So to start off, I have an extremely limited budget. About 400 bucks a month of spending money to work with for parts and machine shop labor. I Bought a b20z2 block a few weeks ago, it came with an LS oil pump, I also have a b20 and ls water pump, a Ls MPFI intake manifold, a LS exhaust manifold with test pipe, B20 pistons and rods, and a b20 crank. The crank is good, and block is good, pistons are okay along with rods. I'm thinking of Budget B20vtec, what would i need for a decent reliable build? I was thinking ARP Rodstuds and headstuds, forged pistons and rods, a b16 head with medium compression (in the 10-10.5:1 area) and keep the rpm at 8 or below, so I don't blow it to high heaven. Any opinions on how I could keep this on the cheap? I'm aiming for somewhere around 160-170 horse realistically. I'm not looking to make 230 horse or no crap like that, I originally wanted a b16 for the 160ish horse, but i like the torque of the b20, and it was a good deal! Help me out guys, i'm just a young guy on his first build looking to do it right.

 

What year is the oil pump? Buy/acquire a gsr/itr water pump; the ls/b20 pumps are not ideal for the hybrid vtec motors, cavitation at high rpm use. Ls intake manifold won't fit a b16 head. A stock Ls exhaust manifold is not exactly ideal for a semi built b20vtec. Since budget is limited just pick up a hytech replica from a company like PLM. Stock b20 pistons? Ditch them for a set of itr replicas from a company like rs machine. Stock rods are fine just get a machine shop to press in new arp rod bolts and resize the rods. Arp head studs are always a plus over oem head bolts. I don't like the oem bi metal ls/b20 rod bearings, they can't handle as much abuse as the tri metal bearings used in the gsr/itr motors. At this point I'll just tell you what to use, it'll be easier than rambling about specifics.

Block:
-stock b20 crank, have the machine shop check it for cracks and micro polish the journals.
-stock b20 rods, have the machine shop press in arp rod bolts then resize the big ends. Shot peening really is not necessary.
-itr replica pistons by rs machines or the like in 84mm bore. Have the machine shop install them on the b20 rods. Tangs on the rods go to the exhaust side, make sure they don't put the pistons on opposite of that. Arrows on the piston tops should point to the timing belt with the tang on the rod on the exhaust side of the engine.
-Deck the block if necessary.
-Hone the cylinders. To what grit will depend on the rings you use.
-Oem honda seals, thrust washers, and main bearings. Set the bearings at 1.6 to 1.7 thou on 1 2 4 and 5. 2 thou on #3.
-Acl race rod bearings. They'll take a lot more abuse than the oem bi metal rod bearings. Set them at 1.7 thou across the board.
-If you hone out the 84mm factory bore and use new 84mm pistons you'll probably be sitting at a 30 thou p2w clearance which isn't ideal for a cast piston but it'll be fine, don't panic when measure it.
-Check cylinder bore taper after honing. Really don't want to see more than a thou on the load axis.
-Piston ring end gaps, go by the factory service manual. You'll probably be on the outer end of the oem specs if you use npr rings that come with most aftermarket pistons. I think rs machine uses arias rings, if you go with them, you will have room to file them.
-Use a GOOD, not ******* harbor freight torque wrench when assembling. If you buy a decent set of micrometers that will measure accurately to the ten thou and a dial bore gauge that will measure down below 1.7 inches accurately to the ten thou you will be able to spec out all your clearances in the block.
-also, golden eagle ls vtec kit.
-get the entire rotating assembly balanced

Head
B16 casting
-shave it if necessary
-valve job to refresh the oem valves would be nice.
-run itr springs, seats, locks, retainers, and cams.
-new oem valve seals.
-replace the valve guides if they are worn.
-golden eagle cam gears
-upgrade to the newer beehive lma's.
-itr/gsr timing belt
-degree in the cams, then clay the motor to check p2v and p2h clearances.
-measure your v2v clearance across a range of cam gear settings.
-edlebrock performer x intake manifold if you can swing it.
-66-68mm throttle body. professional products tb's are cost effective and reliable.
-hytech rep header as mentioned earlier.
-rdx injectors are nice if you can afford to run them. alternatively throw a set of rc440's in. they'll give you plenty of room on the dyno.
-break the motor in on the dyno and then tune it on something that isn't crome(cui's rom editor).

I'm sure I'm leaving stuff out but I tried to tell you as much as possible.