Most aftermarket intakes don't have provision for intake heat. Most abandon it on the assumption that if you are putting a fancy intake on your slant you are going racing, not trying to daily drive it, and will either (a) use headers or (b) not want your intake heated.

Clifford has sold a water box that can bolt to the bottom of some of their intakes that uses engine coolant to heat the intake. Other people have fabricated their own. But using engine coolant to heat the intake is much less efficient than using the exhaust. Exhaust is hot as soon as the fuel burns and is much hotter than the engine coolant. This heats the intkae up much faster than does a coolant heater box.

The real solution to improved exhaust flow and heating the intake is to run a Dutra front intake manifold and modify the rear half of the stock exhaust manifold.

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Casually looking for a Clifford hyperpak intake for cheap.

Ive been in a harbor freight a few times and looked around but I don't think I have bought anything there since I bought my kid a cheap RC plane (that never worked from day1 right out of the box) back when he was ~10 or 12 or so.. he's 27 now. I do all I can to avoid "made in China"
And yes it is unfortunate that it can't be avoided completely, in this day and age. I definitely do avoid their crap, whenever possible. You get what you pay for.

My rule concerning harbor freight is that it is acceptable only if the tool you want was capable of being built in the middle ages. Even then an antique 13th century hammer is likely of better quality even after all these centuries.

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https://www.flickr.com/photos/162600228@N03/

Hey, thanks!
The Offenhauser intake has a hot spot to match the stock exhaust manifold so it makes a good street manifold. The late Clifford intake has water heat as does the Chrysler marine intake. Once upon a time I had Clifford headers with small tubes that ran to the manifold hot spot. Most folks with headers though suffer without intake heat.
The port shape is the least of the problems.

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Joshua

The sad truth about Snap-On nowadays: 'Made in the USA with global components'. Translation: Parts manufactured in China, shipped to Wisconsin, and assembled by $15/hr workers.

Dan, I applaud your tenacity. But if you think that any sort of boycott is going to bring manufacturing back to the USA, I believe you're mistaken. Practically all "US made" goods incorporate components that are manufactured overseas. Its simple economics, no one in the US is willing to work for the wages paid in Mexico and China, and nearly no one is ready to pay twice as much or more for their endless stream of consumable goods (face it, practically nothing is durable anymore) in order to employ US workers at a living wage. Unless one or both happen, all of the sudden, the US manufacturing engine of the 20th century isn't coming back. As soon as the logistical infrastructure was built that allowed the continual, massive transport of goods built by cheap labor overseas, that genie was outta the bottle for good. Slap all of the tariffs on Chinese products you want, they'll do the same, and they can play that game a lot longer than we can. Some of us are old enough to remember how the Japanese fought this same battle in the 1970s. We see how that turned out.

Volaredon, Concerning the quality of Harbor Freight tools, yeah, it varies. I've got a Snap-on tool chest with lots of expensive Snap-on and Mac tools, and a a fair number of randoms. If the tools works well for the job and feels good in my hand, it's a keeper, I don't care where it's made. I've modified tools with a torch and grinder on many occasions to fit the job at hand. I'd sure rather do that with a random, than a Snap-on. Most of the tools I buy at Harbor Freight, which happens to be conveniently located a few blocks from my home, are often the one-time, or infrequent use variety, not hand tools. My pipe threader, for example, cost well under a $100 (I don't remember how much), and worked great the one time I used it to run gas line in my house. Now it collects dust, but it was cheap compared to a half a dozen trips to Lowes to wait around each time on someone to finally show up and tell me the pipe threader guy was on lunch. Similarly, I've got a few dozen screw clamps of various sizes. I use a few frequently, and all of them, once in a blue moon to build a table or some cabinetry. I'd love to have a row of Jorgensens to display on my shop wall, but I've got better places to spend the $1000 I saved.

There's my take on Harbor Freight, but as always, different strokes for different folks.

My feeling is that the preheat isn't gonna be that difficult to engineer. I haven't crunched the amp hours/heat mass increase numbers to know for certain, but my gut tells me that the heat tape wrap will work just fine during the short period that it's actually needed. More specifically, it only needs to raise the intake temp past the point of condensation for as long as is required before heat from the cylinder head itself takes over the job, or the choke is sufficient. That's probably in the neighborhood of five minutes or less most of the time, in Portland at least. In the winter, I could always plug in a block heater, if I ever actually drive the van in the winter.

Obviously there's a bi-metallic spring on that stock preheat set-up for a reason. You're much better off to avoid any preheat, once the engine is at operating temp, when a denser, colder intake charge lowers the threshold for detonation. So, in that respect, generally any engine is much better off without the hotplate 95% of the time. I assume that's clear to everyone, but it has seemed like the preheat is being regarded as a "must have to run, period" sort of thing. Clearly, it's not, it's a cold run device, to supplement the choke, that's all.

Here's a few pics of the Jeep header vs. the slant header and the head flange on eBay. Total cost about $110. Yeah, I could be dreaming, but it sure looks like (1) cutting off the jeep flange, (2) dividing the header into two pieces at the primary/secondary collector joint, and (3) welding on some pipe to lengthen and the get the spacing correct up to the head flange is going to get you darn close to the slant header configuration. Then it's just a matter of welding both pieces to their respective slant head flange and finally welding on a couple collector extensions and flanges.

At worst, there might be some creative headpipe bending required to clear the starter, but any decent exhaust shop can handle that.

Some of the Harbor Freight tools are from Pittsburgh.........

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Yeah, it's written right on them. lol

SK is the only brand of mechanic's hand tools still made entirely in the U.S. And they're great tools, just hard to find.

This is a complete misunderstanding of the matter.
Another misunderstanding. Be more careful of absolute words like "any", and pay some observant attention to how the valve actually works—it's not the way you appear to think it works.
Here we see where your misunderstanding comes from: you think you have a grasp on one little factlet—you're not correct, but you think you are—and then you just sort of decide/declare that you therefore understand the entire matter. Which you don't.
LOLfalse.
Uh…thanks for checking, Professor.
Can you show us anywhere that's been claimed?
Nope! You're flatly wrong about that. I don't feel like doing your homework for you, but the info's readily available here and elsewhere. Here's a hint: there's a phenomenon constantly working to cool the intake manifold while the engine's running, even when it's at operating temperature.

It's roughly 50/50 amusing and annoying how you come on here as a newcomer both to the board and to the Slant-6 engine and simultaneously act like you know nothing and everything. I don't think you're going to find much of a patient response.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

this short video may help the OP understand why a 'hot spot' is placed under a carburetor.

https://www.youtube.com/watch?v=JZ9BiaU7qkI&t=13s

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Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8

No, it isn't. Not on a carbureted engine. This has been known since at least the 1930s. Read this thread HERE and watch the video links. Unless you are running fuel injection or a dedicated race car, you need a heated intake manifold.

A cold air intkae is a very good idea to lower the temperature of the incoming air charge. By the early 80s Dodge was putting cold air intakes stock on the B series vans. Closed air cleaner plus a stock cold air system is the best factory setup you can get.

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Casually looking for a Clifford hyperpak intake for cheap.

Building headers in my mind is like building a house. It is almost always easier to build it from the ground up, than to gut an existing house and rebuild it. There are lots of man hours in doing either!

I have run carbureted engines with headers in the Northeast cold for a good many years. My truck always starts easily and runs fine once warmed up. That warm up takes probably 5 minutes or so driving down the road or setting in the driveway. Some people are so used to a fuel injected newer car that can be fired up and ran down the road immediately, that anything less than that is awful. Sometimes awful is in the eyes of the beholder too.

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Dude, I have no issue if You want to swap a 4.0L HO Jeep mill in, but what's with all this Hybridizing BS? You look to be making Your life 10x as difficult as it needs to be. And GM used carb-base heater grid units in the wonderful X-body 2.8L v-6's back in the good ole carb'd FWD days. Those cars ran great, but that system didn't always work great, and had terrible mid-warm-up driveability issues. It seems You're looking for reasons to put square pegs in round holes just to do it, if Ya' got nothin' better to do, good luck. The ??? is not can it be done, it's should it be done & why?

I'm not in the USA, and I avoid Hazard Fraught because I value my life, limbs, and digits; I'd also prefer not to damage my car, bicycle, house, and other stuff I use tools on, and I find a good used tool is often a better value than a bad new one.
And I believe you've decided what I'm doing and why (and where I live) based on assumptions and guesses with no basis in reality, and then gone ahead and held forth with a big ol' lecture about how wrong I am. Rude!

For better results, next time try ready, then aim, then fire.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.