b18a1 to b20?

[jhpate]

Hello new to the forum. Yes I have been searching and yes I know its possible but not being a honda guy I need some information on what would need to be changed. My friends son bought a 88 or 89 crx that had a b18a1 swap installed I believe running obd1. Had it a month and threw a rod through the block. Will a b20b bolt up to the cable trans without a hitch? What else would need to be changed? Will the mounts be the same? Same dizzy? Same exhaust? I appreciate your help and thank you.
James

 

[phunky.buddha]

You can basically just change out the short block and leave everything else the same- use all the same electronics, head, transmission etc.

 

[jhpate]

If we use the whole long block what would need to be changed? Thank you for the respone.

 

[CAFROG]

Dizzy and Alternator b/c B20 is OBD2

 

[CAFROG]

And you need to use the Old Intake Manifold/Throttle Body. But everything will bolt up with no problem

 

[jhpate]

so if b20 is obd2 would that require different ecu? More sensors?

 

[isthisnameok4u]

The ecu should go with whatever head you are using. The LS and B20 heads are identical, as far as cam and cc's but all the sensors are different. You could just do a block swap if the old head wasn't damaged, or else taking everything off the outside of the old head( intake, fule rail, injectors, dizzy, alternator) and bolt these to the B20 head to avoid more wire headachs.

 

[CAFROG]

Just take the intake manifold off the old motor (Complete with Throttle Body/injectors/sensors) Then the alternator, and the distributor. Replace these parts onto the B20. You also need the old engine wiring harness but its no big deal if you label them. maybe look at the clutch too. No need to mess with the ECU if you change over those things. It'll pretty much be the same set up but with a newer, bigger bottom end. That CRX will jump off the line pretty hard with the 2.0 block. A VTEC transmission and it'll scream into low 14's maybe 13's with a good driver.

I would take the whole motor/trans out with a cherry picker, change things over, then re-install. After the axles are out....Its easy and lowers the percentage of getting a sore back/nuckle busters.

 

[CAFROG]

I suggest timing belt and water pump while its out. OEM For The Win

 

[jhpate]

thanks guys. I have already screwed the pooch once. I bought a new b20. turns out it is a b20a5. wont work.

 

[jhpate]

sorry one more question. You said I need the old engine harness. I assume you are talking about the one in the crx now with the b18 in it. Correct?
thanks,
james

 

[CAFROG]

The Harness that was attached to the B18A1 when it was all working in the CRX.

Whateva B20 you get...the Intake Manifold wont fit (plus you need the OBD1 on there anyways)

 

[jhpate]

Ok, thanks again guys. Just wanted to make sure.

 

[Fernpatch]

would you be interested in selling the b20a5? I know a guy who is looking for one.

 

[jhpate]

yes we are trying to sell it.

 

[jhpate]

send me a pm so I can send you my contact info.
thanks

 

[Fernpatch]

pm sent.

 

[jhpate]

I sent you a email fernpath.
thanks, james