I have 1990 Integra GS w B18A1 that needs rebuild (recent post) but have also heard that a B20B will fit perfectly in B18A1 'bed' w no adjustments...is that true?

If so, seems like a good idea to upgrade...if I can find one.

G

 

Your car is OBD0, depending on the year of the B20 you will need an adapter harness for the ecu. Other than that you are fine.

 

Thanks ... but what is OBD0?
G

 

OBD: On Board Diagnostics. tells you whats going on with your. Ecus are different from obd 0,1, and 2.

88-91= OBD0

92-95=OBD1

96-00=OBD2

You will need a obd1 ecu, and a harness that will connect the ecu to your cars factory ecu harness. Like this one: http://www.boomslang.us/obd0to1.htm

Also, You will need to get it tuned for the B20B.

 

and reuse your b18 intake manifold

 

o/p yes you can drop the b20 in with no mods, even using your stock ecu/dizzy/etc. only thing that's bigger on the b20 is the internals, exterior is the same as your ls.

will you get the full potential of the b20 by using your stock 1.8l parts? i don't know. but you will be able to drive the vehicle just fine to where you need to go.

 

all b20b engines were obd2. however, there's no need to convert anything.
OP, the motor will drop straight in. just transfer over your distributor, intake manifold, and exhaust manifold. the only thing you'll need to modify is the fan switch wiring. on your 90 integra, it plugs into the back of the block. the b20b has it on the thermostat housing. extend the 2 wires and use the b20b fan switch connector. that's it. you may want to purchase an adjustable fuel pressure regulator and ramp pressure up to 50psi. or, you can have your pr4 ecu tuned for the 2.0L