Honda / Acura K20a K24a Engine Forum banner
1 - 14 of 14 Posts

·
Registered
Joined
·
57 Posts
Discussion Starter · #1 ·
Does anybody have anymore info/specs on using a k20 block and throwing in a f20/f22 crank??? Procedures,which one to use,results...????? Im interested in building a setup like this. Thanks :dance:
 

·
Registered
Joined
·
1,117 Posts
f20c= 84mm stroke
f22c= 90.7mm stroke

snout modification is necessary for k series timing gear. New rods because of wider rod bearing and different length depending on what crank is used. either longer rods for the 84mm stroke and shorter rods for the 90.7mm stroke crank.
anything can be done with enough $$$$, just depends on how much you want to spend.
 

·
Registered
Joined
·
57 Posts
Discussion Starter · #4 ·
Thanks...It turns out to be more like a undersquare motor with the same bore of 86mm but a longer stroke using the ap2's cranks and the other way around with the ap1's crank. It must rev pretty high then with the f20 crank right? This setup is more pointed to an all motor setup. Has anybody done this setup and have results/numbers??? This is another reason why i love Hondas :heart:
 

·
Registered
Joined
·
1,117 Posts
hytech has crank offerings for both the k20 and k24 blocks. I would start off with the taller deck of the k24 block. that way you can have a longer rod.
also inline pro has a lot of experiance with both k series and f series.
 

·
Registered
Joined
·
57 Posts
Discussion Starter · #6 ·
ok thanks for the info...i know for sure im building a k series project motor...i think im going to just go with a k24/k20 hybrid or just a k20a2/a....then boost them later. Im just trying to see all the possibilities with the k serires motors. i love it
 

·
Registered
Joined
·
57 Posts
Discussion Starter · #8 ·
oooo i never heard of ppl doing that but sounds cool well the f20 has a 84 mm stroke and the f22 has a 90.7mm stroke and the b16 rods are like 77mm so do the math...
 

·
Registered
Joined
·
57 Posts
Discussion Starter · #10 ·
narrow?wouldnt u want it to be bigger to fit on the crank journals so it wouldnt have any play???i dont kno the specs on the rods of the f20/22 but i dont see that...
 

·
Registered
Joined
·
1,117 Posts
b16 big end dimensions are different than that of the f series. the stock rod is physically narrower. And Im prety sure the diameter for the bearing is different. but im not 100% positive. I know that in my v8 design based off the f20c I am using the b series big end dimensions on custom rods based on the f series engines. so that I could fit 2 rods on one journal. The b series rods are wider than that of the k but narrower than the f. Only way to fit a f series crank in a k is snout modification and aftermarket rods. the prelude h22 and h23 cranks also fit with modification.
 

·
Registered
Joined
·
1,117 Posts
wow, interesting to know. I don't have any more b series rods to measure but Im sure anything is possible. the journals would have to be welded to match the width of the b series rod which is narrower than that of a f but wider than a k. Can't remember the big end diameter. it may be the same. Or the rod journal could be ground down to fit the b series rods. Running a smaller diameter bearing should reduce bearing speeds from what Ive read. and going with a wider rod than stoxk k series would help with rod bearing failure. going back to what works but not too wide to sacrifice hp by added friction with the wide rod of the f series. Thats a whole nother topic that could be discussed in the advanced engine theory and design.
 

·
Registered
Joined
·
57 Posts
Discussion Starter · #14 ·
wow interesting....i would love to got to a machinist school or just become an apprentice somewhere...i can build motors but the machining is the only thing i cant do by myself....but for the k series project im thinking im just going to build a hybrid for now then boost it when i save enough money...cant wait...thanks guys for your info and advice
 
1 - 14 of 14 Posts
Top