Alex Ruiz

Need help deciding what to put in my 98 civic. Don't know to go with the h23 or f20b or maybe go b series. I want to be able to smoke kids lol my budget is around 3 or 4gs.

jbpnoman

We aren't going to do your research for you. Wikipedia has the bhp/tq stats for all of those motors, and you can spend 15 minutes figuring out how much each swap will cost you. You'll need mounts, ECU with tuning option, transmission, and adapter plates if you go H2B/F2B.

pjhatchin

Go with the h23 best way to go. They make good power in stock form. Mine made 222 hp and 185 ft pds with intake header exhaust. Go with a QSD h2b kit and pick up at least a b16 trans.

ESP.net

H23V your talking about 30-40 hp difference... 95mm stroke vs what 8x bigger stroke will always make power...

H23V 200 whp 170+ trq range
F20B 170+ whp rangine and 135+ Trq

H23V is only about $300 more and about $300 in parts to get it back to OBD1.

92frostwhtdb2

The only plus I really see to the f20bs are the iron sleeves, other than that why would you choose less displacement given the option? Chances are you'd end up with the 180 crank HP auto version unless ordering from a place like HMO, I just made 217whp 175tq with bolts on */thread*

pjhatchin

The only way u would pick an f20b over and h23a would be if you wanted to bore out the f20 to 87 and do a nice rebuild and wanted to save money on sleeves.

ivan93egreppin210

How safe is it to overboard to 87 on the f20b

pjhatchin

Seems to work. PM rrace002 for more info. He has a thread on doing one.

Libertariat

I've got the H23A with an ITR transmission (MFactory LSD)

The F20B wouldn't hold a candle to the power I make. (207whp, 164ft/lbs with an OEM muffler)

Haven't dyno'd it since I replaced the OEM muffler.

Divers

In stock form the h23 makes more power, but the f20b will out perform the h23 in high power applications.

Libertariat

I assume you mean in turbo applications in particular.

Divers

Yes, but it is relevant to piston speed at high rpm. Extreme NA motors will experience the same thing.

AllMtrRex

I have to disagree even though I know where you're going with the piston speed theory, etc. It may need to be considered if long life/less power is your goal but as far as strictly drag racing, (shorter life/more power) there isn't many builders considering r/s ratios, piston speeds, etc, in today's All motor classes which use mostly OEM deck height, and 105+mm strokes. Pistons can only be shorten so much and wrist pins can only be moved up so much to utilize a longer rod but neither is enough to create and ideal piston speed, r/s ratio in those kind of setups.

There are 9-10 second 4 cylinder all motor cars that are utilizing stock deck height and making huge power, while lasting a respectable amount of hits.

Some disagree with me here but I'd take a 100mm(H22 Stroker) stroke x 89mm bore (sleeved) setup any day over a 88mm(F20B) stroke x 89mm bore (sleeved) setup. Granted, I'm talking NA Drag Race Application.

I just don't believe the 88 stroke setup could make the same power or tq given both setups share the same cylinder head, header, intake, fuel combination. Additionally, I feel if each setup had a specifically designed custom made header, intake and cylinder head (Not a theoretically designed head, that hasn't been done or isn't possible on an OEM cast head), I still think the smaller stroke would lose out but may last X amount of hits longer.

Divers

The All motor guys must rely on displacement and the only place to grow it is in stroke. That doesn't make it ideal, its just makes it the best with what you have to work with. In turbo applications, we have a "replacement for displacement" but it does no good if we reach a point where the piston is out running the boom. The fast b-series guys are on gsr cranks, not LS and we switched from a h22 to a f20b. None of us destroked our engines for ***** and giggles.

If the all motor guys were able to achieve the bigger displacement with bore instead of stroke they would.

AllMtrRex

Andy, I agree with what your saying but in N/A form there is no "replacement for displacement". It would be nice to go bigger bore, yes, and it would be nice to have taller decks (other than custom deck plates) to fit longer rods and same goes for raising the pin on a piston before it's unreliable. They're all great wishes, but in my opinion, in N/A form, (stock or race spec) with OEM deck height limitations, cylinder bore limitations, and cylinder head limitations the F20B will not outperform an H23V because of design limitations.

If a custom billet block was designed to allow larger than 90mm bore for the H/F crowd I still do not see a 88 stroke making more power in N/A form than a 100mm stroke with the same available "custom block". There would likely have to be a custom cylinder head with custom rockers to take advantage of the longer rod setup for the F20B to see significant advantages. Get where I'm goin?

92frostwhtdb2

You guys are taking this discussion in engine dynamics way past the 3-4k budget this guy is working with..its always good to hear actual ”tech” debates but in regards to this thread it's irrelevant..point is in STOCK or close to STOCK form which engine will produce better performance #s Answer is simple: h23a

bluehbcivic

why the f would a f20b make more power over an H23A ?! I mean...

256CC more for the H23 caused by 2mm more in bore + 7mm stroke
has 1mm bigger valves meaning better airflow<<power

bluehbcivic

Libertariat

Well said. The discussion is badass, but out of context.

rogerdarnell054

What about I'm running a f20b head and a h23a1 block..what head gasket do you use?

96accordnibba

one possible advantage of the f20 is its high rev range that allows better boost and better use of lower gear ratios