Honda Civic ECU swap
Honda Civic ECU swap
I'm...... not really sure where this goes. It's complicated, but it's not. Just.... stick with me on this
First of all, I'm the owner of a 2000 Honda Civic EX with a 5 Speed and 200,000 miles. It's currently sitting in my garage, awaiting a new crush washer for the oil drain plug and a new cat-back exhaust after the old one broke and tore itself off the car. That's not the car at the center of this discussion, however.
I'm also the owner of a very fine example of 1986 Volvo 240. That car is the center of the discussion. As I said, stick with me.
Strictly speaking, my goal is to perform a Volvo B230F swap into a Honda Civic. That's effectively what I want to do. See, my Volvo 240 is controlled by a set of 2 ECU's, an ignition computer and a fuel injection computer. The ICU is pretty basic, and the ECU is limited to 6200, but more importantly, the ECU does batch fire fuel injection. This hinders performance at low speeds, since the fuel doesn't atomise as well as it waits to be sucked in. So..... I want to install a 1996-1998 Honda Civic ECU into my Volvo. It's the most advanced ECU I can think of that wouldn't require switching everything over to electronic, and those years have OBD2a, which will allow for flashing/tuning.
This is where I would like some kind of guidance. From what I've gathered, I would need a MAP sensor, TPS sensor, O2 sensor, and a distributor, with a water temp sensor being ideal but technically optional. I could either use the stock Volvo throttle body and adapt it to fit everything, but I'm almost certain it'll be easier to make an adapter to mount the Honda throttle body onto the intake manifold.
Questions:
1. The crank sensor isn't required unless I want to detect misfire, right? If I did decide to keep crank position, is there a certain expectation of how much teeth should be on the flywheel?
2. What voltage does the Honda Civic temperature sensor operate at for each temperature? I've tried to find a datasheet for it, but I'm unable.
3. Will the ECU complain if it doesn't have a speed signal?
I'm sure I have more questions, but I can't think of anymore at the moment. I'll not be asking any questions about Volvo systems, the only questions I have is about the Honda, considering all the systems need to be transplanted over from one. Because all my questions are about the Honda side, I hope this is sufficient to let me ask my tech questions here?
First of all, I'm the owner of a 2000 Honda Civic EX with a 5 Speed and 200,000 miles. It's currently sitting in my garage, awaiting a new crush washer for the oil drain plug and a new cat-back exhaust after the old one broke and tore itself off the car. That's not the car at the center of this discussion, however.
I'm also the owner of a very fine example of 1986 Volvo 240. That car is the center of the discussion. As I said, stick with me.
Strictly speaking, my goal is to perform a Volvo B230F swap into a Honda Civic. That's effectively what I want to do. See, my Volvo 240 is controlled by a set of 2 ECU's, an ignition computer and a fuel injection computer. The ICU is pretty basic, and the ECU is limited to 6200, but more importantly, the ECU does batch fire fuel injection. This hinders performance at low speeds, since the fuel doesn't atomise as well as it waits to be sucked in. So..... I want to install a 1996-1998 Honda Civic ECU into my Volvo. It's the most advanced ECU I can think of that wouldn't require switching everything over to electronic, and those years have OBD2a, which will allow for flashing/tuning.
This is where I would like some kind of guidance. From what I've gathered, I would need a MAP sensor, TPS sensor, O2 sensor, and a distributor, with a water temp sensor being ideal but technically optional. I could either use the stock Volvo throttle body and adapt it to fit everything, but I'm almost certain it'll be easier to make an adapter to mount the Honda throttle body onto the intake manifold.
Questions:
1. The crank sensor isn't required unless I want to detect misfire, right? If I did decide to keep crank position, is there a certain expectation of how much teeth should be on the flywheel?
2. What voltage does the Honda Civic temperature sensor operate at for each temperature? I've tried to find a datasheet for it, but I'm unable.
3. Will the ECU complain if it doesn't have a speed signal?
I'm sure I have more questions, but I can't think of anymore at the moment. I'll not be asking any questions about Volvo systems, the only questions I have is about the Honda, considering all the systems need to be transplanted over from one. Because all my questions are about the Honda side, I hope this is sufficient to let me ask my tech questions here?
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Re: Honda Civic ECU swap
Volvo 240 engine specs: Volvo 240 Sedan (244) 2.3 Spec
This engine produces a maximum power of 116 PS (114 bhp - 85 kW) at 5100 rpm and a maximum torque of 192 Nm (141 lb. ft) at 3000 rpm. The power is transmitted to the road by the rear wheel drive (RWD) with a 5 speed Manual gearbox.
So you want to swap one slow turd engine for another that will most likely create complications?
Just throw a B20 high compression Vtec long block and correlating Honda/Acura or a tuner's (such as Phearable) ECU and get a good wide band tune.
This engine produces a maximum power of 116 PS (114 bhp - 85 kW) at 5100 rpm and a maximum torque of 192 Nm (141 lb. ft) at 3000 rpm. The power is transmitted to the road by the rear wheel drive (RWD) with a 5 speed Manual gearbox.
So you want to swap one slow turd engine for another that will most likely create complications?
Just throw a B20 high compression Vtec long block and correlating Honda/Acura or a tuner's (such as Phearable) ECU and get a good wide band tune.
Re: Honda Civic ECU swap
As I've said, a B230F swap is what I'm effectively doing, since that's what the ECU will be 'thinking'. I'm taking a 6th Gen Civic ECU and seeing if it can't be adapted to work on the Volvo for more advanced injection and ignition control.
I'm not sure where else do go, since I'm looking for info on the Honda sensors to see what would need to be changed, what can stay, and what can be dumped.
Side note: Say what you will about the engine being a slow turd, as it is this 34 year old jump of Swedish cast iron can push the car to over 100mph. It's still solid with full compression, so I'm staying with this engine.
I'm just looking for guidance on the Honda ECU side of things.
I'm not sure where else do go, since I'm looking for info on the Honda sensors to see what would need to be changed, what can stay, and what can be dumped.
Side note: Say what you will about the engine being a slow turd, as it is this 34 year old jump of Swedish cast iron can push the car to over 100mph. It's still solid with full compression, so I'm staying with this engine.
I'm just looking for guidance on the Honda ECU side of things.
Last edited by Smorgesborg; Feb 2, 2020 at 08:15 PM. Reason: added year to Honda ECU in second sentence.
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Re: Honda Civic ECU swap
I owned two Volvo 240 road tanks back in the 90's. Reliable car and engine but a 1 minute quarter mile (lol) doesn't stiffen the wood of excitement. I hope your build works out for you.
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Re: Honda Civic ECU swap
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