So ive been told that my engine isnt a good one to start to rebuild cause there isnt very much aftermarket support. but can i swap out heads with another engine? and if so what engine or engines can i swap heads with, and if so will the bottom end of my engine take the power after i build the head up with cams? or should i just say screw my B21a1 and get a whole other engine to start with........for the love of the car gods HELP ME!!!!

 

the B21A1 is from the 90-91 Prelude Si's.... it was Honda's first attempt at an engine utilizing the FRM cylinder walls that many later engines have used more successfully.

Bottom line is this, regardless of your performance goals that specific motor isn't worth putting money into. With a 3rd gen Prelude you pretty much have 2 options for going faster reliably:
1. Build a B20A5 for boost and turbo it (cheaper option)
2. Swap an H22 in. (more expensive but more aftermarket options down the road)

I'd highly suggest reading up on all the info we've collected at PreludePower.com because you'll probably find out more than you had ever wanted to know about 3rd gens there

 

You can swap it with lots of engines.A b20 or b18a/b would be the easiest.The b21 is not worth working on.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by NJIN BUILDR &raquo;</TD></TR><TR><TD CLASS="quote">You can swap it with lots of engines.A b20 or b18a/b would be the easiest.The b21 is not worth working on.</TD></TR></TABLE>
Actually only the B20A/B21A engines are "easy" (they are interchangeable).

Swapping in a B18 would require even more work than an H-series because you'd have to cut a hole in the floor for the 'normal' b-series shifter to be in the car.

All Preludes from 88+ are cable shifted, thus you don't have to change the shifter when swapping an H22 into a 3rd gen.

 

can anyone tell me where i can get a b21a1 or direct me to a forum that can help