Hey, I'm thinking of building the G23 Frankenstein engine for my 5th gen base but I'm reading different opinions about this build so I'm starting to wonder if it's actually worth the time and money. I already have an F23A1 block with stock internals and a H22A4 head and would like to hear some opinions from people that have experienced this engine.

 

not worth the trouble

 

It doesn't make any more HP/Torque than a JDM H23A VTEC... so do you choose to go through the trouble to make it work and save a few bucks, or just buy the H23A ?

 

No.

 

These answers are disappointing. I would assume all have had experience with the g23....

 

What, you mean you bought into the Internet Hype of the G23 ??? Now if you use logic to evaluate the G23 combination, you will quickly see that the hype is simply that. The bore and stroke of the G23 is very similar to that of the H23A... 86mm/97mm and 87mm/95mm respectively. This would suggest that peak power and torque will be similar between the two engines if all else is equal. However, the F23 pistons have lower compression than those found in the H23, and the H23 cylinder head combustion chamber has a greater volume, so a stock F23 short block with a H22 cylinder head will create a really low compression engine... slightly less than 9:1 in fact. Using K20 pistons will increase the compression and help you find power... but the F23 connecting rod is really weak and is not designed to rev to 8000 rpm. The H23 connecting rod is much stronger. Aftermarket F23 connecting rods will eliminate the potential for rod failure, but now you are spending quite a bit of cash to build this Frankenstein G23 engine combination. Remember that the H22 cylinder head doesn't simply bolt on to the F23A block, so even with the proper parts, this is a more complicated build... and for what ? If your answer is to be different... then do it. If you thought it would make more power... you were simply wrong. An H22 or H23 with the same modifications that you would do to a G23 will make the same power... and it will go together much faster and easier.

 

^^ This.

"G22/23" are nothing but a junk amalgamation of parts that shouldn't be put together. They are prone to a lot of issues and never make the same power as a full H series. Unfortunately it's not as simple and straightforward as something like an LS/Vtec which is what a lot of people assume. Just because you can do something doesn't mean you should.

 

They're fine if you really need to be out in the garage tinkering. The only real issue I had was reverse offset of the nippon k20 pistons but internally fine after a summer of beatings.But yeah if I didn't just need a fun project I'd definitely go H23bt

 

Well I guess that settles it, I've already returned the f23 block after reading your guys comments, thanks for preventing a disaster lol. Now time to focus on my H22a4 rebuild