but sifu shiro.... suggested clearance, 0.0025" = 0.0635mm ... is like nothing already, my mech say no nid bore la, sumbat saja.. what u think?
Depends on where you measure, you can see where they recommend measuring for the clearance on the spec sheet. Can try run looser a bit, like 0.0030-0.0035. 0.0025 is kind of tight. If NA, I'd probably run the 0.0025 recommendation, but not for turbo. You should always check with wiseco as well. Remember to tell them that our ambient temps are usually in the mid 30s to 40s degrees celcius when on the road, and how much boost you expect to run. I think they'd recommend running looser as well, but email them to confirm anyway.
Anyway, if sumbat only, where are you going to get your ring seal? If you do like that, sure the engine will run, but your engine will also consume oil really quick. (think "4 litres" of engine oil top up in two weeks if you drive a lot) Need to rebore and rehone at the minimum if you want engine to last, need to check if they all can fit the minimum 0.0025-30 (or whatever clearance you choose) The pistons are EXACTLY round or have the exact width at skirts, so if you don't check properly, one of them will be 'tighter' than the other, and that's the one piston that's going to give problems later on when you apply boost, which makes a lot of heat, and that clearance will reduce to zero or less than zero, then clunk!
If you escape with scored sleeves, consider yourself lucky. If clearances check out and you don't need to rebore, must still at least get a bore hone, that's for your oil control ring seal. (they aren't built like the top two compression rings)
Make sure you get a good machine shop to do the work though, had a head and block spoiled by a incompetent one before. With honda engines, everything must be in spec or you'll always think the engine is unreliable because it keeps spoiling. You wrongly torque the main caps also the crank will start to eat the bearings. Each piston not exactly round also, so the machine shop should be able to check for roundness, and bore accordingly to the specs. Just remember that the clearances they put on the sheet is the 'minimum', in real life, it will always be a bit looser, but we want the minimum so the piston don't seize when it sees a lot of heat, that's all.Don't go too loose however, or when starting in the morning, the engine will be plenty noisy.
If you want to see the process of building engine, this is a good source. Part 1-3
Evans Tuning GSR Engine Build Tech Article - Part 1 - YouTube
Evans Tuning GSR Engine Build Tech Article - Part 2 - YouTube
Evans Tuning GSR Engine Build Tech Article - Part 3 - YouTube
A lof of people fail to check the oil pump clearance (part 3), so sometimes they kill the oil pump without knowing. (actually not kill, it's just that the oil pump gear part where it meets the crank will start to wear, then when it does enough wear there, it starts to wear the housing. This takes a long time though, but it's the difference between changing oil pump at 200,000kms, or 500,000kms.)
I have a b-series oil pump that has like 350,000kms on it, and it still looks new, and clearances checks out. Damn honda makes this thing crazy lasting.
Also got lots of other videos from him that's very useful, if your mechanic has not much experience with honda engines/transmission/etc.
Nice parts BTW. Good luck with the hondata. Check resistance of injectors before installing. If less than 10ohms, install a resistor box. Let me know the resistance too, I want to compare to some other honda injectors.