Zenith INAT vacuum tubing

Keith912

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Hi, I have fitted rebuilt carbs to my 2500 and wondered if there is a correct way for the tubing to go. I have tee'd the sparkplug side of the carbs together and taken to the distributor and tee'd the other side to the air filter housing? Best Keith
 

Stevehose

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I would connect the other side to each other and skip the air is will act as a balance tube and can offer smoother idling.
 

Keith912

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Connect one side of the carb to the other and don't use any tubing to the distributor or air filter?
 

Stevehose

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You can keep the distributor advance tubing. Yes, do a search here for "balance tube" it shows how to connect the other side.
 

Keith912

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Thanks Steve, I have tried a search but get a lot of other info. I think that I need to link the two carbs together and not plug the vacuum to the air filter housing and maybe use only one vacuum port on the other side to the distributor and blank the other one off
 

HB Chris

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If you have a Dizzy with advance and retard hook them both up. Advance port is below the throttle butterfly, retard is above it. Retard hooks to back flat side of vacuum can on Dizzy.
 

Stevehose

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I'd ditch the retard function, along with the speed relays and dashpots it was an emissions move to get the car to run hotter at idle.
 

Keith912

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Thanks very much for all the advice. I am going to connect the left side (your drivers side) of carbs together as balance tube and use one of the other side to the dizzy which only has one port
 

Simufly

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Remember the euro spec cars didnt have all the USA anti smog stuff fitted. Makes them much easier to tune!
 
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