i dont know if there is any difference in the blocks themselves, but i went ahead and sleeved a k20a3 block.

 

rod journal on crank is smaller than a2 and k24. block seems to be same.

 

so the only difference is the crank cheetah?

i know the blocks are pretty much identical... the a3 even has the boss for squirters casted but just not drilled.

 

yes, the a3 can use the squirters and the oil cooler... the access to the oil cooler is behind that bronze cap behind the motor... open it up, and remove the brass plug, and slap the cap back on. I forget where the switch is for the oil squirters or if there even is one on there...

 

So it sounds kinda like a b18b to a b18c. All most the same but not.

 

Are the internals the same...Pistons/rods? and it's the crank that gives the different compression? or no?

I'm kinda thinking the A/a2/a3 all have different rod/piston combo's. Do the a2/A have the same crank?

 

not the same crank. smaller journals. I had to get a type-s crank for my setup. plus the a3 has 9.8 to 1 compressions and the rods are weaker.

 

so we can gut an A2 block and put all the internals in an A3 blocks with no problems, everything will bolt in with the addition of drilling out the oil squirters?

 

Correct. You also have to tap 2 holes on the back of the block for the coolant lines for the oil cooler.

 

It would be cool if someone could do a detailed how-to on converting the A3 block to have oil squirters. Also, who knows of a good place to get the PARTS for this. I'm basically looking for the acura equivalent of hondapartsdeals.com .

 

Not much involved in the conversion. Jut need a competent machine shop to drill and tap a few holes. As for parts ... www.acuraparts247.com .

 

Not to mention that if you go with forged pistons, you can leave the oil squirters off (as long as they're not fed oil, if they are, just pinch them off) and increase the oil pressure in the rest of the engine since forged pistons don't need the squirters. Sounds like if you have an k20a2, and need a new block for F/I if you damaged your old one or want to do a new build, doing a k20a3 block with the oil cooler holes added with your original a2 crank is the way to go. Cheap, and lots around.

 

Yup, or just run an aftermarket oil cooler and just swap in an a2 crank.

 

so since when are the rod journals different sizes? granted i looked for the info from rod manufacturers who say a2/a3s use the same application. i believe i ve even asked edo and nikos about this information, and it was just word of mouth standpoint unless somebody has a helms laying around to verify.

 

they are the same rod jornal diameter <-----honda technician has the manual

 

they are the same rod jornal diameter <-----honda technician has the manual

But the cranks are different though right, regardless of rod journal size?

 

so, after reading all this - the cranks are the same between the a2 and a3.

stroke - same
rod journal - same
mains - same

 

they are the same rod jornal diameter <-----honda technician has the manual

I don't think cheetah was speaking about diameter...

 

I had my block sleeved by benson and (earl) he told me I needed a a2 crank since the a3 crank journals were different.

 

heres something i found on hondanews.com

Engine Block/Crankshaft

The RSX engine features a compact aluminum block with cast-in iron liners- a design known for its light weight, high rigidity, and excellent durability. The block has a one-piece aluminum crankshaft carrier, which has ferrous-carbon inserts in the bearing caps for additional strength. The Type-S version also incorporates a stiff, cast-aluminum oil pan. The crankshaft is a highly rigid, forged-steel design that uses a special micro-polished surface finish for reduced friction and increased durability.

In addition, the Type-S engine uses high-strength connecting rods and crankshaft as well as high-compression cast-aluminum pistons for increased resistance to wear

The transversely mounted engine block with front- mounted intake manifold, positions the exhaust manifold closer to the catalyst for improved light-off and reduced emissions at start-up.

Dual-Stage Intake Manifold (RSX Model)

Now it doesnt say that the jounals are different sizes but it does say it uses a higher strength crankshaft. Now all we need is specs!!!

 

So from the sound of things the a2 and the a3 are the same except the cranks.....

So does any one know about the k24a4 vs. k20a2?? Are the cranks in the k24a4 engine larger than the k20a2 or are they the same. I heard somewere that the rod journals on the k24a4 are wider than the k20a2 but cant seem to find any materials to back this up any clues anyone? Thanks for your time in advance.

 

so, today, i put an a2 crank beside an a3 crank and checked the differences.

stroke - same
journals - same - that's why the a2 rods and a3 rods can be interchanged.

difference: counterweights. the a2 crank has more than a3. i'm guessing because the a3 uses balance shafts.

this is from a glance... if anyone finds anymore info or can correct me, please do so.

 

top: k20a2 crank

bottom: k20a3 crank

 

they're not the same, the size of the journal of the a3 is smaller 1.777 measure it. I bought a2 eagle rods and couldn;t use them on my a3 crank. the a3 rod journal is the same size as the gsr.

 

that's interesting as crower advertises and swears that they're the same rods for both applications. i'll measure them and post my findings.