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Discussion Starter · #1 ·
Does anyone know why the CVCC engine was discontinued / replaced? I have an 86 Honda CR-X HF and I'm thinking of getting a CVCC engine for it which was in the model a couple of years earlier. It got much better gas mileage. Wondering why they switched and what the advantages and disadvantages were.
 

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93 4d lx, z6,ported, port matched, compression bumped, balanced, manual swap
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Much lower power than even the hf, finicky carbs, and occasional overheating issues. The intake stacked on top of the exhaust manifold didn't help any of those issues, for all that I had fun with my dad's '83 1500 before it cracked a head. That being said a swap would be rough, axles going to be hard, mounts harder, and just decent quality rebuild parts are scarce.

If you are looking to squeak even more out of your hf think about pulling the head, port matching intake and exhaust manifolds, bumping compression a bit somehow (head milling, piston swapping, thiner head gasket, ect.) And a tuning solution that makes use of a wideband o2 sensor. You could look at something like an hx y5 head as well, roller valvetrain, swirl atomization, and vtecE. LLR tires and aero with minor suspension upgrades net gains in mpg as well.
 

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I worked on those engines when at my first real job which was at at a Honda dealership! We did lots and lots of headgaskets on cars with a just few thousand miles on them- I do not recall if it was a federal level recall but Honda had some sort of warranty program going. It was a long time ago but deep in the fog I seem to remember the issue was solved with a revised headgasket. The CVCC set up used a little rich pre combustion chamber with the sparkplug that had it's own wee intake valve ignited the lean mixture coming in from the much larger primary intake valve. F1 engines use a similar rich pre ignition chamber setup so as usual Honda were doing interesting stuff. The use of CVCC allowed Honda to skip having a catalytic converter but that efficiency required a very complicated carburetor that had a rats nest of vacuum hoses and little actuators fuel circuits thermal sensing pressure yada yada yada- I think N0x requirements and the improvements in fuel injection technology and cost put carbs to an end and killed the CVCC. The vacuum lines had little numbers on them and it was easy to screw it up when working on them.. I was just a dumb kid as were most of the 'mechanics' so there were a couple Honda trained guys there from Japan that who could get the things running right. I went on a test drive with the Japanese guys a couple times and the test route had an awesome long on ramp with 4 corners and soft concrete curbing onto I-5 in Alhambra CA- they flogged the cars merciylessly on that little section sliding around on little Michelin X tires of the era bouncing of the fuel cut using the brakes to control wheel spin. Very willing little motors without much car to haul around and certainly not fast but handled and sounded great! That job was an eye opener into Japanese car culture, how to make a FWD car go, internal combustion engine technology, how incredibly bad dealerships would treat the car owners if the shop manager felt like ripping someone off...
 

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Discussion Starter · #4 ·
Much lower power than even the hf, finicky carbs, and occasional overheating issues. The intake stacked on top of the exhaust manifold didn't help any of those issues, for all that I had fun with my dad's '83 1500 before it cracked a head. That being said a swap would be rough, axles going to be hard, mounts harder, and just decent quality rebuild parts are scarce.

If you are looking to squeak even more out of your hf think about pulling the head, port matching intake and exhaust manifolds, bumping compression a bit somehow (head milling, piston swapping, thiner head gasket, ect.) And a tuning solution that makes use of a wideband o2 sensor. You could look at something like an hx y5 head as well, roller valvetrain, swirl atomization, and vtecE. LLR tires and aero with minor suspension upgrades net gains in mpg as well.

I wouldn't mind doing a vtece but that would require a computer and fuel injection which would also require a new gas tank fuel pump Etc. My HF is carbureted. The 84 had the cvcc engine I didn't know that much had changed from the 84 to the 86.

I worked on those engines when at my first real job which was at at a Honda dealership! We did lots and lots of headgaskets on cars with a just few thousand miles on them- I do not recall if it was a federal level recall but Honda had some sort of warranty program going. It was a long time ago but deep in the fog I seem to remember the issue was solved with a revised headgasket. The CVCC set up used a little rich pre combustion chamber with the sparkplug that had it's own wee intake valve ignited the lean mixture coming in from the much larger primary intake valve. F1 engines use a similar rich pre ignition chamber setup so as usual Honda were doing interesting stuff. The use of CVCC allowed Honda to skip having a catalytic converter but that efficiency required a very complicated carburetor that had a rats nest of vacuum hoses and little actuators fuel circuits thermal sensing pressure yada yada yada- I think N0x requirements and the improvements in fuel injection technology and cost put carbs to an end and killed the CVCC. The vacuum lines had little numbers on them and it was easy to screw it up when working on them.. I was just a dumb kid as were most of the 'mechanics' so there were a couple Honda trained guys there from Japan that who could get the things running right. I went on a test drive with the Japanese guys a couple times and the test route had an awesome long on ramp with 4 corners and soft concrete curbing onto I-5 in Alhambra CA- they flogged the cars merciylessly on that little section sliding around on little Michelin X tires of the era bouncing of the fuel cut using the brakes to control wheel spin. Very willing little motors without much car to haul around and certainly not fast but handled and sounded great! That job was an eye opener into Japanese car culture, how to make a FWD car go, internal combustion engine technology, how incredibly bad dealerships would treat the car owners if the shop manager felt like ripping someone off...
I wonder if you could set up a small fuel injection for the pre Chambers as well as normal fuel injection for the main combustion. You can program them on the computer and get rid of the carburetor. I've heard people claimed to get over 70 miles to the gallon on those 1.3 l cvcc engines. VTEC e I believe uses a very intense swirl with one of the intake valves slightly open to and the main intake wide open which causes more even fuel-air mixture and that's how it gets its fuel economy along with long intake runners to bring the Peak torque down the RPM scale. I wonder if the cvcc is still more efficient than the vtec-e or the HF engines.
 

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93 4d lx, z6,ported, port matched, compression bumped, balanced, manual swap
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Might be a fun way to kill a few years, lol. A tiny tb off a geo metro 3 cylinder 1L feeding pre chambers, some y7 injectors at the runners, a whole lotta dicking with it, and a few weeks of street tuning to fine tune it.
 
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