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Discussion Starter · #21 ·
So glad you turned me on to Toda, their stuff looks perfect. I haven't seen anyone run their products and I see why, Their piston/rod kit alone almost as much as my Del Sol. I definitely plan on using strictly Toda now if possible.

I noticed almost all of the parts listed on the Toda website are labeled for the k20 and not k24. Am I correct that almost all important parts (camshafts, pistons, rods, fly wheel etc) for the k20/24 are interchangeable?
Here's their parts cataloge
 

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Discussion Starter · #23 · (Edited)
Yeah I guess since one is 2.0 and one is 2.5 L that wouldn't quite work would it lol 😔

Edit:looked up the diameter of both k24 and k20 piston and I'm surprised to find they're only 1mm difference in diameter. I thought there would be a bigger discrepancy!
 

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Arouse the DAMPFHAMMER!
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I noticed almost all of the parts listed on the Toda website are labeled for the k20 and not k24.
They developed all those parts for the K20 for reason. It's racing what they had in focus. The 99 mm stroke engine is not the best choice for racing. They had the famos 2 Liter classes in focus, there are almost no competitive classes above that where the 2.4 Liter would be an option. There are much better engines in that area like the Volvo B234F, which has only an 80 mm stroke and a 90 mm bore, but is able to be bored up to 96 mm and have a 77 mm crank also available. The head was designed by Porsche. I've developed a package for that engine, it is easy to get over the 300 hp mark with it in a very reliable and durable setup, which the K24 never is in endurance racing terms.

Here's their parts cataloge
I wouldn't rely on TODA Racing USA. I observed issues with their cams, which are definitely not from TODA JPN, as they worn out too early. I buy only at TODA Racing JPN if I buy from TODA. I don't know how those two do business together and if they build things in licence or if they just sell original parts. But my observation made my decision clear. I would recommend you to clarify this first. May I am wrong, may some are built in the US and some in JPN. Clarification would be good anyway.

Pistons and rods are certainly not interchangeable between k20 and k24
The only thing what can be used is their 87 mm bore piston if it has also the 30 mm deck height, a customized rod could accommodate differences to 0.0 mm deck height.
 

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Discussion Starter · #25 · (Edited)
I've been thinking a lot about my engine. It has kind of been a toss up of doing a full Toda k20 which will be very expensive and harder to come by parts but I will have a satisfying full Japanese engine which is very attractive to me in a way. The other idea is a k24 block/ k20 head. Basically a rip off of Mike Kojima build on youtube minus the magic coating he puts on.

parts used:
stock crank
K1 rods with ARP 2000 bolts
JE FSR strut type pistons (I'll use a more aggressive compression than his build)
King xp bearings
4 piston modded oil pump
K Tuned chain tensions

Drag Cartel CNC ported head with Supertech valves and springs
Drag Cartel cams
RRC manifold
K tuned throttle body

I may have the money to do both builds but being somewhat frugal and knowing the 24/20 is going to put out the same or more power at a fraction of the cost of a full Toda 20, I will probably be going with the American parts. No one will care what's under the hood at the track after all (or will they idk?) and the American parts are of course respectable in their own right. Let me me know what you think of that set up. I'm hoping I can find all these parts in a timely matter but with Covid and such they're probably OOS everywhere.

Thanks again everyone for putting up with all of my BS. As you can see this has somewhat become an online journal for this build in a way. Fingers crossed that I have some parts in my next post and not just more words. ;) It's a big help to me having some back and forth with real people than just thinking to myself about it. I try to talk engine and suspension to my Waifu pillow but I don't get a lot of feed back. 😔
 

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Arouse the DAMPFHAMMER!
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...knowing the 24/20 is going to put out the same or more power at a fraction of the cost of a full Toda 20...
I would decide that along the application use.
  • Street and WW = Frankenstein
  • Race (endurance, hill climb, slalom) = K20
For me the K20 makes more sense, but if you have time and money doing your stuff yourself the Frankenstein can be revved like the K20 ;).
 

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Ive kicked around the numbers and still want to drop in a k20 crank into the 2.4 block. Long rod and punched out to 89mm bore. Would be a happy revver. Stable at rpm too.
 

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Arouse the DAMPFHAMMER!
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Ive kicked around the numbers and still want to drop in a k20 crank into the 2.4 block. Long rod and punched out to 89mm bore. Would be a happy revver. Stable at rpm too.
Definitely a hot rod or crank 😉. Still a costly solution to get the higher revving capability. The rod bolts aren't the winner with this approach, it is the side load, which makes it more efficient when engine speed rises. That's more difficult to calculate, just have assumptions, no verified calculation model on that. The rod length increases from 139 to 158 mm = custom rods plus a sleeved block for that 2140 ccm engine. The head would also like it, less shrouding and if needed bigger valves for the better feed at those speedings. I know none who did this. Seems like a dream of many, but not a realized built. Are you going to do it?
 

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Discussion Starter · #29 · (Edited)
Lotus, check it out man. Toda has a k24 piston/rod kit.

Looks like full Toda still may be on :unsure: Toda franken build can be a reality.

Nevermind that idea I, emailed them and they won't ship strait from Japan and recommended that Misano website. They were super polite though, and I can say I got in touch with a Japanese TODA sales rep so that's neat in a way! I'm just hesitant now that you said that the USA site may have sketchy cams. I mean if the Japanese rep said they're legit they should be good to go? Maybe I can email the USA TODA "Misano" team and see if they can get the K24 parts imported since at least we know they exist.

I'm running numbers in my head on that Misano TODA USA site and the full TODA kit is going to run me something like 15-20 thousand and That's all motor. You can probably see why i'm kicking that can!

I really want the sport injection kit though if I want to be a purist. I will have to get that done at a shop no way I'm doing full sports injection individual throttles my first motor build... Would be wicked though no? It might be worth finding a good shop. ;)

I would imagine I can run a franken build MUCH cheaper. My Del Sol is nice but is it 15-20K motor nice? It has a dent lol.



Imagine opening the hood to this though!



edit: sorry mods for the constant edits lol I do this in the middle of the night sometimes. I need to start writing this stuff in drafts.
 

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Discussion Starter · #30 · (Edited)
Well I just bought a 04-08 k24a2 TSX block! I'm going to start a franken build weather I do the TODA build or not. LETS GOOO! 😆

edit: got a crank too

edit 2: DC CNC ported head with supertech valves purchased 🤫
 

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I don't see any reason why another brand of lower end components wouldn't work very well.

Low expansion alloy pistons for stock like driveability, after my own research into it and reviews from others I have a brand I will go with. Lightweight rods that will accompany good rod bolts or studs. All about keeping it simple. Simple to build, maintain. Will still make good power and you will be able to be competitive.

Lotus, yes that's a pipe dream that I have. I would love to have a 9500rpm engine that will last a long time between being refreshed. I know Colin had an engine that IPS made wayy back when. Was super trick and ran an f series crank I believe. Never was ran if I recall correctly. Truthfully I'd be happy at an 87.5 mm bore and take the displacement hit for orm sleeves and the ease of use on that.
 

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Discussion Starter · #32 · (Edited)
Small update: Drag Cartel emailed me and said about two months for the k20 ported head! I bought the "endurance" model which I think is just .5 mm increase but should be plenty! I'm very happy with DC as my choice, they seem like a great company.

I'm going with Carrillo 11:0.1 pistons and rods. I noticed most pistons and rods are made in china and finished in the states, so Carrillo being made in America fully sounded good to me.

In the mean time I will try to get the block on a stand and hopefully get going pretty soon on the bottom end. The block is stuck in California it seems unfortunately although it still says it will be here tomorrow still somehow, kind of doubt that though.

I also can change the worn out clutch in my b16 transmission if I get bored.

I'm no expert but judging from all I've been reading and watching, this should produce over 300 hp. I could be very wrong though.
 

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Arouse the DAMPFHAMMER!
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I bought the "endurance" model which I think is just .5 mm increase but should be plenty! I'm very happy with DC as my choice, they seem like a great company.
You mean that one: K-Series STREET / STRIP CNC HEAD & OG CAMSHAFT Combo Special 47 – dragcartel?

'm going with Carrillo 11:0.1 pistons and rods.
Why so low for 300 whp? Do we still talk about an NA engine setup?

I noticed most pistons and rods are made in china and finished in the states, so Carrillo being made in America fully sounded good to me.
CP Carrillo was overtaken by Pankl (Austria, Kapfenberg) in 2015, were they increased their share from 70 to 100 %. CP was long time before influenced by Pankl's quality system and forging technology as well as the engineering. Pankl itself is one of the long-term suppliers for all racing classes. From Rallye up to F1. A Pankl crank drivetrain is a different world in quality, performance and longlivety. It's a duty to blue print the quality around the drivetrain. Price level is high for their products. CP Carrillo is the lower price version of it for the mass market. A crank drivetrain (crank, rods, pistons) from Pankl is around 10,000+ Euro for a K20, from CP Carrillo it's about 60-70 % of it.

this should produce over 300 hp.
As above, in NA mode the 300 whp are hard to catch with an CR of 11.0:1. A 12.5:1 would be better as you need a fitting duration for peaking about at 8500 rpm. Those cams let the CR look low, around 9.8:1 if you translate it from alternation of load into a static CR.
 

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Discussion Starter · #34 · (Edited)
Hey Lotus, yes that's the head I went with although I haven't pulled the plug on cams yet.

😕 Honestly now that yo mention it I should have gone higher compression lol. There's so much info out there I wasn't sure what to go with, so I went 11 to play it safe. I was looking at other 11 compression pistons from CP but they were for a bigger bore.

Looks like I could have gone higher especially with 93. I guess I should have come here and asked questions but I feel like I ask to many sometimes! Maybe I should put these back up on ebay and get the higher compression or just run these? It sounds like with this compression I will be closer to my stated goals in the thread title though.


Thanks for the info on Cp Carillo and Pankl, interesting stuff!

Before I buy the wrong cams like an idiot, let me know which ones you think I should get? Looking at Drag Cartel still.
 

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Arouse the DAMPFHAMMER!
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Before I buy the wrong cams like an idiot, let me know which ones you think I should get? Looking at Drag Cartel still.
An engine setup list would help to help you. I need: bore, stroke, valve size, head flow if possible, header and exhaust setup as well as the complete induction path. Regarding the fixed CR I've tuned some 87x99 engines lately which had upgraded valve timings and lifts as well as stock. None of these setups comes near to 300 whp. I think there are options to get near to 270 whp with an 11.0:1 and a 93 octane fuel. Texas can be hot in summer, a CR of 11.0:1 and 93 octane fuel is not a bad thing. I've seen customers in CAL with not optimal intake routings, which fight with 50 °C and more intake air temperature. A higher CR would a huge disadvantage. Therefore the routing of the air is an key at your place too.
 

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Discussion Starter · #36 · (Edited)
One more thing if I do shop for different pistons, do I want to get the 87 or 87.5 mm for stock sleeves? I'm getting conflicting info on piston size on stock sleeves when I search. I also changed my VPN to reflect more where I live ;)

😞 Looking back on my mistake of buying these I think it really comes down to me underestimating the WHP difference piston compression has. These pistons are very nice, shiny and polished face on them. I guess if good gas goes away some day I have some good back up pistons? 11 is a good compression in Cali right? 30 Horse difference is a pretty crazy thing to pass up in my mind for 600$ and I can sell these easy maybe give a nice Cali person a discount.

I really appreciate all the time you take to respond to me lotus, your knowledge on these engines is awesome!
 

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Discussion Starter · #37 · (Edited)
Another observation from reading a ton of threads on stock 87mm sleeves and 87.5mm aftermarket pistons. I wonder if there is enough slop in Honda's QC that some sleeves will fit larger after market pistons while some will not. Wish my block would get here it's stuck somwhere mid US lol!

I took the del sol on i75 i was scary. Going 65 felt oddly unstable compared to modern cars. I'm wondering if the super cheap tires on it have a lot to do with it I did hit 85 mph though. Also the clutch is absolute sloppy slippy garbage makes me wondering if it will just quit shifting some day. With all that said it was a TON of fun haha! Noting like driving a clap trap.

Okay got an update from UPs and and its coming monday now it's pretty close now! This is my first time buying a block I'm excited!
 

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Arouse the DAMPFHAMMER!
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do I want to get the 87 or 87.5 mm for stock sleeves
I would see 87.5 mm the max. overbore of the K24 OEM liner. The stiffness against dynamic pressure caused by combustion get significantly reduced when you go over it. The purpose is not power, almost not worth. The real purpose is getting a precise new torque plate honing. The aim is to get a circular hone which is still circular under torqued (head mounted) conditions. The block get warpage'd when the head is mounted by the tensile forces of the head studs.

11 is a good compression in Cali right? 30 Horse difference is a pretty crazy thing to pass up in my mind for 600$ and I can sell these easy maybe give a nice Cali person a discount.
Like I've mentioned I've tuned some 87x99 engines in CAL and TEX which had a rare 11.0:1 compression. This engines run great. But it is just no basis for an 300 whp setup. See an example here: Official: Dyno Chart Comparison & Calibration Registry | Page 63 | Honda / Acura K20a K24a Engine Forum. To get this 87.5x99 block to 300 whp you need following:
  • redline setup around 8500 rpm, which is already hard stuff regarding forces in the crank drive
  • forged and balanced crank drive setup
  • well designed header and intake manifold as well as exhaust and intake
    • intake, when a single TB is used, mass balancing is a key factor, with the stock manifolds this is very challenging
    • intake, coldest air as possible. Intake routing is a key factor
    • header, need to support the 8500 rpm area
    • exhaust, muffler and exhaust piping are against the aim, the must support the aim
  • deep valve pockets for good midrange as cams need a bigger duration to support up to 8500 rpm. Big durations need huge valve pockets to advance the cam. Otherwise you run retarded on VTC and midrange power will significantly suffer. See an example here Official: Dyno Chart Comparison & Calibration Registry | Page 63 | Honda / Acura K20a K24a Engine Forum, lost 20 ftlb'[email protected] rpm just by retarding from 50° to 40° for safety reasons (piston to valve clearance).
  • ports, need flow well, a bigger valve setup can be a supporter if done right. Losses down low are the disadvantage of that, but in a race car application this doesn't matter
  • Cams, as you saw the DC 3.5 are still to small to support in that are. Of course other facts like the intake and IM as well as the header were also limiting, but a bigger duration helps to get both fixed, the scavenging phase as well as the ram phase for beyond 7500 rpm. The bigger the cam the bigger the CR must be, with all disadvantages at low speed cam (shorter duration + high CR = good requirements for knock ;)). Therefore the 11.0:1 CR is not a bad choice for a daily, but it would be huge challenge to get into the 270 whp and higher.
  • CR is depending on cam and application, for 300 whp on a 87.5x99 you should reach out for 12.5:1+ and cams like DC Elite 002.5 or S2 Ultra 2...in that range. These are huge cams and affects idle speed and VTEC switch engine speed significantly. A lowest MPG value should be no requirement in that project 😉.
There are more essentials to look at, but this list is already too long. A maybe S2 colored simple setup is posted here: Simple 300whp recipe. K24/20 with all shelf parts. Also Dc4 vs Ultra 2 graph - Honda-Tech - Honda Forum Discussion, they discuss there the effect on cams: DC4 vs S2 U2. Read with care, but it's an indication, the DC OG series has not the lobe design of the Elite series. Therefore I won't recommend for your goal the easy way.
 
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