Manifold Heater for Cold Climates

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cchrishefish

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I purchased an Aussiespeed Hurricane intake and a manifold heater. The heater has two 3/8 inch threaded holes on one end and 1 threaded hole on the opposite end. I want to tap into the heater hoses. From what I understand, I can install some type of threaded heat tap that shuts off the coolant flow at a certain temperature. I need some guidance on how I should hook it up, should I use brass or steel fittings ETC? Part numbers would be helpful. I never heard of a heater tap, is it a fitting with some thermostatic control built in? AS0112 Universal Plenum water heater box for intake manifold | Aussiespeed Street & Racing Products Australia

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Before getting concerned over being able to turn off the hot water to the carb base, I would install the intake and hot water box and run it.
My guess is the long runners on the AS intakes will like a warm carb base to keep the fuel in suspension at all times.
Hot water heat on an intake will max out 190 to 210 depending upon the thermostat. That is much less than the radiant heat that will be hitting the sides of the intake runners from the header flanges.
 
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I would just plumb it in and run it. Coolant is much more stable as a heat source than exhaust heat ever was, and runs cooler under many "hot weather" running conditions than exhaust heat would have. Ford, years ago, used water heated carb bases on their V8s with no temp regulation.

If your heater uses a water valve of some sort, you will have to use "Y" or "T" fittings instead of inline or series.
 
Before getting concerned over being able to turn off the hot water to the carb base, I would install the intake and run it.
My guess is the long runners on the AS intakes will like a warm carb base to keep the fuel in suspension.
Hot water heat on an intake will max out 190 to 210 depending upon the thermostat. That is much less than the radiant heat that will be hitting the sides of the intake runners from the header flanges.
A member from Aussiespeed just informed me to block off the third tapped hole in the manifold heater. They put it there in order to install a heat sending unit ETC. Therefore, I believe a tap into either of the two heater hoses will work out fine. I did see someone tap into the water pump hose, or a thermostat housing. But, this may not be the best option for a slant in order to make the install look good. I believe the heater hose would allow for the cleanest install.
 
A member from Aussiespeed just informed me to block off the third tapped hole in the manifold heater. They put it there in order to install a heat sending unit ETC. Therefore, I believe a tap into either of the two heater hoses will work out fine. I did see someone tap into the water pump hose, or a thermostat housing. But, this may not be the best option for a slant in order to make the install look good. I believe the heater hose would allow for the cleanest install.
I have water heat on a super six intake that I have on my ‘83 D150 / Slant with Dual Dutra’s.
I converted the EGR cavity on the bottom side of the intake into a sealed water chamber by using a steel plate as a cover on the bottom side. There is a second steel plate on the out side. Each plate has a fitting taped into it. I used hard 3/8 tubing as the water lines. My 83 head had an unused sensor hole on the top side near the thermostat housing ( was used for a Lean Burn sensor) that became the water out to the chamber. For the water return I T’d into the heater hose that returned water with the T near the water pump. The lines that I used is the formable brake line sections available at auto parts shops.
Don’t get me wrong, heater hose T’d into the regular heater hoses would work, probably have more flow, I was just presenting an alternative method. I left one of my 3/8 lines unconnected and started the motor, there was a lot of flow,,
 
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although i doubt you will have any problems having the intake as warm as your engines temp is great better than stock manifold heat
 
Chevrolet chevette had one under the carb too,electric.
When the heater would fail it would ice up the screen and car would only idle.

i recall the ford ones,no control valves. I dont see an issue with it running continously at engine operating temp. Air/fuel has a cooling effect as well.
 
I would connect it, try it, and run it. It can only get as hot as your cooling system will allow, which means temperature should be 'governed' by the thermostat and radiator pressure cap to about 110*C. I live in Australia, on older cars we do occasionally fit a 'heater tap' which is something similar to the item shown in Reply #9 by slantsix64, the purpose being for cars where the heater has water flowing (and heating) at all times, it can be isolated during summer to prevent unwanted escalating cabin temperatures (usually caused by leaking/cracked heater boxes!!!). That said, most of our 60's and 70's models with water-heated inlets flow water continually, with no temperature control. If after trying it, you really think you need 'on the move' control of the heating, look for a cable-operated heater/water control valve off an older model car.
 
I would connect it, try it, and run it. It can only get as hot as your cooling system will allow, which means temperature should be 'governed' by the thermostat and radiator pressure cap to about 110*C. I live in Australia, on older cars we do occasionally fit a 'heater tap' which is something similar to the item shown in Reply #9 by slantsix64, the purpose being for cars where the heater has water flowing (and heating) at all times, it can be isolated during summer to prevent unwanted escalating cabin temperatures (usually caused by leaking/cracked heater boxes!!!). That said, most of our 60's and 70's models with water-heated inlets flow water continually, with no temperature control. If after trying it, you really think you need 'on the move' control of the heating, look for a cable-operated heater/water control valve off an older model car.

I posted a while back that I was thinking about running my heater hoses , strapped to the runners under side to add a little heat , under my victor intake , which is pretty darn tall.
I got no opinions on it , and havent done it , since I dont drive the fish in really cold weather.
a guy I used to know , had an old jeep gladiator pick up , and rerouted his regulated down fuel line across the top of his radiator , and sealed it w/ factory dumb dumb/putty , he bought from the jeep dealer , it did improve his gas mileage , according to him , which wasnt great on that vehicle to start with. He also had a throttle cable that he would pull out on the hiway for a steady rpm at speed. He would lay down across the seat w/ his feet hanging out the opposite door window, propped up so he could still see , he got a lot of looks from everyone that noticed it .
He died in a wreck on the way moving back to his original home in Alabama , went to to sleep while driving , he was a very good friend !
 
Nash had a water tube in the intake
In the top of the manifold cast in the top of the block under the intake manifold (a flat plate ) in the flathead Statesman / Rambler You could get the plate with two Carter 1bbls
Really helped keep the fuel in suspension
we tried taking it out for the Mobilgas Economy run
didn't help
Go for it guys
 
I run a Clifford shorty 4v intake and headers on a slant 6. When I got the car I soon discovered living on the coast and temperatures dropped below 55* on a humid day drive-ability was bad, would not idle, and drank fuel like the tank had a hole in it caused by carburetor icing.

I used some 1/2" aluminum plate cut to size that would fit under the carburetor, and cut a square hole in it. ( it looks like a carburetor open spacer) The second plate was a cover, and pancaked to the first forming a chamber. Then drilled and taped for two barbed fitting to attach heater coolant lines in series with the heater core. Bolted it to the bottom of the intake it circulates hot coolant all the time, (195 T-stat installed) and have driven the car in sub zero and mid 90s* temperatures with no problem.
 
Hey wjajr, which intake are you using? Do you how you attached the heater to your intake? I have an Aussiespeed which doesn't have attachment bolt holes. Just curious how you approached the heater set up. Did you attach the to pieces together with epoxy or? thanks.
 
the manifold will cool down fast enough as soon as you crack the throttle,
the aim of this is to help vapourise the accelerator pump shot in all circumstances and that it will do...

general running i.e any air flow will reduce, in seconds, the temperature of the base of the manifold on a hot or cold day

it just gets warm when the throttle is closed i.e at all times just before you need to make best use of an accelerator pump shot.

remember the original manifold was clamped to the exhaust manifold which will have conducted heat from one to the other regardless of whether the exhaust gas flap was open or closed. and of course exhaust is way hotter than coolant.



Dave
 
I must live in a different universe. I have Vixen's manifold heat totally blocked off and driveability is great even in cold weather. I drive her year round even in sub 20 degree weather. Even though I live in middle Georgia, it does get cold here. Even in cold weather, she's up and idling in under a minute. That's also with the choke adjusted WIDE OPEN and not even wired up electrically. It's never been a problem. I find it funny that when people add the Dutra Duals or headers no one talks much about manifold heat. I find it's a complete and total non issue.
 
i'm sure its fine

race focused manifolds don't have a hot box because they are used mainly for wide throttle open operation in race situations
who cares if there is a problem just off idle on a humid day when stuck in traffic

its not necessarily ambient temperature that causes a problem
Dry and cold no problem car will run fine i'm sure
hot day car will be fine

pump shot tuned to work with the set up you have... which includes a manifold that could reach internal temperatures below freezing, if economy is a concern that pump shot could be smaller

Hot box is included on OEM set-up to cover off a combination of humidity and dew point that causes puddling and then ice to form inside the manifold that can happen in real cold weather or quite clement weather... but it doesn't happen everywhere because its due to the water content of the air and the depression caused under the carb after the movement of air through its venturi. i.e the existence of the heat cross over has less to do with it being cold or hot weather and more to do with Humidity or dampness and pressure (or vacuum)

wet air goes through a carb and the pressure of it is rasied and lowered as it passes through the venturi
in the manifold it predominately sees vacuum when the throttle is not wide open
raising pressure causes the water in the air to stay in
lowering pressure will allow it to fall out
real low pressure causes a refrigeration effect
for air to expand into this vacuum it sucks in heat
that can...not will...can, cause ice in the manifold regardless of how hot a day it is

but you can help avoid it with a manifold who's ambient temperature is moderated by something that will never get to freezing

keep in mind that the vast majority of Australians live in hot places or places that can get quite hot. you can go skiing in Oz if you want but most live on the coast and it gets quite hot.
but you can also have some fantastic extremes in the dampness/humidity and not necessarily on hot days


Aussiespeed have decided to make a hot box attachment for a big long manifold. you would expect them to be the last people to be wanting to heat up their inlet, if this was about ambient temperature of the air.

with these installed you still have a nice cold charge going into the motor because the heated inlet cools damn quick when you start to do something like move.

as usual this is how i understand it, i am just some geezer sitting at a desk, who should be fixing a website but is messing on here instead :) .... i may be wrong

Dave
 
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When I first did my turbo slant six, I had a 90 degree carb adapter for a 500 Holley 2 bbl on the inlet of the turbo. At idle (in the summer) The bottom of the adapter would get ice on it, and the idle would surge. I epoxied some copper tubing to the bottom of the adapter and connected to the heater hoses. No more ice, and a smooth idle.
 
i presume the summer in silver springs has the odd day of humidity. if it was icy on the outside it will have been colder on the inside

and your set up created, on some occasions, a considerable change in pressure from high to low
and your inlet acted like an aircon unit or fridge.
compression a restriction and then freedom for what was compressed, to expand

i.e expansion of previously compressed gas stole all the heat from its surroundings.
just this time it was your inlet not a bag of chicken dippers from costco that froze

conditions were just right

different season early evening, R in the month no problem.... but every now and again
 
That was back in the late 1970's, in New Jersey. At idle air/fuel flow, the fuel would absorb heat from the adapter and vaporize and cool the adapter below 32 degrees. At that point the fuel would "puddle" the engine would be running lean. After the adapter had cooled, and the fuel would no longer vaporize, the excess fuel would slug into the intake and the engine would go rich. Since the fuel was no longer vaporizing, the adapter would start to warm up, and the process would start over again. That was the cause of the surging idle.
PS: There was no change in pressure. This turbo set up was a draw thru system with the carb on the inlet of the turbo.
PPS: I stated that wrong, Yes there was a change of pressure at the carb throttle blades. But no different than a carb on a intake manifold with out a turbo.
 
The description I would get is, " My car starts fine cold in the morning, back outta the of driveway, it's okay, first stop-sign it kinda runs rough and dies, immediate restart, next stop may or may not stall, rest of the day runs fine."
Carb icing, - hi humidity days with lower temps, we get it often spring and autumn.
You can actually take the air-cleaner off, look down the carb, and actually watch "snow" form just below the venturi, and snow will grow all around the throttle bore until it gets to and plugs the idle port, - the engine will then die/stall.
If you were to not restart the engine immediately, ( 30 seconds) - let it sit so the carb base absorbs some heat, it'd run fine.
Ford introduced an electric heated carb base gasket a few years.
That's why all the "stove and ducting" from the ex manifold to the air cleaner on many models.
Same effect as removing the tire valve core to deflate tire, and "snow" builds around the valve stem where valve cap screws on.
It just takes a few seconds ( a couple of blocks of driving) for heat to warm the carb enuff to stop snow.
It's all about humidity .
Good luck, happy turkey day ! !
 
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I find it funny that when people add the Dutra Duals or headers no one talks much about manifold heat. I find it's a complete and total non issue.

When I installed Dutras on my '65 Dart, I also installed a water heated base plate from a Ford FE engine. Worked wonderfully. But then I lived in the Seattle area where the eternal mist starts in October and lasts to July and carburator icing is a real problem.

If a heated manifold was not needed, the factory would have elimated it as a cost savings and increase the profit margin on the engine line.
 
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