so i talked with my local performance shop guy and ask him what if i put a h22 head on my h23 block... he told me i would get some hp out of the whole deal...but sooner or later the bottom wouldnt be able to keep up with the vtec head...so i would eventually throw a rod or piston...is this true?...what if i were to put a h23 head on a h22 block...is it possible?...would i gain some good hp and trq? this might be a good solution for my whole ordeal with the bearings...

 

h23 head on h22 block is possible i'm sure, however i'm not sure about the compression ratio or valve to piston clearance. H22 has taller (domed) pistons, H23 has a slight dish. also the h23 head has a much smaller combustion chamber.

as far as h22 head on h23 block, i am running one right now and am quite impressed. 30K miles thus far absolutely no problems. If you plan on revving to 7500 on a daily basis, the h23 short block will not take the abuse like an h22. Due to the longer stroke and worse rod/stroke ratio, a stock bottom end h23 won't make that much power at 7500. The good thing about H23 is the torque and hp curve happen at much lower rpm than H22, so the extra rpm's are wasted.

 

the h23 bottom end will take it if the bearing clearances are spec'd appropriately and the bottom end is balanced. BALANCING IS KEY.
But then its not exactly a stock bottom end......

either one is possible as the blocks are identical.

 

if i have an h22a4 block, will my h23 crank i have fit in it? i heard that the main journals were larger, so i'm trying to find out if i need another block for building this engine...i was planning to run TYPE S pistons with CROWER H23 Rods also, so will the h23 block handle the TYPE S pistons like the h22 block? thanks guys

 

depends what year a4 block you have.

92-97 and some 98's have 50mm mains
98+ have 55mm mains

if you would read this thread, it was noted that inside the years above, all H series (excluding SH) are identical besides oil pumps, water pumps..etc.