At this point i have a pretty serious concern with the rebuild process, and it is the crankshaft.
It looks like it is perfect shape. Functions perfectly as far as I can tell, and I'm assuming it was rebuilt/replaced when the engine was "remanufactured" and sleeved by the first shop. I am very leery of touching anything on this engine that actually seems to be functioning as it is supposed to, and even if it is original i dont feel like 120k miles is the end of its' life cycle.

I am terrified that if i have the crank removed and machined that somewhere in that process something is going to be messed up and I will have to pull the engine again over the crank. Is it really necessary to machine it? And I have no idea on where I can find a shop that is familiar with the important nitrating procedure on these cranks. I want to do what is best for the engine but I definitely cannot afford to create any additional problems.

Opinions?

 

At the very least, mic the journals. If you can't do it, a competent engine machine shop will easily be able to. From there you will be able to determine whether the crank is good to use, doesn't make any sense to jump straight to machining it.

 

Like was stated, you have to at the very least inspect it yourself. Some pics of the crank would be nice, if the journals are flawless, mic them to see if they're in spec and carry on. I agree, it's best to take a light touch approach to re-building these engines, and to stick to OEM parts as much as possible. Seeing as you're sleeved, if you can machine the block you will need non-frm pistons, the good news is that non FRM pistons are cheaper. K series engines I believe have the same exact bore as the F20/22 so that could be an option as far as sourcing pistons.

 

I agree with everything stated on this, I will have the machine shop the engine is at now inspect them and see what they think is needed. They are a very reputable shop I have worked with for years and I trust their opinion. They are currently getting the measurements on the cylinders to see if they can hone it out and retain the stock bore or if that is not possible the other option is to go .020" over and grab some 87.5mm CP Pistons was my plan.

i never thought of sourcing K series Pistons to keep the engine stock. Would this really work and would I be better off with used OEM Pistons versus new aftermarket? Obviously contingent on keeping the stock bore.

 

If the pistons are within spec there's no reason to replace them. Used or otherwise. New is perfectly fine, I'm just saying Honda makes good pistons, when people downgrade to aftermarket pistons it's your gain. The 2.4 K-series has the same bore as the F series, and you have choices regarding compression ratios. Should you want to run boost or whatever, not to mention actual availability of OEM oversize pistons. Only downside is that FRM is lower friction material than steel sleeves, so the FRM is more tolerant to continuous high rpm use.

 

piston on cylinder #4 skirt is beat to s**t, I definitely have to replace, at the very minimum, that one, but everyone on here has been telling me the reason the engine failed was because of FRM-style Pistons with an iron/steel sleeve. I see the value in a K series Piston but it seems like it would be ignorant to put this engine back together with OEM FRM S2000 Pistons.

 

Oh for sure FRM pistons are no longer an option for you.

 

K series have valve recess differences on the pistons as well as little end at 22mm instead of 22.9mm
non oem pistons require non oem rods at 23mm

 

I believe I will be choosing a piston/rod combo from this site:
Pistons & Rod Combos

Leaning towards CP pistons and skunk2 rods.

 

Did you ever give Pure Tuning in Toledo a call? It may be worth seeing what they can do for you.