About a year ago I managed to make sense of the vacuum delete posts even with the pictures long gone. I don't plan on keeping this carb much longer, but I figured I would show everyone what I ended up with after months of tinkering. I daily it as you see it and reliability and fuel economy have been good all things considered. You might want to check this thread before you get started: https://www.3geez.com/forum/carburet...ml#post1223619
I will warn you that this carb is extremely hard to tune, in fact there is no adjustment whatsoever. I strongly recommend investing in an air/fuel ratio gauge because without it it is hard to not have a lean idle. Please download the service manual and turn to the carburetor adjustment section as well as look over the original threads Running Keihin 2bbl Carburetor without emissions or electronic contorls.
I will also warn you that messing with your carb and throttle can make your car accelerate out of your control. You will only avoid this with sheer luck or having an inkling of an understanding that overtightening things makes them stick or that air or fuel leaks can do exactly what your right foot can do. Read this whole post and more before you begin.
You don't need very many tools, all you need is some patience or lack there of. You will probably need a welder and some material to make block off plates and plugs, but definitely get some gasket paper. You do not have to delete everything that I did, you can leave things like brake booster, pcv valve, cruise control (in my experience it works if you hook a vacuum line to it, but only if it was already in working order before you start this), that vacuum res on the firewall that goes into the cabin, etc. You do not need any of the vacuum lines that go along the driver side fender well unless you want to try to keep it, AC will work fine too.
First off, remove everything surrounding the carb, and that black box, drop kick it into your nearest dumpster fire. Next remove the carb and MAKE A NEW CARB BASE GASKET NOW. You can begin removing things off the carb and cleaning it out. With your fingers, try to rock the venturis (the grey colored pieces right at the top of the carb barrels) if they have any wiggle then tighten the screws on the passenger side. You might even snug them up a bit anyway, but be careful every screw on this carb is soft. Also, do not remove the accel pump (driver rear corner with a rod that pokes downward as you move the throttle) or any of the stuff on the throttle shafts, most of it does nothing but the important stuff will be loose without taking up the rest of the space on the shafts up.
Now you can take a look at what I have
I really only left one of the extraneous parts of on the carb, no idea what its called, but its dangling off the driver side front corner as you can see. I deemed it too annoying to block off otherwise. No need to remove your pcv valve or anything like I did, unless you want to. For those that do I found a heater hose at the parts store that 90s twice and is short enough to fit on the top of the black box (the pcv one, not the one you just sent to oblivion) without hitting the intake, both ends of the pcv are open atmosphere.
Now you can start to plug the holes. I'm going to dump a bunch of pictures here, I don't have much of an explanation for anything else because we are going bare bones operation, when finished it will just run provided that you don't cause any vacuum leaks. There is no condom here. It will be faster, but it will be crude. Planting your right foot can cause the car to fall on its face before slamming you back in the seat in first gear, it will not level out the idle for the AC, it will be extremely hard to drive cold and even moreso with any accessories running. I have an msd box to remedy all of this.
I will brightly mark everything that needs plugged.
Don't worry about that big glob around my accel pump, my carb is cracked. I still daily it, proof is in the pudding. Vacuum deletes are recommended by 6 and a half out of 10 doctors.
As you can see, one hole is plugged with a screw, two holes on back are looped, one hole, drivermost of the 3 up top on back is the power valve, you want to keep that.
Moving onto the mechanical secondary conversion... As stated in the origional thread this can be dangerous, but if youve done everything above you have no choice. I also don't recall what that "yellow piece" was mentioned in the old thread. It must have been pretty self explanatory, but I will update this part soon. The idea is though, the secondary linkage is two parts, when the old vacuum diaphragm did its thing it pushed the parts together allowing it to open with the primary throttle. We are going to tie those two parts together so that they are locked and the secondaries open every time you bury your right foot. You can see my zip tie that I'm not very proud of, but has lasted so far. The nice part is if it breaks you just don't go fast, nothing bad happens.
Before you put the carb back on pull the plug out of this hole. This is the idle fuel adjustment.
Lastly before you start, run a vacuum line off the big tee right central on the back of the intake and run it to the power valve and the inside port on the distributor. You might notice that the distributor also had a vacuum check valve, leave it. In the pic mine is green and the different colored top points towards the engine. Also run vacuum to whatever else you want still hooked up, some of it you may have not even had to unplug.
Its time to start the car. To adjust the mixture screw on the back, get the car up to temp, unscrew the screw until the idle stops rising, STOP, screw it back in until the idle drops, and STOP. DO NOT FULLY UNSCREW IT. Check your float level, turn the float screw until the fuel is roughly in the middle or upper half of the sight glass, look down the rear barrel and make sure no fuel is leaking from the accel pump jet, it is a pinhole pointing diagonally down into the throat on the top back side, its easy to see it if you rev it slightly with your hand, lower float if its leaking. Turn your idle to roughly 1000rpm then turn on all accessories and check idle again, adjust as necessary. Drive around and check for good performance and no throttle stickage. The spring on the carb are old and sometimes the throttle blades can stay stuck partially open at idle, my secondaries do after a god bit of carb fiddling, loosening the throttle cable and moving the secondary by hand fixes my issues until I mess with it again.
Please help me improve this if I can, I don't want to lead anyone astray as its a very big step in modding your car, totally all or nothing. I currently have another car with the vacuum system mostly in tact I can look back on if you have any questions. Here is an album of the unedited pictures if they help Dropbox - carb - Simplify your life
Edit: I should probably note that your air cleaner will probably restrict you now and you will need to flip the lid or cut the sides off, something to just seal around the filter.
Mechanical secondary conversion: