Need info about my engine

Okay so I bought this integ(1994 LS, 108k miles) around the end of august. When I looked over the engine I was really surprised at how clean this guy had kept it so I asked him about it and he said that he washed it every time he cleaned his car. So I left it at that. Well I took my car in to get the oil changed a few weeks ago and the guy tells me that the engine in my car isn't the original. I was a little suprised, but sure enough it is a B18B1 where it should have been an A18? I think... This is where my question comes in. I know that the engine is newer than the car, but I don't think that the guy that sold it to me knew that. I have no documentation on the engine swap (why it was done, when, at how many miles). I also don't know how much of the engine was swapped. Could have been the whole thing or they could have left the orignial block. Just wondering if anyone knows anything about this kinda swap, any problems I should look out for if it is the old block with new heads, any info at al would be nice. And I don't suppose there is ANY way of knowing how many miles are on the new parts?! Any info would be awsome, thanks.

no such thing as an A18. Theres a b18a, but thats in older LSs, and you'd have a b18b regardless. As long as it says b18b on the block, and the head should have a date on the back I think. As long as its newer than 94, and you dont notice any problems just driving it should be fine. If there havent been any problems yet(assuming it WAS changed) then you're fine.
Oh yeah, and one more thing, dont get your oil changed there anymore, in fact, keep your car far, far away from that place.

Hmm, well I wasn't sure what the ID was. I just made up the a18 part, couldn't remeber what he told me. And the guy who changed my oil wasn't just pulling things outta his ass, their database said that the engine should have been one of the following(A or C?) and the engine I had in there wasn't, that's all he told me about it. He said that the computer said it should either be an A or C if it was the original engine. In any case I'll check on the year and I haven't had any problems with the engine only with the tranny for some reason every once in a while when I shift fast from 1st to 2nd it grinds. Any ideas?
Thanks
Keen

yes the mechanic was pulling things out of his ass. The 94 ls is a b18b1, as are all ls's. The gsr's are b18c1's and the type-r's are b18c5. I dont know of any integras that are b18a's ( correct me if im wrong). But i am very sure your ls came stock with a b18b1 engine.

Yes you should have a B18B1 the guy at the shop must have looked up the specs on a GSR instead of a LS or the computer they have is wrong. The only integras that came with the B18A1 is the 90-93 LS,RS,SE.

a18 IS A VIGOR rwd,LOL

yeah there are no a18 or bi8a's.... there is a b16a but that is in the civic si and sir........the mechanic is full of shit and you should go back and slap him........if you are really worried about this then run carfax on it and it should tell you the code........or i think the vin numbers should also be on the engine.......match it with the one on ur dash and see if they are the same...if not then its not the orig engine

I don't know about your particular engine, but my '98 GSR has either B18C1 or just C1 (I can't remember) stamped on a flat part of the casting of the engine block. It is on the passenger side of the car below the VIN plate on the motor near the transaxle.