i am think about a swap for my 91 Rex Si. i am wondering if i should go with a b16 or b18 and what model. just wanting some opinions this is my first rex. one other thing i am not so up on body work and want to know how i can get rid of the groove and holes my side trim pieces on the door and fenders

 

both motors are good, the b18 costs more but has more power. The b16 will go in faster with less hassel, if your trying to do it yourself.

As for the body work. You need to tig weld the holes together, and then you can fiberglass / bondo them smooth.

 

which models would fit b18c1 b18a1 b16a1 i know difference between engines but just need to know if there is any difference in the dimensions and how well they will fit in my engine compartment

 

the mounts are the same, the difference is in the internals for the most part (unless someone can tell me different). Your also looking at different ecu's etc.

 

Any B-Series motor will fit.
HASport has mounts comming out soon to fit the H-Series in your crx
and another comapany is working on mounts for a K-Series motor in your CRX.

You have plenty of options pick what you like, or can afford.

 

B16 is the more cost effective in my opinion... K-series needs to re wire the whole damn car. and b18's cost to much... unless its a B18b.... your choice.. all have their difference's but all are fast as hell

 

thanks for the info.