Engine Swap Question: B20B vs. stroked B18B

[ahzab33]

Has anyone swapped a B20B into an 88-91 Civic or know anyone who has? If so, can you tell my what you think of this swap vs. other swap choices like the B18B? I'm torn between the B20B and the B18B, which I can later stroke to 2.0L - 2.26L. The engines cost about the same. The B18B has more HP, but i'm willing to take more low-end torque over more high-end horsepower. The stroker kit from crower costs about $2299 (forged crank, pistons, rods).

Will this engine bolt in using the hasport B-Series mounts? What about the ECU? What ECU choices do I have? Any advise will be greatly appreciated.

[91civicDXdude]

i've said it a million times. if you want "low end torque" then buy a v8. hondas make power in the high rpm. all you're doing by wanting low end torque is killing your opportunity to make real power.

[ahzab33]

Originally Posted by 91civicDXdude

i've said it a million times. if you want "low end torque" then buy a v8. hondas make power in the high rpm. all you're doing by wanting low end torque is killing your opportunity to make real power.

Have you ever heard of the saying "There's no replacement for displacement"? It's true. There is more than one way to make "real power". One way is through higher rpms and the other is through increasing torque. Torque and RPM both play an equally important role in making horsepower, but effect where the engine makes the power differently.

The equation is like this:

HP = torque x rpm / 5252

Therefore 160 HP can be achieved by rpm:
ex: 111 ft-lbs x 7600 / 5252 = 160 HP

or by more torque:
ex: 130 ft-lbs x 6500 / 5252 = 160 HP

Assuming all else the same between these two engines, the bigger displacement engine will out perform the higher revving engine. It doesn't have to work as hard to produce the same amount of power and it reaches its peak earlier which makes the power more useful. With more torque we don't have to rev the engine as high in order to make big power. Increase torque, you increase hp. To increase torque, you increase displacement. With more displacement, you can breathe more air. With more air, you can burn more fuel. The more fuel you can burn per rpm, the more power you can maker per rpm. For a good example, compare an H22 prelude engine to a B18C/B16A. High revving engines can lead to shorter engine life and high maintenance (RX-7 anyone?). Not only does bigger displacement mean slower moving parts, but it also means a better throttle response.

With this kind of power, you will blow past many smaller displacement VTECs. You add a turbo to the equation, you'll be smoking vettes off the line and down the track. Its not peak power we're concerned with, it's the area under the curve where we spend most of our time. What's the good of having 300 HP peak power if it only kicks from 7000-7600 rpm?

[alexdog69]

the b18b and b20 have the same stroke

the b20 just has 84mm bores while the b18 has 81mm

the b18c has a shorter stroke and slightly less displacement than the b18b but they're both still called 1.8L

if you get a b16 and sleeve it to 84mm ok and you will have a 1.8L that will rev like a motorcycle

and since you can get it in OBD-0 you can swap it into your car easier

[alexdog69]

89 x 84 with a VTEC head and some maniac gunning it to 8500 RPM's will most likely blow up after a little while ... especially if you increase the compression while neglecting to add at least a GSR crank girdle and balance the bottom end

[alexdog69]

Originally Posted by ahzab33

High revving engines can lead to shorter engine life and high maintenance (RX-7 anyone?). Not only does bigger displacement mean slower moving parts, ....

Well ...

Longer stroke = Higher piston velocity at the same RPM

and in this particular motor, the LS/CRV crank fucks up the geometry as the rod:stroke ratio goes out of whack in comparison to the original B-series design ... the b16a, which exibits a near-perfect 1.74 r:s ratio..

what does this mean? more side loading of the piston. more pressure on your already weak thin walls bored out to 84mm. this means your motor will break if you are pushing it too hard with high RPMs and high CRs

All that said.. CRVTEC/LSVTEC 2.0 is one bad ass fucking engine when its BUILT PROPERLY..... you can get 220-240 HP and ~150 torque from like 2.5k - 7k... IF YOU BUILD IT PROPERLY which costs $$$

and you wont need to rev it as high as a fully built b18c or b16a in terms of both red line (the power dies off sooner due to the long stroke) and the rpm's you will hit when cruising (with so much torque u can shift sooner and putt around with a numerically lower geared tranny and not be forced to cruise on the highway at 95 billion RPM)..

so, yes, it can potentially mean slower moving parts.. but its not that simple.. adding stroke and bore stresses a motor out.. more stroke = less rpm potential but also gives u more torque... more bore = more power .... but also harder to cool and keep the sleeves intact...

as for ECU if you want to be proper you will need to go ZDYNE, TurboEdit, OBD-1 conversion (Hondata, Uber, Crome, etc) etc.. i.e. custom.. like i said, that is If you want it to be tuned PROPERLY...so you can have the proper air fuel ratios / timing curves and have the motor last a long time....

on the other hand you CAN hack something together ... lots of people do it .. i.e. run a stock VTEC ECU with a stock CRV bottom end with a VTEC head on it ... with FPR and/or piggyback computer...you get the idea... slap it together and drive it around for the summer and have a good time..

i dont know how long that will last however

now .. if u properly build a 2.0L VTEC .. and u put a turbo .. well then u ... well.. u will be my hero... and u are probably very rich in the first place... and u will be putting down ridiculous numbers such that you will be very scared to hit WOT

[ahzab33]

Actually, I forgot to mention that i'm not going CRVTEC. I plan to use basic bolt-on mods with boost on a reinforced bottom-end. As for rpms, I don't plan to push it past 7000 rpms. I want to make my power where it really matters, 3500 - 6500 rpms. Bigger displacement will give you that. Bigger displacement engines respond differently to mods than high strung engines do. With bigger displacement, expect to see more torque gains than you would on a B16/B18C VTEC. I like the CRVTEC because of it's natural torque and it's low compression pistons (8.8:1). I think it would make a perfect turbo project. As for VTEC, i'll pass thanks.

[ahzab33]

Originally Posted by ahzab33

I like the CRVTEC because of it's natural torque and it's low compression pistons (8.8:1). I think it would make a perfect turbo project. As for VTEC, i'll pass thanks.

I meant I like the B20B because of it's natural torque and it's low compression pistons (8.8:1). I think it would make a perfect turbo project. As for VTEC, i'll pass thanks.

[SiZ]

A boosted B16.

[alexdog69]

well if u want NA then u can drop a stock B20Z in there with a cable LS tranny and call it a day .. maybe with LS OBD-0 ECU/distributor/injectors

it should be great, last longer than it will in a CRV and be nice and torquey

but if u do want turbo then B20B is better due to lower compression..

low revving turbo b20b with a tall geared tranny/17" wheels seems like it would be kinda fun to drive on the street =)

ive heard that the stock 84mm bore honda sleeve is pretty weak tho and easily broken ..

[Killa_CRX]

Quoting yourself? why not just go back and hit 'edit' to your post.

Can you read? As 91civicDXdude originally told you, if you want low end torque, get a V8 mustang or something... even the B20 and B18 make very LITTLE torque by comparison... you can sit here and argue 'there is no replacement for displacement' but by doing that, you really don't belong in here... after all, a lot of people on these forums don't go with the largest engine. A lot of them are tuning D16's... and I myself and even 91civicDXdude have D15's.
Now if you want actual information on tuning whatever engine you may end up chosing, stick around... but if you're going to talk shit about other honda engines, then maybe you shouldn't be doing quite so much talking.
I've never had a single problem with my 'low displacement, high revving' engines. RX7 engine is no comparison to a honda engine because they work totally differently.

[alexdog69]

yeah HONDA is still a motorcycle company at heart

[ahzab33]

Installing a VTEC head from a B16, B17, or B18C engine on to a non-VTEC headed engine is a well known and valid power combination. It's popular it has its own nickname. This swap is called a Frankenstein engine. What makes this combination work is combining the larger displacement B18A1 and B18B1 engines that power Integra LS with the increased airflow of the VTEC head. The result is an engine with excellent low-end torque with high-RPM power. With the introduction of the Honda CRV with its 2.0L B-series engine, a new engine swap became available for Honda and Acura builders. Essentiall its the same approach as that of the Frankenstein engine, only with the CRV engine (B20) you get 2.0 liters of displacement flowing through the hot VTEC head. As this book goes to press this is the hot street combination.

A quote from High-Performance Honda Builder's Handbook, Volume I

I took it out and was supprised on how well it ran. I was coming out of a subdivision and I gave it partial throttle. I was bruning rubber! Shifted to second and I still was burning rubber @ quarter throttle! I then got out on the rual roads and open'd her up. I got rubber in 4th gear! CRAZY!!!

A quote from some dude with a website (http://www.geocities.com/extremeist4...esofparts.html) showing his B20 swap.

Like I said, more low-end torque is the key to more usable horsepower. I never said I didn't like high-end horsepower. What I said was I don't like having to wait until 7000 rpms to see good power. A B20VTEC or B20 turbo will give the best of both worlds, better low-end power and good high-end power as well.

I realize some of you will never agree with this approach and I respect your opinions, but it's plain to see which way the wind is blowing. Honda's new engines are all 2.0L and up. The revs are lower and torque is higher.

K20A2 RSX Type S Engine:
1998cc
4 cyl, 16 valve
DOHC i-VTEC
9.5:1 c.r.
PGM-FI (MPFI)
Direct Fire Ignition
200 bhp @ 7000
142 lb-ft @6000
Redline: 7900 rpm

K20A3 RSX/Civic Si Engine:
1998cc (2.0L)
4 cyl, 16 valve
DOHC i-VTEC
9.5:1 c.r.
PGM-FI (MPFI)
Direct Fire Ignition
160 bhp @ 6600
132 lb-ft @5000
Redline: 6800 rpm

Compare that to the B18C/B16 high-revving engines.

B16A2/A3:
1595cc
4 cyl, 16 valve
DOHC VTEC
10.4:1 c.r.
PGM-FI (MPFI)
160 bhp @ 7600
111 lb-ft @ 7000
Redline: 8200 rpm

B18C1:
1797cc
4 cyl, 16 valve
DOHC VTEC
10.0:1 c.r.
PGM-FI (MPFI)
Dual stage intake
170 bhp @ 7600
128lbs-ft @ 6200
Redline: 8200 rpm 128lbs-ft @ 6200

Okay, now that I hope my point is made, is there anyone who has done these swaps and can tell me how well it's worked for them?

[Killa_CRX]

I personally never said there was anything wrong with larger displacement engines... I simply got pissed off because you were talking about smaller displacement engines not being worth the time of day.
I never said I wouldn't like to have a car with a B20 it in one of these days... just not my car that's going to have the D15 in it. Maybe a B20 sedan though...
I will agree that there is no replacement for displacement... but torque is Not the almighty god of the road.

[ahzab33]

Originally Posted by Killa_CRX

I personally never said there was anything wrong with larger displacement engines... I simply got pissed off because you were talking about smaller displacement engines not being worth the time of day.

I understand. I didn't intend it that way. One thing i've learned in my research on building good street cars is that you gotta have balance. Me personally, I can't be satisfied with a super-high strung engine revving up to 9000 rpms. It's just not my kind of car. If I were building a car for endurance racing where I could see myself in the high-rpm range all the time, low-end torque wouldn't matter much. Take a look at F1 race cars which many people compare the Integra Type R to. Those cars rev up to 10,000 rpms and make a lot of power there because that's where they spend a lot of time. But, for street racing and drag racing it's important to have power down low too.

Street cars spend most of there time somewhere between 3000 and 6500 rpms. So, wouldn't it make sense to build your car to make more power in the rpm range you drive in most? With the B20B turbo setup i'm considering, you would have a car that pulls hard all the way to 4300 rpms just from shear torque, then the turbo (or VTEC if you choose CRVTEC) kicks in and will carry you even further into 7000 rpms. That's serious power!!

Just like any engine, the B20B has its share of flaws, most notably it's sleeves. There are aftermarket sleeves available as well as forged pistons, rods, cranks, block girdles, etc. Everything is available to build this engine into a bulletproof monster. The engine is major cheap on top of that. Around $750 for the long block.