B18A1 vs. B18B1 vs. B18C1

Everyone I ask has a different answer about this, so I turn to you for as an authoratative source. Which parts are the same/interchangable among these 3 engines and which are not? (b18a1, b18b1, b18c1, other b18?) I thank you in advance for your consideration.

Pistons and transmissions are interchangeable between all.

Almost every part of the B18B and B18A are interchangeable between each other. But between the B18B/A and B18C's (B18C1 and B18C5); the rods, cranks, heads, even the physical block heights are different.
There is a way to put the B18C1 and B18C5 heads onto B18B/A blocks, but it's not a direct bolt on thing. There are kits available (and instructions online) so you can do it.

The heads are slightly different between the B18C1 and the B18C5, the intake manifold bolt pattern is completely different (though the B18C5, B16A, and B16B all have the same heads with different cams and valvetrain). Though, the B18C's share the same rod length, cams are interchangeable, valvetrain is as well, and you can swap the heads (B18C5 head bolts directly to the B18C1 block and vice versa).

Those are some of the major parts that are or aren't interchangeable. If there are any other specific parts you're wondering about, please feel free to list them and I'm sure someone will be able to help you out.

can you tell me more about a1 vs. b1? What makes them different?

OK, what i really need to know is how to make my B18A1 INTO a B18B1. I want to put my B18A1 in my '94 del sol and be emissions compliant. That is what i'm getting at. Thanks again!

Really depends on what they check for. You're definently going to need an OBD1 ecu (for a '92-'93 B18a or '94-'95 B18b). You'll also need an OBD1 LS distributor, as well as a 4-wire O2 sensor (already equip in your vehicle). You're also going to need to get a hydro B-series transmission or you're going to have to buy a kit to use a cable transmission.

How bad are NYC emissions testing? I'm in Syracuse and we only test OBD2 cars here ('96 and newer). If they do a bunch of visual testing, you might have to get a '94 or newer B18B1 and ecu.

Here you have dyno emissions on OBD1 and older. (NYC, long island, Rockland, And Westchester) But I don't think anybody would actually look at the block and check to see if it's an A1 or a B1. As long as the DMV computer recognizes it as OBD1 and it passes the dyno test I'm sure it'll be ok. I've been told that the intake manifolds and throttle bodies are different, and I know for sure I'll need the B-series hydro trans and the OBD1 ECM. I didn't know about the distributor and O2 sensor. The other problem is the car is a D15. I know I need axles and shift linkages to switch to the B series. I wonder if perhaps I can use the d series engine harness and ECU? Well, I guess as long as the A1 and B1 long blocks are the same, I'll buy a B series hydro trans, get the A1 long block & the hydro trans in the car, change the linkages and axles, put a B2 distributor on it and see how things line up. Any other info you can give me on what sensors & stuff are different would be a big help. If anybody has pictures of a B1 in this car that would also help. Anybody in the NYC metro selling the stuff I need? I'll let you know how it's going and keep in touch. If all goes well I'll take pictures and write a very specific how-to. Thanks again!!

You should definently use your existing harness, o2 sensor, injectors. And if you want it to run at full potential you'll have to use a different ecu. You stock ecu will let the engine run, and you'll be able to drive it but it will be a dog. And I'm not sure how it will effect your emissions. Here's a link that might be helpful (you don't have to worry about vtec or the vtec ecu): http://honda-tech.com/zerothread?id=983454

Thank you that link is perfect!! Now I have as much info as I think I need, I just need the time, money, and ambition. Thank you very much I'll let you know how it goes.

Just to let you know that the actual tall block of the B18A and B18B is identical, so people however say that the B18B head flows a bit better though. If you want a full swap for your del sol, get it out of the B18B equipped car so that you already have the hydro tranny, B18A cars came with Cable trannys. Wiring is also a bit different.