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Holley carb


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Thanks, guess I’ll get a rebuild kit.  Just hate all the vacuum lines and crap in using stock carb.  At times I look at the cost of all the motor stuff. Rebuild, carb, cam., makes me rethink a updated motor swap from an early Hardbody  2.4 but can’t find them here without buying the whole truck!  Plus I’m no motor wiz on electronics or rebuilding a motor

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There is a ported vacuum advance for the distributor, all carbs have this, and on the Hitachi there is a ported EGR vacuum source.... and that's it. Keep the vacuum advance and just disconnect the EGR hose to deactivate it. Or keep the EGR functional. It reduces emissions at part throttle. It's not on at idle or full throttle or if the engine is cold.


Have you seen all the hoses on a KA??? got to be 40 or 50 of them.

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There are only 2 hoses to the base of the carb, vacuum advance and EGR.



Hoses not connected to the carb:

On the air filter is the ATC automatic temperature control. This modulates the air temperature to around 100F all year long mixing warmed air from the hot exhaust and ambient air from in front of the rad. Engine will be tuned for this and will run the same even in freezing weather. The engine always thinks it's June out. Without the ATC you will get carb icing when temperature drops near freezing and it's damp out. You'll loose the ATC and also the sensor to correct for over rich hot idle condition when under hood temperatures are excessive if you go to another carb like a Weber unless you convert the air cleaner to fit it.


Charcoal canister by rad. This stores escaped gas fumes from the tank and California models do have a 3rd hose to the float chamber on the carburetor. When engine is running these vapors are sent to the intake and burned. Prevents escape of hydrocarbons into the atmosphere. Has absolutly NO effect on performance and running.


Fuel shut off. Sensor on inner fender detects excessive intake vacuum on high RPM deceleration with throttle closed and transmission in gear, clutch engaged and turns off the idle mixture using the idle cut solenoid. Saves gas and has zero effect on running.


Anti backfire valve. Detects excessive manifold vacuum opens and bleeds vacuum in the intake to reduce oil consumption past rings and an over lean condition during deceleration. Only active on some deceleration, no effect on performance.


Air pump assy. Injects oxygen rich air near exhaust valve to allow burning of hydrocarbon emissions. Draws less power than an alternator but otherwise has no effect on running.


PCV valve. Uses a small amount of intake vacuum to suck fuel and water vapors plus combustion blow by from the crank case through the block vent pipe. The vapors removed are replaced by filtered air from the air filter to the valve cover by a hose. Engine lasts twice as long as without, oil stays cleaner. Has no effect on running.


Automatic choke. Actually an emissions reducing device. It reliably turns the choke off and on and isn't random or forgetful like it's owner.


Back then the emissions controls didn't prevent much. Perhaps the EGR a little. Mostly they cleaned up what was made. Unlike to-days cars that the computer prevents from going into any condition that causes emissions in the first place.

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True enough. The biggest problem with emissions systems is lack of maintenance... usually a cracked hose and this causes problems. Next is an owner that rips out the 'emissions crap' and wonders why it doesn't run right after. Last is a previous owner than has tampered with it before you get it. Figure out how they work and you'll know how to keep them working, or at least how to delete or deactivate them properly.

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I forced myself to become adept at that sort of thing years ago. Adapt or die kind of thing.


When I wanted to de-smog the 22RE in my Land Rover, I learned the systems, followed each vacuum tube/hose, then deleted as necessary. I ended up keeping the EGR, but everything else was deleted.

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