[nikos]

In Japan, a Tuning Magazine called Hyper Rev, just published a story.

Apparently, using HONDA OEM PARTS , they were able to make a 2.0 L K20a into a 2.3 L. TOP FUEL JAPAN, did it and they are soon going to be offering this as KIT.

These motors are 86 mm x 96 mm using b16b rods. In case you don;t know, B16B pistons infact ARE longer than B18C/C1/C5 rods. They're actually the longest B series rods. The exact legnth is unknown.

They dynoed this setup in a Civic Type R and saw a 50 HP gain with whatever else they had in there. Keep in mind, that they revved it to 9000 RPM with no problems.

Tomorrow check back and I will post scanned pics of the article in Japanese.

Some food for thought...

After looking here, http://www.raceseek.com/honda_specs.htm

the only crank that is close to 96 mm is the h23a1 and h23a4 which is 95mm out of the 92-96 prelude and 97-98 prellude.

Any ideas about converting the crank to a chain? Journals?

The length of b16b rods seems to be impossible to find. I cannot get much info on the cranks as well.

 

[civdx94]

f22/h23 rods journals are the same width as ls/b16, and you can reduce the journals 3mm to accept the ls style rods. but doin the math i don t think it would give you a 96mm stroke using that crank. Since having access to CTR rods is not likely you would probably be better off tryin to use some eagle long rods at 280 a set, you could play with a variety of r/s ratios.

 

[non vtec]

Most of the CBR honda motorbikes run 96mm stroke's, so maybe they modified one for the K-series, plus they are chain driven aswell I beleive, be interesting to look into it. Maybe it a big bike crank.. Either way I think it would still work out cheaper to get a Stroker kit from Crower...

 

[civdx94]

haha maybe not with the goin rate of bike parts on good ole ebay, you might be able to pick up a cbr crank for next to nothing, need the bore spacing, journal information, etc. of course with the CTR rods ranging somewhere from 138-144, none of which are that nice geometry wise 1.5 r/s at best

 

[nikos]

Good idea. Gary.. lol CBR cranks.. lol you never know

 

[fearless_dsm]

Cliff notes,Nikos?

 

[nikos]

Sorry... No honda bike has that stroke.. I don't feel like looking at 4 wheelers now

 

[nikos]

It has to be the h23a1 crank

 

[nikos]

here's the h23a1 crank

and here's a kseries one.. maybe the gear/belt parts interchange?

 

[civdx94]

snout diameter?

 

[import_trung]

i can see the resemblance (sp)
but would the bearing shells be a different o.d size. plus the f23a has secondary balancer shafts, that could affect things....

 

[brian g]

the only crank that is close to 96 mm is the h23a1 and h23a4 which is 95mm out of the 92-96 prelude and 97-98 prellude.

Any ideas about converting the crank to a chain? Journals?

Nothing new here, you just offsett grind the 95mm crank. Converting the crank to chain is easy too, by machining the nose of the crank to resemble that of the K-crank. They've been doing this in the US for a while now.

BTW, I seriously doubt any motorcycle crank has the same bore centers as a K-series motor.

I think the CTR rod is 142.8mm

brian g

 

[- guest -]

Nothing new here, you just offsett grind the 95mm crank.

brian g

I just posted some pics that illustrate this exact process in the crankshaft thread:

http://www.k20a.org/forum/showthread.php?goto=newpost&t=2378

This is actually a few steps beyond and preferable (IMO) than just offset grinding to a smaller journal.

-Ron

 

[K2e2vin]

The length of b16b rods seems to be impossible to find. I cannot get much info on the cranks as well.

from using what we know you can find the approximate length; height from crank centerline to top of deck: 181.5mm(they say its the same block as the B18C's), 77.4mm stroke

181.5-(77.4/2)=142.8mm
edit:Brian G already posted it

 

[z10]

pics are up

due the the large size for easier viewing and clearer pics , i will not link the pics directly to this tread

just click on the link below to view

http://www.k20a.org/z10/k231.jpg
http://www.k20a.org/z10/k232.jpg
http://www.k20a.org/z10/k233.jpg
http://www.k20a.org/z10/k234.jpg
http://www.k20a.org/z10/k235.jpg

 

[GT MOTORING]

this is actually pretty old news, ive had the issue of the hyper rev EP3 for some time now, of course i cant read japanese, so that doesnt help me get the details. ill ask one of my contacts in japan to see if he has time to translate it for me, if there is enought people wanting to know. maybe in the text of the article the crank questions are answered.

Greg

 

[11248c]

Hey Nikos we know Top Fuel of Japan is a reputable company, but how much should we expect this "kit" to cost???? Would it not be cheaper with the same effect, just to bore the k20A2 block?????

 

[nikos]

boring will not do it... You need the extra stroke

On another note, f22b f22a and h23 all share the same crank

Same part number Honda #13310-P0A-000

 

[z10]

i can read some japanese

and iw ill list out some points in the article

-they tried using k24 block but failed (breakage and wont rev)

-modified k20a piston

-modified b16b rods

-modified crank (apparently the crank if belt driven orginally)

-the bore is 86 and 96mm stroke (they claimed no problem in reving to 9000rpm all day long, they use it for circuit racing car)

-CR is 12.1

-heaps better compare to 99m k24 stroke

-they will not disclose the spec of the crank (trade secret)

 

[nikos]

I just bought a set of CTR rods for $60 just for kicks.