Whats the difference between H22a engins and H23a engins???

You have a h22a motor.

the h22a is the dohc vtec prelude motor used in all 93 and up vtec lude's.

the h23a is a non vtec prelude motor used in all the 92-96 si lude's.

basic difference's though:

-displacement
si lude-2259cc (138 cu. in.)
vtec lude-2157cc (132 cu. in.)

-bore x stroke
si lude-87.0 x 95.0 mm (3.43 x 3.74 in)
vtec lude-87.0 x 90.7 mm (3.43 x 3.57 in)

-compression
si lude-9.8:1
vtec lude-10.0:1

-valve gear
si lude-belt-driven dual overhead cams, 4 valves per cylinder
vtec lude-belt-driven dual overhead cams, 4 valves per cylinder, variable timing and lift

-horsepower (sae NET)
si lude-160 [email protected] rpm
vtec lude-190 [email protected] rpm

-torque (sae NET)
si lude-156 [email protected] rpm
vtec lude-158 [email protected] rpm

-redline (not fuel cut)
si lude-6500 rpm
vtec lude-7500 rpm

some other difference's but that the most of it.

Thanky