Inliners International Forums General Discussion Engines heated intake

Question, is it still a good idea to have a heated intake if you live down in central texas where it doesn't really get all that cool very often?? I have 235 with offy intake & fenton headers running 2 single carbs. thanks for the info, just trying to get all i can out of my ride.

wendall

YES...you do need a heated intake. The problem comes from the air/fuel going through the venturi at hi-velocity and then expanding in the intake and cooling. Our inline manifolds are "hung out" on the side of the engine and don't get hot enough to stop the cooled air/fuel mixture from seperating. Your 235 will run without a heated intake, but will run much better with a heated intake.

thanks for the info. I have been running with out it, but will soon change.

I disagree .I have a water heated intake,but when i shut it off the car runs just as well.I also get better MPG than i do with with the water turned on. Check your intake with a thermal gun and you will see what i mean. If your motor is tuned right ,and you have the air fuel mixture set correctly you will not want nor need a water heated manifold.Others may desagree,but some of that is because they sell it or have it on allready.Heck i thought i had the best thing till afriend shut it off and showed me.

i am sorry if I screwed up on posting I am new. What I am thinking is that the intake must get all the heat it needs from the fenton headers, to do the offy manifold on a 235 you have to grind it to fit the fenton headers and end up really close to them. With water heat the engine must have to heat up first to be effective and then your at 160 degrees The headers are alot hotter and heat up sooner.I have not run this combination yet but do have it set up on a rebuilt 235 setting on a 49 chev 1/2 ton frame and i am very intersted in hearing comments from anyone who has been there and done it.

Heating with the exhaust is the best I have found. They heat together & stay about the same temp when running. The top of the intake is cooler as heat rises but inside the
fuel mixture will faporize better when hot than cold.

When headers are used this all goes away & water heat is not enough, especially in the colder climates. The 6cyl. Vette. heated the same as the 'stock' single carb engines.
When cold you had to choke all three carbs to fire it up.

There was an adapter that used steel pipes
or hoses that went from the headers to the lower portion of the intake etc. It wasn't popular as they leaked & 'stunk' up the car.
Twin carb set ups were always hard to keep in adjustment too. Eventually most went to 3 pot set ups with headers and the heat tubes dissapered as gas was 30 cents a gallon and
no one cared about economy at that (1950s)
time.

If you are in Texas & the weather is warm wait till it gets hot before you "jump on it"
(the engine that is). Forget the water hoses
that they can break & leave you stranded and
don't help except in BAD weather.

Good luck, JM #3370


------------------

Heating the intake has proved very helpful in several past setups for me, engine seems smoother and more responsive. Cleared up some flat spot/hesitation in a couple of multi-carb setups and a single 4-barrel as well. Cold starting is not an issue here in FL, but keeping the mixture vaporized in an alloy intake is where the heat really helps.
"Your results may differ!"

thanks for all the replys, you are right about the fenton headers being close to the intake, I am not really sure you could put a heating plate on the offy without some more grinding. I am in the process of matching up same size jets & power valves with the folks at stovebolt engine, and will get it all back together to see how it runs before going back the heated intake idea. thanks again, wendall

Hey guys, let me jump on in here & ask for some advice also. I'm in the process of installing an Eddy Edmunds dual alum intake which is of the hot water type. The ex man is split, thus duals. Should I run coolant or block off the ports in the int man ? What about carb spacers ? Vinny G. # 3282

I'd try it without heat first, Vinnie. If you have hesitation at part throttle and flat spots in acceleration, see if hooking up the heat helps. If you have sooty exhaust but plugs look OK, you aren't burning the mixture well. Mixture cools from venturi effect of carbs - heated intake keeps it from puddling up into liquid again. Trial and error is about the only way to sort it out, every engine is different. Same with the carb spacers, the mixture has further to drop, so it may cool off too much. Underhood temps, thermostat and engine operating temp play a role too - and, a flathead breathes altogether different than an OHV. But think about it - Edmunds must've had a reason for putting that water jacket on his intakes.

Let me jump in here with a question...

I have a Clifford intake (with the coolant jacket) bolted up to my 250/6 with a 3190 Holley. I did not plumb any coolant lines in the original installation because I wanted a clean look.

Now in the cooler weather (even in SoCal) this appears to be a mistake, she sputters and coughs for 10 minutes until warmed up.

So I'm looking for a clean way to route coolant to the manifold. With the hoses on the other side of the motor, I was hoping someone has thought this out already.

Any advice, tips, and photos would really be appreciated!

Pete t

Pete

On the older motors there are pipe fittings on both sides of the thermostat housing. Others have a flat area that can be drilled and tapped for pipe fittings.This will supply hot water to the intake; run the outlet hose from the manifold, behind the valve cover to a "T" fitting in the heater hose circuit. This is about as clean as you can get. I've seen them run under the engine too.

I've got the exact problem that Jack described: Plugs look good, exhaust is sooty. How can I fix this?

My setup is: Original 235 in '54 Bel-Air, Bored .030", Head shaved .030" Clifford 260 mechanical cam, Clifford Water heat intake (water heat hooked up) Holley 4160 390CFM with 55 primary jets and 6.5" power valve. Fenton headers, 2" pipes w/glasspacks. Stovebolt "mini" HEI with mallory coil, 8MM plug wires. Autolite 86 plugs gapped to .045". 160 degree thermostat.

Car runs well, but I want to get rid of the soot. Help!

thanks,
robertG

[This message has been edited by Chiphead (edited 01-29-2001).]

I have the Clifford water heat intake, clifford shorty headers, Holley 390 carb, Clifford 264H cam on my 250 that also has 1.94" intake valves.

Ran it for a long time without hooking up the water heat and what I found was that even after the engine was warmed up, lots of low-speed stop&go driving or long waits at stoplights would cause the engine to load up and it would sputter or puff some black smoke once you got it going again. If I jetted it lean enough to keep this from happening, then it slowed down at the track (too lean).

After hooking up the water heat and installing a 195 degree thermostat, all such problems went away and I didn't lose any ET or MPH at the track either.

I routed the hoses similar to what Jack outlined. Got an older-style thermostat housing that had pipe fittings in both sides of it. Blocked off the one on the pass. side and ran the hose from the driver's side of the housing to the hole at the front of the intake. Then ran the hose from the rear of the intake into the heater core. The other hose from the heater core runs to the normal intake position on the engine. Heater works fine this way too and the hoses fit fine without cluttering up the engine compartment too badly.

Cheers!
-Will

I'm wondering if anybody ever ran these lines in stainless and what they looked like.

I have a 251 CI Desoto flat 6. This engine has a 260 duration at .410” lift cam, Chevy pistons and Chevy SS valves, dual Carter B&B carburetors, and a split factory exhaust manifold. This exhaust manifold is a true split as the heat riser baffle plate has been welded internally. As the intake and exhaust manifold are bolted together I have a good supply of exhaust heat to the intake at all times. The engine is running in the attached picture. I ran it about 10 hours on the test stand before installing it in my car with no problems.
Don Coatney

Supersix,

Any pics of your installation?

I did on my Chevy 216; it makes a nice, neat installation. I'll try and get some pictures to post. And I'm not the best tubing bender around - it took me a while!!!

Working class,

I am also in Central Texas and have never seen my stock baffle open. I was wondering who bent your pipes. I am in the process of adding Fentons or splitting a stock manifold and wondering the best way around the linkage or Motor mounts.

JC

The top part of a GMC inline thermostat housing has a pipethread cast into the part on the left side of the housing. This is the perfect place to run a hose or tubing from to the front opening on the manifold. If you use hosing, try to get into someone's catalogue and find shaped hosing so the bend is made into the hose. It will look much better and look pro. Also, only a minimum amount of hose will be needed. On the rear opening of the manifold, the outlet side, instead of going all the way to the heater, install a "T" at the temperature guage probe and, once again use the pre-shaped hose. The hose will look good, but for safety and a less likely chance of a leak developing, the tubing is better, stainless or aluminum.

Here is a thread that was started in January 2001. When searching this subject with our Search feature both standard and advanced nothing beyond 2016 come up and that is mostly not related to the search subject. The limit for searches is set at 10 years but it won't do that. The information is there.

I have an old clifford 4 bbl intake on my 235 I took out of my 53 Chevy 3100. I bought it in about 1981 when they were Clifford Research. It has a plate on the bottom of the manifold that has 2 copper lines that go to 2 different header pipes and fittings that you drill a hole in the header and weld on. Then it has a spacer plate about 1" thick that goes between the manifold and the carb that runs hot water through it to warm the carb.

Interesting. Both water and exhaust heat. Is this common?

Do you have pictures that you could post. that is interesting. My 270 GMC is a Clifford 4 bbl with Fenton headers and exhaust heat as you described. The 153 I'm building has an Offenhauser that was originally exhaust heat that I converted to water. Actual it could still be exhaust heated.

Yes it's laying in my shop. I will have to figure out how to post pictures on this site. It was in Cliffords early days out in So-cal.

Sorry I can't seem to figure out how to post pics. I go to full reply and see no file manager. Tried the contact us and nothing happened. Computers are not my best friends. I will keep trying.

Send them to me and I'll post them to my site and e-mail you a link.
jdiamond@optonline.net

To post here your photos have to be with an online host like Photo Bucket. On the H.A.M.B. you can post from your desktop and then post a link here. H.A.M.B.

Thank you panic. They should be in your email.

Clifford's original and early style manifolds did not have provisions for exhaust or water heat. I have an early 230-292 2 x 4 no provisions. What they did sell was a carb base plate that they called "thermo" something or other. I will have to dig out one of my old catalogs. Ran hot water through the spacer to provide heat, something akin to how Edmunds did it with their manifolds (copper tube cast into the manifold for hot water in and out. Clifford did it via spacer). Some later original era manifolds may have had a small chamber under the manifold cast in, no holes drilled or tapped, you made a plate.

Clifford changed its castings at some recent point (and may have done so with input by Tom Langdon). So my new style Clifford 235/261 2 X 2 has a hot water chamber built into the casting so no need to use the spacer plates. There is no provision on that manifold for a plate for exhaust heat. Other new style Clifford manifolds for other motors may have both, I have no knowledge of that myself.

Other manifolds of the era were cast so that they could be bolted to the stock exhaust manifold. Fenton, Weiand, Offy are examples. Others did not have any provisions. for those with the exhaust heat chamber, you could make a plate up and bolt it to the bottom of the manifold to cover the exhaust chamber and run copper lines from the exhaust manifolds if they had a provision for that, or run hot water. On my Weiand set up, I ran hot water. It always eventually had a small leak but it worked way better then the exhaust tubes.

One caution here, a lot of the vintage manifolds had a large core hole or two on the bottom, presumably to get the sand out after the casting, like one or two holes about an inch wide or so. After the sand was vibrated out, steel core plugs were staked in place. A good example is the offy intakes. These core plugs worked fine to keep exhaust gas in the chamber, but are prone to leaking when water is plumbed into the chamber so you have to weld aluminum plugs over them to keep it from leaking. So if you have a manifold like this, and are welding the core plugs shut, you might just weld a plate for the exhaust chamber (for the stock exhaust manifold) an eliminate the potential for a leak at that spot (which I always had, a little leak, constantly taking it apart and new gasket and silicone sealer).

I have one. I also have the carb spacer block with hot water. The manifold came drilled tapped and with the plate to run exhaust into both sides of it with the fittings. It also came with 2 threaded fittings that were welded over drilled holes in 2 specific header pipes so it would flow. As soon as I can figure out how to post the pictures I will. Panic is trying to help me post them but I'm still working on it.

Good day all, I also have a question regarding intake heat. I have a Fenton dual intake as well as Fenton headers for my 261. Both of the Fenton headers have a threaded port for exhaust tubes, but the exhaust heat plate I have only has 1 tube to connect to the exhaust. Searching the internet for other styles of exhaust heat plates finds the same sort of setup, only 1 tube to connect to the exhaust. Does connecting only 1 tube to the exhaust provide sufficient heat or should I be modifying the heat plate I have to accept an additional tube then connect to both of the headers?

When I ordered my intake from Clifford They were evidently in some transition process. The 4bbl intake I received has no name and the heat plate I bought to go on it did not fit. I returned it. They welded the plate on and sent it back. The plate has two fittings. I have it hooked to Fenton headers it could be used with water as well. It has been there for nearly 20 years.
I'm attaching a link to Langdon's that shows plates with two fittings that will bolt to a stock intake or the aluminum intakes designed to bolt to stock exhaust. The fitting on these are for water but can be changed. If yours can be fitted with another fitting to allow the exhaust to pass through it can be easily connected to your headers.
LINK

I have been running 3 - 45 DCOE Webers for quite some time. I don't think I have been having trouble. Of course, the runners are short and direct. Any comments or suggestions?

Will Willis

http://victorylibrary.com/graphics/mick53/20180218_181256.jpg

etc.

Thank you Panic. I've been out of town. You saved me a trip to my local library. I will still try to figure this out.

Any time.
If you right-click any image and select "view image" the description you need to enter in the "Enter the complete URL for the image you wish to display." box appears in the URL header.