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Discussion Starter · #1 ·
k24a2 block/k20a-r head

well from doing a little research, ive been trying to figure out whats the ultimate k-series frankenstein or head swap etc.....from what ive read i see the best thing to do so far is (imo) to get a k24a2 block and mate it with a k20a-r head, now i dont know if its possible but i was thinking using dc5-r parts on the k24 like intake manifold, pistons, throttle body, header etc....cant it be possible ??? and is it worth it ???

h22 block/k20a-r head

i saw a post on this here, now this i couldnt believe, but i dont understand why people would do this instead of just using a k24a2 block, more displacement first of all....but one thing i did notice was it will benefit people with preludes and shit like that....i think the post im talking about, braun was using a k20a2 head not an r head buy you get the point, for those of you who are interested in this, from what i read you have to change from chain drive to belt drive obviously...but one thing i wanted to ask was if they used a k24 crank in the h22 block, but i dont see why they would do this instead of just using a k24 block ???

k24a2 block/f20c head

havent read anything on this but is it possible and if it is would it be a shit load of custom work thats not even worth it ???

thanx im very new to k-series, but i want to build a sick k-series

one more question, what flows better f20c head or k20a-r head ???
 

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The K24a2 (TSX) head has been shown to flow just as good as the K20a (RSX-R) head. The only thing about the K24a2 that does not flow well is the intake mani and throttle body. Replace these and you will have no need for your ultimate k series frankenstein. You just can't rev all that high because of the 99mm stroke. Thats when you redo the internals (crank, rods, pistons), which will mostlikely be aftermarket.

Then you really have the ultimate 2.3L K series :dance:
 

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You should really read some more of these posts though beacuse I swear I have heard this same question asked about 1,000,000,000,000,000,000,000 times...

Well maybe not that many but it has been asked already a few times.
 

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Discussion Starter · #4 ·
so just the intake manifold, throttle body and compression balanced crank and rods is what makes the R an R, im pretty sure the r is ported to, so how will the k20-r flow just the same as a k24 head ??? are the k20-r parts interchangeable like pistons and rods, no right....also what about camshafts, valvetrain, ???

what about the other frankenstiens ???
 

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I wish people would stop saying that you can't rev a 99mm stroke. But what do I know.
 

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k20ahondas said:
I wish people would stop saying that you can't rev a 99mm stroke. But what do I know.
Other then a decked block and longer titanium rods and a balanced rotating assembly...what else do you need to rev a 99mm crank to 10000rpm?
 

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k20ahondas said:
I wish people would stop saying that you can't rev a 99mm stroke. But what do I know.
k20ahondas said:
longer than 5.9?
Well I said with the stock bottom end I wouldn't rev it high. But I really don't have all that much experience/knoledge, really.

So what are you saying, you rev to 8-9k on a stock block?
Or you just need longer rods to rev up higher?
 

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CTRjesse said:
so just the intake manifold, throttle body and compression balanced crank and rods is what makes the R an R, im pretty sure the r is ported to, so how will the k20-r flow just the same as a k24 head ??? are the k20-r parts interchangeable like pistons and rods, no right....also what about camshafts, valvetrain, ???

what about the other frankenstiens ???
I'm not sure what a compression balanced crank is but, I don't think the R is ported. from what I have heard and read the ports on the K-series are plently big and do not need porting. The cams and valvetrain are interchangable so that would make a big difference. The pistons on the TSX motor are higher than the other K24's but still not as high as the K20a. Pistons and rods I don't think are interchangable but don't quote me on that one. I think the 99mm crank is strong enough but when you rev it up with the stock rods and pistons the piston speed is not to friendly to the sidewalls...
 

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k20ahondas said:
I wish people would stop saying that you can't rev a 99mm stroke. But what do I know.
Ahh don't tease us like that man! Are you using a 99mm crank and stock length (for K24) rods? And what do your bearings look like when you teardown?
 

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Maybe Norris is using a stroked K20A. I heard that a guy on Club RSX is getting an N/A motor built that is a 2.3litre stroked K20A.
I'd be interested in wheather you have a wider big end machined into the crank aswell as the longer stroke to try and resolve the big end issues. I've heard a few people talking about machining the crank to fit a custom rod with a wider B.E.
 

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there's nothing wrong with running 10k rpms with 99mm cranks. I have personally seen more than 99mm reving to 9500 with other honda motors. Look at skunk for example.
 

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Every engine builder has there own ideas. I personally like shorter rods with very high pistons speeds. That's why I chose the k20 block vs the k24. I have seen a 7" rod for a honda motor and that thing just looks really weird to me.
 

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Dc5itracer said:
Edo in another post suggested a 2.0l crank in the k24 and a 6.250" rod with custom pistons with a slight overbore :up: itll be around 2.2-2.3L
Totally different application. We build motors in different combinations to focus or isolate for a certain goal.

Norris' combo is bitchin for all-motor drag. All else equal when comparing rods - a short connecting rod will weigh less than the long c-rod. High piston speeds are what you want in this application because it is a time to distance 1/4 mile race. We want most available torque and power on tap as soon as possible. This combination of short rod, good stroke in a short block works very well for the intended application.

Alternately, long rod motors are traditionally slated for circuit, road-race and in general - high-strung, smoothly balanced, high-rpm motors that need to run up there constantly for long periods of time such as endurance races. The particular long rod application you quoted me, is intended for a motor to isolate our IPS-KT1 and IPS-KT2 cams. They are a cunningham regular (non-ultralight) forged steel rod that isn't particularly light. Because it is a Honda VTEC turbo application, we want rpm capability and no strength worries. This is where it's okay to have the beefy rods. Why the long rod for this test? Well, we maxed out the rpm potential of the stock internals (86mm crank w/narrow 0.780" rod journal width, K20 block, 5.473" stock rod) and turbo (GT3071R-WG .86 AR) we chose before we could conclude testing the high speed lobes of our turbo cams. By using the 86mm crank (widened to 0.935", race-prepped) in a sleeved K24 block, the piston speeds will be kept down (not running the K24 99mm crank) and the 6.250" long rod (necessary for the K24 taller deck: 9.120") will minimize side-loading (thanks for reminding me rochesterricer!). This is just a rod/stroke combination I've always wanted to try. It has a 1.85:1 r/s ratio and this combo will not have the rpm ceiling we had with the stock stuff. The new T3/T67 H.O. will alleviate the turbo restriction we had previously. For us, this is just about building motors that will help provide insight in releasing the best product we can.

-Ron
 

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k20ahondas said:
I wish people would stop saying that you can't rev a 99mm stroke. But what do I know.
Well, it is partially true. The real question to ask is how LONG you want it to rev that high. Edo did a pretty decent job of explaining it.

One thing you guys will want to keep in mind when you are deciding on your build; rod length will not solve revability issues. It only affects side loading, not piston speeds.
 

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Thanks for including supporting details I overlooked with my previous post. It's one of those concepts where it's easy to take for granted and forget to mention.

I went back and edited my post to include more details. Kinda messy with parentheses, but I didn't want to rewrite it completely.

-Ron
 
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