My friends and I are planning on doing an engine swap on a Honda CRX DX. I was wondering what aftermarket parts are available if the swap was a B16A JDM Engine? Meaning if whether the DC Sports headers are available for this engine, or even if the AEM Tru-Time Cam gears are available? Is there a specific turbo made for this engine, or is the CRX or the newer Si turbo would fit? Thanks for any help.

 

All B16A engines use B16A cam sprockets, so those are commonly available. The headers for the engine are Del Sol VTEC, but the JDM B16A has two O2 sensors in the downpipe so drilling and welding in a new bung will accomodate the dual O2 sensor setup (alternatively, you disconnect both O2 sensors from the ECU and just leave the 1 in the Del Sol VTEC place so there's no exhaust leaks... I highly recommend doing this).

I think you can use a Drag Gen III kit for a turbo, but I'd get the engine in and running before worrying about that .

 

The jdm B16 is basically the same as the 94-95 Delsol B16 engine.
All the parts made for the delsol will work on the JDM B16.

That does not include the transmission, for it get the parts from a 90-91 Integra.

About wiring, you will have a bit more work since you have to convert from
DPFI (dual point fuel injected, 2 injectors) to MPFI ( multy point fuel injected, 4 injectors) Also you will have to rewire the distributor since the B 16 distributor has an extra sensor the DX does not have. then it's just a matter of adding the extra 4 wires for VTEC to work.

About the O2 sensors, you need them!
if you don't have O2 sensors you will get a check engine light, and the engine will not run in a normal way.

my B16 powerd CRX does the 1/4 mile in 14.2 seconds with full interior.
I have a 65mm throttle body, header with 2 o2 sensors, exhaust and AEM intake.

No check engine light and just under 40 MPG (miles per galon)

George

 

About the O2 sensors: you do NOT need them, I repeat, do NOT need them. In fact, my engine runs WORSE when they're hooked up. This is from experience, on at least two separate B16A-powered CRXs that I know of (elusiveracing23 on this board has the same problem as I, and it was solved by disconnecting the O2 sensors). You WILL get a check engine light periodically, but just ignore it. It goes away when you turn the engine off, and the redline is not affected. Neither is the VTEC engagement, or anything else that I can tell.

 

hey raeneshadow
i know u live out in bc since i am from there
have u tried to go through aircare yet with your car?
what were the results like? did having no 02's hooked up help u pass?

something for me to think about when i get home

 

I haven't tried yet, but when I spoke to the place who sold me the engine, the guy who owns it actually owns a B16A powered CRX. He said that they usually pass, but they've got to be in good working order. That means if your cat's clogged you might have troubles.

In my car, the O2 sensors appear to be hooked up, but I unplugged them from the ECU harness. That way I can still have them hooked up to the Autometer A/F gauge, but the ECU isn't going to see them and start flaking out.

P.S. Passing is as simple as making sure all your emissions stuff is hooked up, and if you've got one, use a B&M adjustable FPR to just turn down your fuel pressure... your engine'll run like crap, but it won't be burning as much fuel so the guys at AirCare won't see excessive HCs or anything .


[Modified by raeneshadow, 5:53 PM 7/24/2001]

 

Thanks for the input. I'll keep the O2 sensors in mind, but my friend is actually putting the engine in for us. I'll keep y'all posted when we do get everything up and running.

 

Hey Raeneshadow.

I understand your engine runs fine without O2 sensors.
Do you know how they work?
Do you know what the ECU does with the signal from the O2 sensors?
Do you know what the ECU does when it doesn't get any O2 sensor signal?
Do you know why your car ran worse when you connected the O2 sensors?

I know.

I HIGHLY recomend against running without O2 sensors, Honda and every other car manufacturer in the world uses them, for a good reason.

This is not a personal attack or anything like that, it's just that what you are recomending is not the right thing to do. sorry.

George

 

I DO know how O2 sensors work... varying narrowband voltage 0-1 V based on the oxygen percentage within the header to the oxygen percentage outside the header (which is why if you touch/coat/mar the outside of an O2 you can wreck it).

I DO know how the ECU takes the signals and uses them. That's obvious.

I DO know what the ECU does when it doesn't receive an O2 signal (it throws a code and uses preprogrammed fuel and timing maps... but not the limp mode maps!!).

I DO understand that Honda sent them from the factory for a reason... that reason is... they're used for fine-tuning... FINE-TUNING... the air/fuel ratio. Therefore, they are NOT necesssary. The fuel and ignition maps are merely modified by the O2 sensor voltage upwards or downwards several percent, not much mind you!... based on other sensor readings. Those other sensors are still used when the car's not in limp mode.

The only difference between running with O2 sensors and running without O2 sensors is that my fuel maps are not being fine-tuned for stoich running. These fuel maps currently in use by my car are, no doubt, tuned slightly richer than is necessary for safe running conditions.

If you know why my car runs worse with the O2 sensors connected, please tell me. Let me give you a breakdown of the problem:
My car runs rich all the time. The only time it does NOT run rich is occasionally during part throttle. Sometimes (when the O2 sensors are connected) at a stoplight one or the other of the O2 sensors will indicate a full lean condition, to the point where the engine's idle is affected. During part throttle, my engine will usually run nearly full lean. With the O2 sensors connected, the #3 and #4 cylinders will lean out to the point of detonation, causing a highly annoying surging, while #1 and #2 will continue running full rich, though occasionally these cylinders will also run full lean. With the O2 sensors disconnected, both banks of cylinders will continue to run at the same air/fuel ratio, hence not causing any surging and/or detonation.

Now, I ask YOU... where did YOU receive your information? Mine was received from various sources, the major one being the man working for Hondata, the company which was first in the industry to crack the Honda ECU programming code. That's right, my O2 sensor info and recommendations are made based on what Hondata recommended to me directly. If you had read the links I posted, you would have known that in fact Hondata does not even bother connecting the O2 sensors in ANY of the engine swaps they do.

Here, I'll post it again: https://honda-tech.com/zerothread?id=50722

And the most important portion:
I'm not trying to rag on you, man... but seriously... that's like telling me I'm doing something wrong when I tried it your way and it didn't work.

 

Have it your way, buddy.

The reason your car ran worse with the O2 sensors connected is because you had them crossed.
the ecu is deisgned to expect and recognize a difference between the 2 O2 sensor
signals.

in the stock manifold each of the O2 sensors monitors 2 cylinders only, swaping the order in which they are supposed to be connected causes the ECU to make the engine hesitate.

I had that problem, swapped the O2 sensors and it works perfect.

I am a Mechanical Engineeer, and did some consulting work for TWM induction
a while back.

http://www.twminduction.com

I specialize in Thermodynamics. Combustion is something I know quite a bit about.

Take care.

 

Hey I did this too, and it did go to a better operation in the low rpm range but feels like the top end isn't there as much. Hey Lunchbox, so your telling me to switch where I have the O2's plugged to the ecu and it will run fine again with the sensors and make the engine run with out the CEL coming on anytime i get over 7800 rpm. Well I will try anything to get the car running right so I will try it. Do you run one of these cars around Orlando area? I'm in maitland and if you do run one of these I would be interested to see it.

 

Hey spaceball where is TWMinduction located?

 

Just curious, so why is it that on the US spec cars that they only run ONE O2 sensor instead of two?

I plan on getting my PR3 reprogrammed to eliminate the second O2 sensor to save a little time on the wiring, and so that I don't have to weld another bung to the aftermarket header I'll be getting when I do the swap.

 

TWMinduction is in Goleta, California.
About the single O2 sensor, Honda used one on the US CRX engines since these
were not high output engines, and one O2 sensor was enough to keep track of the A/F ratio.

On the B16, Honda played it safe by monitoring the engine more closely and decided to run 2 O2 sensors along with a knock sensor. Back then (Honda released the B16 in 1989)
O2 sensors in Hondas were single wire, and they take longer to reach working temeprature. With modern advances in O2 sensors and the use of 4 wire heated
O2 sensors, you only need one.