D15, D16, D17 and Mini-Me swaps
By Parko
#359738 Before I start, yes I did some searching but I couldnt find the anything useful lol.

Ive found some oddities on my '92 EG4 GL, D15B4 Australian model.

First I found the vac lines going to the diaphragm on the autochoke going to some kind of solenoid thingy, then to the vac rail across the intake. Then I found a couple other vac lines coming out of the black monstrosity on the firewall that had been disconnected and plugged. I also found that both vac lines going to the vac advance on the dizzy had been blocked - but the bastard reattached the hoses, so I didnt notice these until I did a coolant change and removed them to better access the thermostat.

I managed to get photos of some other d15b4 engine bays in my area, and did my best to correct the vac lines, but I've not touched the ones to the dizzy yet (dont know why I havent, but I havent). Noticed improvement on cold start and warm idle after fixing the vac lines.

Would there be any reason to block the vacuum advance on the dizzy other than stupidity?

Also I have heard of people deleting the black vac box and carbon canister etc, would there be any benefits besides a perhaps cleaner looking, less cluttered engine bay?

I know the d15b4 is no powerhouse, but would it be worth doing any modifications to the carbys while I have the bonnet up fixing the rest of the shit? It is my daily, so it does need to have some kind of efficiency.
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By teal_dx
#360819 I'm guessing the previous owner didn't really know what they were doing but wanted to try to clean up the engine bay or believed that Honda's engineers didn't know what they were doing when they designed the engine that way.
The truth about Hondas is that everything is there for a reason. Fuel mileage will be lower when you start removing things that the engine was designed to run with.
So I agree that the reason to remove the vacuum on the dizzy was probably stupidity because the owner saw it done on an old hot rod with a built motor and thought it would make his honda faster.
On a stock motor, deleting the black vac box and carbon canister will only hurt fuel economy and possibly performance.
I don't have any info on the carb, as we didn't have them here in the U.S. on 92-95 civic.
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By suspendedHatch
#361335 Disconnecting the vacuum advance on the distributor is utmost laziness and stupidity. The equivalent of replacing the radiator fan switch or VTEC solenoid with a manual switch cut shoddily into the dash.
Also dumb for Honda or any company to continue using old technology just because a particular market is lax on fuel economy and emission standards. I can't imagine it being more profitable, but they must have believed it to be.