Don't get me wring I love my 16, but my job has changed directions a bit and now I'm driving 400+ miles a week, and tearing down the highway at 5000+ rpm's is starting to take its toll. Don't get me wrong I love the sweet sound of VTEC, but now that I'm pretty much working out of my car it's just becoming impractical. Also, another factor is that I'm lucky to pull 25mpg on a good tank.

So what would yall recomend? I'm thinking best for MPG would be something that turns much lower rpms and has more torq. Namely a b20 or b18. Probably go with the LS trans?

Recomendations?

 

Contrary to what you might hear, lower RPMs don't necessarily mean better fuel economy OR longer life. For instance, my B20Z Civic does NOT do better on gas than my B18C5 CRX. And both have endured well over the years. However, there is one advantage to having a non-VTEC motor over a VTEC motor that is particularly important these days: the ability to burn regular fuel. For this reason, you might want to consider doing a B20Z swap with an LS transmission. I have found that this is a good swap for those who are just plain irritated by an engine running at 5000RPM on the highway (even if this doesn't burn excessive gas or destroy the engine). I have also found that going with an LS motor instead of a B20Z saves nothing in terms of gas, while feeling MUCH more limp-wristed in the torque department. So this would seem to be THE swap for you to do. Of course, I would go for the higher compression (9.6:1) B20Z rather than the low compression (8.8:1) B20B. Higher compression both saves gas AND gives you better HP and TQ.

One more thing. If mileage is important to you, BE SURE TO GO OBDI. From my experience, mileage is significantly better with OBDI than OBD0. With your B16A, for instance, you could get your mileage up into the low 30s if you were to ditch OBD0 and go with a USDM P30 ECU. The same is probably true with a B20Z (mine gets about 30-33MPG on the freeway with an OBDI PR4).

 

LS trans would be a good start. You don't really have many options for added torque for cheap. You could always slap on an LS or CRV bottom end but then you'll have to get retuned and all that jazz which adds up quickly.

My vote would be to find someone who locally who will trade you an LS trans for your B16 trans (you could most likely even get cash on top of their LS trans) and see how you like that before spending too much money.

 

Hows the power with the pedal down on the b20z? I'd assume it's going to feel a lot snappier than my b16a, and without having to rev to 6k before making good power? Also, what does a b20/ls roll rpm wise at 70mph?

I'll definitely go to obd1 with the swap. Been thinking about doing it for a while now with hopes of boosting and having better tuning options available. BUT if you're telling me I can burn an extra 50+ miles or so to the tank by converting then I'm definitely SOLD. Dam.. I'm sounding old.

Actually, they're paying me .35 a mile on top of my salary so anything I save in gas goes straight into my pocket.

One more thing, what mods off my 16 would fit and be worth swapping over to a b20? Type-r mani/TB, header. etc?

Thanks,

 

Honestly, a D15B would be a good bang for your buck, but since you are already B series, I'd say a run of the mill LS setup. With good driving techniques, I got my LS with YS1 tranny to yield 13.75 km/L. I'm sure with a LS tranny I could of gotten way more. It's mainly in the driving techniques tho. I got my B16 to get 11.90 km/L.

 

What trans were you using with your 16?

11.9/L is like 1/2 a mpg better than what I'm getting now, and I'm really not pumped about it. Especially for a moto being dropped into a car that's 6-700 pounds lighter than the original car it was rated to get 28mpg in. The 13.75 is much more up my alley at the moment.

Also, I did consider a D series, but it really would'nt make much sense to step back to a lesser series. I'm really thinking a larger displacement - low RPM engine is what I'm after now anyways.

 

I dont know alot about B-series transmissions, but can't you put in a taller 5th gear like the D-series folks do?

 

Wow. I get 33-38 mpg in my rex with a B16A and S1 trans, and thats beating on it most the time too......You have everything tuned up?

I here you talk motor a lot, when the most mileage will be seen in driving style and the transmission you choose. Not the engine.

There isn't a Honda motor out there that wont get 30+ in a CRX.

 

sired91, what obd are you? what tire setup? i'm lucky to get 30mpg on trips with obdo and j1 (i think) trans. i've 205/50r15 z rated tires

 

I still got over 20mpg in my OBD-0 B16A/Y1 CRX when i first got it, beating on it with a leaking headgasket, no IAT, no O2, no knock sensor, and who knows what else was wrong with the hacked up wiring.

 

Well shockingly I just pulled 34mpg or so out of my last tank. I think VTEC is just killing my MPG. It's set at 4450rpm. Drove 250 miles today and I'm sitting just under a half a tank. MPG wise the car seems to like putting around at 60-65 mph down back highways, rather than screaming at 75-80 down the freeway in vtec. I always new VTEC was killing my mpg, but being that I take I-5 everywhere I never got to put more than a handfull of miles on her without being in vtec.

Comparable mpg or not, the 16 just doesnt fit what I need anymore. My phone is practically glued to my ear some days and it's just too akward to take serious business calls when you can barely hear who's on the other end of the line.

Also, the 16 is getting aged and it has seen it's share of track time, so I have quite a few more reasons to swap something new in other than MPG. Powerwise I think I'd really like something that makes power down low. Maybe I'm getting old but I just feel "ricey" raping the bitch past 6k just to get to where the power is at.

SO yeah, in a nutshell I'm looking for less of a race horse, and more of a tamed work horse that'll still giddyup when ya kick it in the nuts.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybridize &raquo;</TD></TR><TR><TD CLASS="quote">Hows the power with the pedal down on the b20z? I'd assume it's going to feel a lot snappier than my b16a, and without having to rev to 6k before making good power? Also, what does a b20/ls roll rpm wise at 70mph?</TD></TR></TABLE>

Actually, the B20Z with an LS transmission is not too bad when you step on it. I've done the B16A thing myself, and actually had both the B16A and B20Z up and running at the same time in different cars. And I would say that the 'get up and go' in fifth gear on the freeway is virtually identical between a B16A and B20Z. So if you go with the B20Z, you are not going to lose anything here - despite the fact that the B20Z only spins about 3300-3400RPM at 70MPH (with LS transmission) vs 4100-4200RPM for the B16A (with B16A transmission). In first gear (where the overall ratio is MUCH more similar between the LS transmission and B16A transmission), there is just no question which one pulls better. Overall, I say go B20Z/LS transmission. You will actually end up with a car that has virtually the same peak HP as a B16A, as well as similar potential acceleration, but which runs at MUCH more civilized RPMs. Go for it!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zrickety &raquo;</TD></TR><TR><TD CLASS="quote">sired91, what obd are you? what tire setup? i'm lucky to get 30mpg on trips with obdo and j1 (i think) trans. i've 205/50r15 z rated tires</TD></TR></TABLE>

OBD0 PR3 Xsi ecu, stock internals...all bolt ons.....S1 tranny
15x6.5 with Nitto NeoGen tires @ 40lbs

 

Why not just get a second car. I see decent DX/LX sedans all over craigslist for under a grand. My EX (With stock D16A6) get 36MPG minimum, the DX/LX can only get better. I only do about 200 Miles a week, and I cant imagine doing that while getting less than 30.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybridize &raquo;</TD></TR><TR><TD CLASS="quote">Well shockingly I just pulled 34mpg or so out of my last tank. I think VTEC is just killing my MPG. It's set at 4450rpm. </TD></TR></TABLE>

Wow 4450 is pretty low... is that stock for a b16? Maybe you should get a tune and bump up that vtec engagement to about 5500-5700.

I understand hating to be at 5k on the freeway... My poormans mans setup is netting me 25-28 MPG mixed driving...but i am not in vtec on the freeway.

 

dunno wha my gas mileage is but i know my mileage is getting eaten up wit my setup...b20b/j1 obd1 pr4

the thing eats gas lol but damn is it torquey im actually doin the ls tranny this week

 

HYBRIDIZE, I had to look up your age man hahahah your a year older then me. Its strange how times change when you get older. I have a b16 hatch also but its not my daily thank goodness. My daily is a 94cx but I had to pull the motor because it was going through 5 quarts of oil a week, no exaggeration. So I swapped in a z6 and did a bunch of maintence to it. My old cx motor used to pull 40-42mpg even while it was literally drinking oil, while my new z6 motor only pulls 33-34mpg. I can't really complain too much the motor runs great but its lacks power. I'm actually thinking about swapping in a B20 also but I don't want my gas mileage to plummet.

Stormin, has a point though. Even though its a larger displacement motor that doesn't mean its going to burn more gas. It all depends on how much work the engine is actually doing. Prime example if your climbing a hill in 4th gear at full throttle but the rpm's stay at 3000rpm, while if you were in 3rd gear at 4000rpm at partial throttle you would burn less gas.

You also have these tuners out here who will lean the hell out of their cars during partial throttle to improve gas mileage. I believe Jeff Evans did it to his vx hatch and was getting 55mpg on the high way if I remember correctly.

 

b18b1 with ls tranny, i bet youll pul close to 40mpg on your crx. my 01 ls gets 36 mph highway cruising at 70mph, @ 70 mph im at 3k rpms. also this combo is has decent torque or you can throw in a gsr tranny, but i dont suggest it since gsr gearing is much shorter than LS, so it would be tough on the engine since it wasnt made to rev as high as a b18c1. not to mention this swap is inexpensive.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TOO MUCH TORQUE &raquo;</TD></TR><TR><TD CLASS="quote">@ 70 mph im at 3k rpms.</TD></TR></TABLE>

The 1994-2001 LS transmission actually has taller gearing than the earlier cable LS transmissions (like I have). However, if you want to use one, then you will either need a hydraulic conversion kit OR need to swap the gearset to a 1992-1993 case. By the way, I didn't like the LS motor. I actually had one before my B20Z, and found it to be, shall we say, gutless. It just didn't seem to have the torque to REALLY pull those gears. And gas mileage was NO BETTER than the B20Z. The bottom line: go B20Z.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DailyDriverCivic &raquo;</TD></TR><TR><TD CLASS="quote">Why not just get a second car. I see decent DX/LX sedans all over craigslist for under a grand. My EX (With stock D16A6) get 36MPG minimum, the DX/LX can only get better. I only do about 200 Miles a week, and I cant imagine doing that while getting less than 30.</TD></TR></TABLE>


You sound like my girlfriend, traitor! EF fo life, yO!

Seriously though, I have thought about it, but the CRZ hasnt went into production yet. No ok, to be honest it has been pondered several times, but I'm not sure I want to go that route. I really do love everything about the CRX, -except, the engine I have in it at this time. I've really been checking out 93-2000ish preludes, the only thing is I hate make payments almost as much as I hate full coverage insurance. A cheap daily doesnt sound bad either, but for the money I'd rather just swap into something that I'll like for the CRX be totally happy and save 1000 bucks.

The more I'm reading about the b20 the more I'm thinking it's for me. Where's the best place to source one?

 

If your only getting 25mpg on a stock b16 in a crx then you either need to change your driving style or something is wrong. My stock b16 w/ S1 trans got 30+mpg consistantly for 8 years without even trying. My cammed b16 even gets 26-27mpg.

If your looking for something quieter at highway speeds then I would agree B20Z/ls trans combo FTW.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Furyof4 &raquo;</TD></TR><TR><TD CLASS="quote">If your only getting 25mpg on a stock b16 in a crx then you either need to change your driving style or something is wrong. My stock b16 w/ S1 trans got 30+mpg consistantly for 8 years without even trying. My cammed b16 even gets 26-27mpg.

If your looking for something quieter at highway speeds then I would agree B20Z/ls trans combo FTW.</TD></TR></TABLE>

Stock as in ALL stock? No headers, intake, exhaust, etc?

I actually have a book that I log my mileage in. I'd say I average about 26-28, and usually fill up approximately every 2 weeks (depending on the amount of driving).
I have OBD0 with custom ram-air intake, full exhaust, Y1 tranny, 7.5lb flywheel, and 205/50/15 tires. Every now and again I manage to break into the 29s/30s.

When I was driving my old 91 DX daily, I believe the lowest mileage I ever logged was 29. By that, I mean ONE TIME. I used to get consistent 32s+ all month long. Man, that brings me back 4 years ago. Every now and again, gas would fall under a buck!

 

Well to clear things up about my engine, it does have some goodies.

ITR mani/tb, ITR intake cam, AEM intake, greddy header, greddy cat back, hollowed cat, MSD 6AL, Blaster coil, fpr. I think that's it... Ehh untuned cam gears as well.

Also running a PR3 ecu running a fake mugen program(vtec at 4450). Which my wideband showed to be suuuper pig rich until I pulled my fuel pressure down to 25psi. Had it somewhat tuned until my Vafc got jacked..


Now for some more questions.. I'm pretty much set on going b20. I really can't see any reason not to. I really don't want to buy one off of ebay, so what's a good source these days? HMO still good?

Also, from doin some research it appears that it could be tricky getting the right b20. Appears the JDM b20b's have specs all over the board. SOme high compression, some low; and that the only way to tell the difference between the 2 is if it has a knock sensor or not. From what I've read the safest bet is to go b20z as its a sure bet to be the higher compression engine.

One other thing.. What parts from the 16 interchange to the b20? Can I keep my header and manifold? From what I remember it's just the GSR head that is different from the rest of the B-series, correct?

 

i don't get it, i have a b16a w/s1 trans in an ef hatch and i get near 40 mpg.
mixed driving style, highway and city. granted it's obd1 and tuned too (i/h/e)

 

What's the speedlimit you're driving at? Turns out I do fine at 65-70 or so, but if I get into vtec my mpg takes a massive dump. Actually I pulled another great tank out of her today at 32mpg. It's crazy, imo, normally I'm happy to pull 260 miles out of a tank. So I'm pretty pumped to be seeing anything over 300.

The thought crossed my mind today to swap the 16 over to obd1 now, and see what I think about it. Atleast that way if I still want to go over to the b20 I can do the swap in an afternoon, and not have to worry about messing with wiring.