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Sept. 18, 2011 4:06 p.m. porksboy SuperDork

Any reccomendations for more power in my CRX? It is a 90 DX with the D15B2 engine in it. 5 speed gear box. I want to keep it sane and reliable enough for a daily driver of 35 miles one way. Im officially an old fart and dont want to be constantly repairing the thing. The car is in excellent shape and not riced. It would be a shame to hack it up but I wouldnt be opposed to a bolt in engine transplant from the same family.

This is my first Japenese car and I dont know what engines belong to what family and interchanges with what, or what head bolts on to give me this, or what ECU does that. Any reading suggestions are welcome. I would like to have about 150 to 200 horsepower and keep the reliability with high 20s to low 30s MPG.

The engine in it is still running strong (185k miles) so I dont have to swap it, so if I can achive my goal with minor mods I'd be happy with that.
Sept. 18, 2011 4:14 p.m. Run_Away Reader

150+hp is going to take a bunch of work, you're looking at B-series DOHC VTEC swaps for that power level. A complete swap from a reputable importer will run over $2k all said and done ( http://hmotorsonline.com/shop/sc2000search.cgi?what=page&item=30002 ). Are you sure you won't be satisfied with ~140hp? That can be done for about half the price, still involves a motor swap but keeps your stock mounts, axles and transmission (if you chose not to upgrade to an Si unit with a 4.25:1 vs 3.88:1 final drive). When you're only starting with 90hp, an extra 50hp is a big change.
Sept. 18, 2011 4:15 p.m. Teh E36 M3 HalfDork

I think our man Dave should show up with recipe for high compression t25 E85 goodness.
Sept. 18, 2011 4:45 p.m. integraguy SuperDork

I used to own a '92 Civic CX that had the 70 hp engine (a D15 unit, tho not sure which one). Just upgrading to the B18A1 from a '92 Integra LS doubled my horsepower. In such a light car, the power is noticeable, yet if you aren't a total A$$ when you drive/foot constantly to the floor, your gas mileage will at least stay the same, and in my case, I think it improved on long trips. On interstate-only trips, 40 mpg was possible with occasional bursts to pass semi-trucks. (Of course, that setup also had a CAI added to it, as well as a DC Sports header and free-flow / cat back exhaust.)

If you stay with the B18A, transplant expenses will be "minimal". In my case, I transplanted the engine and manual transmission, along with the 14 inch wheels/tires from the Integra. You can, however, depending on your funds, go up the "chain" to a B18B, a B18C, a B20, a F22, a H22 or H23. In stock form, these engines are more powerful the bigger the displacement/higher the "number".

If you want to keep it close to stock, there is a procedure for changing from your single injector in a throttle body to a more complex/sophisticated port injector. Unfortunately, the non-functioning search function on GRM makes directing you to that thread difficult. If you just change injectors, add a CAI, and a header with free-flow exhaust you could see an improvement in power and fuel economy with your present engine....just not in the range or 150-200 horsepower.
Sept. 18, 2011 5:13 p.m. porksboy SuperDork

I would "settle" for 130 to 140 hp. Thats probably double what I have now. I have a cat back exhaust on it now. 2" pipe with a Flowmaster on it. Cat is intact and NOT gutted. I still have emissions on it for the next 4 years.
Sept. 18, 2011 5:47 p.m. Run_Away Reader

With your current engine you could swap to MPFI (multiport injection vs your throttle body injection), add a decent header, filter-on-a-stick and do a small cam, will net you about 120hp I'd guess but that's about it without going to a cam that will hurt driveability and mileage or raising your compression.

An MPFI swap is the first step in pretty much anything power related with your car right now actually, so you might want to research on that. Google will turn up dozens of how-tos, but it's all the same basically. If you're swapping motors you'll save yourself from buying a distributor and fully dressed intake manifold (assuming you buy a dressed motor and not a longblock) but you'll still need a throttle cable from an Si and to add 4 wires to your engine harness (2 injectors and 2 for the extra sensor in the distributor) along with switching a few pins at your ECU connector and switching distributor plugs.

I had a '90 Civic DX I did all of the above with. I ended up with a D16A6 block, D16Z6 head and Si transmission with knockoff header and cobbled together exahust that was good for 15.2 @ 90mph in the quarter mile. That setup is known as a "mini-me" - what you're doing is adding a VTEC head to a non-VTEC block which results in higher compression than a factory VTEC motor. The factory VTEC motor was rated at 127hp with 9.2:1 compression and mine was virtually identical to the stock motor only with 10:1 compression....I'd estimate around 135hp?
Sept. 18, 2011 6:28 p.m. corytate Reader

kid at school did a d16 non vtec, boosted it to 8 psi and tuned it really well with supporting mods, got 200whp
Sept. 18, 2011 8:23 p.m. Vigo Dork

With these mild goals i think the big decision is: turbo the stock motor, or swap in another one with a better top end?

There's definitely no need to do both.
Sept. 18, 2011 8:24 p.m. wbjones SuperDork

B16 w/type R cams ~ 175 to the wheels ... a lady that track days with me has that in a mid-90's DX ...
Sept. 19, 2011 8:53 a.m. 92CelicaHalfTrac SuperDork

B18B block, Civic Type R pistons (can get them from honda for cheap), GSR rods, GSR crank. B16 head w/ Civic Type R valvesprings, and Integra Type R cams.

Enjoy making 200whp, and revving to the moon.
Sept. 19, 2011 9:17 a.m. porksboy SuperDork

92CelicaHalfTrac wrote:

B18B block, Civic Type R pistons (can get them from honda for cheap), GSR rods, GSR crank. B16 head w/ Civic Type R valvesprings, and Integra Type R cams.

Enjoy making 200whp, and revving to the moon.

Tell me about cost and reliability. What about economy? I know it is up to me to keep my foot out of it. What injection system and related electronics?
Sept. 19, 2011 9:31 a.m. 92CelicaHalfTrac SuperDork

porksboy wrote:

92CelicaHalfTrac wrote:

B18B block, Civic Type R pistons (can get them from honda for cheap), GSR rods, GSR crank. B16 head w/ Civic Type R valvesprings, and Integra Type R cams.

Enjoy making 200whp, and revving to the moon.

Tell me about cost and reliability. What about economy? I know it is up to me to keep my foot out of it. What injection system and related electronics?

Reliability is great! Economy will depend more on what transmission you pair with it. With a tight transmission (B16), you'll probably be spinning 4000rpms on the highway, but should still have no problem getting in the 30s.

Cost... let me check around, i haven't seen this particular build in a while.

You'd use a "chipped" P28 ECU or similar, you'd have to tune it. Would use any "B-series" injection system.
Sept. 20, 2011 10:36 p.m. Run_Away Reader

It's a good combo, but I'd suggest using Integra Type R pistons, not Civic Type R. The exact setup 92CelicaHalfTrac posted results in 13.7:1 compression - a bunch to high for a daily driver, you'd be further ahead with lower compression pistons so you could actually have some timing advance.

Cost wise -
B18B complete motor - $200?
New pistons with rings - ~$200, check out RS Machine they make OEM Honda sized/shaped pistons for cheap and have an excellent track record. Google them if you'd like.
GSR rods - No idea, $50?
GSR crank - ~$100 I've seen locally when they show up, getting rarer
B16 head - ~$500 complete with distributor, intake manifold and VTEC solenoid
ITR cams with springs - ~$400
B16 or GSR transmission - Regular integra trans $200? A B16 or B17 cable clutch transmission is hard to come by now, you might have better luck swapping shorter gearing from a newer hydraulic clutch transmission into the older casing. Shorter ratio hydraulic clutch transmissions are more plentiful but pricier, you can use them but requires a conversion bracket - again, more $$.
LS-VTEC kit - ~$250 you need this to convert the non-vtec block to mate with the VTEC head. Includes stepped dowel pins, tap, oil feed line, oil filter sandwich adapter, plug, and a headgasket.
Motor mounts - ~$200 used?
Plus another $300 in misc new oil pump, water pump, timing belt, bearings, gaskets, etc etc etc
You'll need to cut and weld your shift rods or buy aftermarket ones too. I'm not sure what B-swapped EF's use for axles, stock might work. Single cam radiators have smaller diameter inlets/outlets so you can either work the smaller hoses onto the B series motor or swap in a larger 90-93 Integra radiator.

As you can see, building a whole new setup from scratch can be pricey, the complete swaps appear to be too much at first but when you factor in all the nickle and dime stuff they're worth it. Your best bet cost wise is to find an already swapped car with a rough body and part it out, keeping the drivetrain for yourself.
Sept. 20, 2011 10:46 p.m. Vigo Dork

Or turbo the stock motor for 1/3 to 1/2 that price. Jeez.

I dont think we should seriously be trying to sell someone on a $2000+ mod scheme to get to 150-200hp.
Sept. 20, 2011 10:53 p.m. TRoglodyte HalfDork

GRM sticker is 15 ponies, verified by reliable sources. Buy yours today!
Sept. 20, 2011 11:11 p.m. Run_Away Reader

Turbo the stock motor is probably cheaper and more powerful but you'll be pushing the stock motor near it's limits. D16s "safe" limit is said to be around 225whp then you start bending rods, D15s are weaker than D16s. Cost vs reliability trade-off IMO. IIRC DILYSI Dave bent his rods under the 200whp mark, but he was making more torque than most.

A stock B20 from a CRV with a B16/B17 transmission would be a fun combo. 126hp/147hp depending on the year but lots of twist and tight gearing. Whacking 0.040" off the head would be a nice bump for the price of machining and a headgasket.
Sept. 21, 2011 6:45 a.m. Vigo Dork

I dont think 150-200 hp will be pushing it towards its limits. Think of it as 130-180whp. Also, that car would feel fast with that amount of power, especially with turbo torque vs just revving it higher.