HEATED 4 BBL INTAKE

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A/MP

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Clifford or Offy had an intake that was preheated by water from the radiator. Did it make any difference?
 
it should in cold weather. 60-70 high humidity can ice a carb too. probably not a factor in Florida....
 
Clifford or Offy had an intake that was preheated by water from the radiator. Did it make any difference?

Clifford has a built in plenum, and absolutely it works.
It actually works in 2 ways. It heats the carb to operating temp, and also keeps it from getting to hot. It will keep the carb and intake right around the temperature of the coolant.
Works well.
 
I looked at the Clifford site and it only shows a 2bbl intake. There pic does show anything about a water hook up.
 
I recall a plate between carb and manifold that fords used many moons ago.had heater hoses connected to it. Wonder if an enterprising individual could flange something up??
 
This...
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^^Ford 4 bl heated spacer. You might find them on Egag etc
 
Don't use a heated spacer. You want the intake manifold to have a hot spot on the floor of the intake manifold and the carburetor to be as cool as possible. Heating the carburetor leads to percolation. See Intake Manifold Heat and Vapor Lock.
 
I dont think the coolant would bring the carb up to percolation temperatures as the carb is somewhat self cooling when running. oyu want to add heat when running, exhaust is the fastest heat you can get short of an electric carb heater.
 
It's better to insulate the carburetor from the intake manifold than to heat it.
 
I dont think the coolant would bring the carb up to percolation temperatures as the carb is somewhat self cooling when running. oyu want to add heat when running, exhaust is the fastest heat you can get short of an electric carb heater.
I somewhat agree. But up here, when temps are in the low 60’s and humidity is high frost will form in the carb. I have seen it.
But the solution is the warm air intake built into the air cleaner.
The time it takes to warm the coolant from cold start will still allow the frost to form.
Seems 4bbl carbs are less succeptible to this.once engine is at operating temp,the frost is rarely an issue
 
I used one of those Ford plates on my Cliiford intake. Works great with a 1/4" insolator. Just like Ford designed it back in 1965. I also have a 2v version.
 
i read that having the fuel the same temp as the engine helped produce more low end power. but i feel that having an electric fan on the radiator will help it fill fuel boiling after shut off cause the coolant temp rises after shut off and fan will stay on until it is cooled
 
Clifford intakes are the ones with the water passage built into the bottom side. I believe they made them both ways, with or without the water jacket so you'd want to verify which one you are buying. An Offy has a spot to bolt on the original heat riser from the exhaust, which does the same thing but quicker than waiting for the coolant to come up to temp. The Offy also works with the Dutra Dual setup, a very good upgrade. For most of us not living in a hot environment (say, from AZ to FL) some kind of intake heat is a real benefit for good street manners. The heat keeps the atomized fuel from hitting the floor of the manifold and turning back into liquid.

If someone had a reason to want an Offy and either headers or dual Dutra Duals (meaning no exhaust heat riser available) there is a guy on eBay selling a riser block-off plate for about $15 or so. I got one with the intent to tap it for hose fittings and make it work like the water jacket on a Clifford. Also, Aussie Speed sells a similar gizmo, it's a little box that's already tapped for pipe fittings. You attach it to the bottom of your manifold and get the water heat that way. It's a little more at about $60 or so but a slick solution if you need it.
 
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