guys are scaring me.. I never wanted to even think of compression ratios when I had a motor built. I just wanted to run something that put down some serious horsepower when needed..

I'm still gonna do the swap though

 
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Okay.... compression height to compression ratio...

The compression ratio is the ratio of swept (total) displaced volume divided by the compressed volume. ~ howstuffworks.com

If I remember right, compression hieght is the top number, or swept displacement.

So, if I remember right, you have lost 9mm from the crank and 19.something from the heads for a total of 28mm. But you got some of that back with longer rods, what 16mm??? The problem hear is that someone needs to find the volume of the dome of the the K20 heads (with all valves closed of course). If you get that, I'll read up on the actual calculatins of the compresion ratio.

Ricerocker ~ you just want to swap, you don't need to worry about that stuff. Arctic-k20 is destroking his motor and swaping a new set of heads on to it. He could simply do it with stock pistons and stuff, but if you're going to do it, why not do it all right and re-engineer the whole thing. I'm doing the same thing with a D17, although mine is a little easier because I'm not swapping heads and am looking to run a real high compresion, 12:1.

 
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Hmm.. I see your point..

 
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whoa

 
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you could do a swap, but then you wouldnt be holding up to what you previously said about building ur d17 there buddy...

(I'll run you next year when MY D17 is built and turbo...)

 
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one thing that sounds kinda iffy is the Hondata K-Pro and the 2.4L displacement of the K24 block. k24 is the stroked version of the k20 obviously, so would it be wise to run 2.4L of stroked displacement at the 8500rpm redline? i read somewhere that the inertia forces of hte pistons with that high of a displacement would be kind of dangerous, unless you were running really light internals...

i might be wrong but it may be something to look at...

im sure the valvetrain would be built to handle much more than 8500 rpm, but dont forget the bottom end!