Cold air intake on a 360 v8

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edognight
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Cold air intake on a 360 v8

Post by edognight »

I was looking at one of those "dream jeep" websites, and it had a pic from the underhood of an 86 waggy and it had a tube from the front of the car upper left, facing the car from the front, to the intake/ait filter. Looks like it was designed to channel cool air from the front about the grille area. Was this a stock cold air intake? mine doesnt have one, but it would be a pretty cool project. I didn't know if there was an existing kit, or some such thing...
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tgreese
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Re: Cold air intake on a 360 v8

Post by tgreese »

Yes, factory equipment. What year is your Jeep?
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HowardT64
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Re: Cold air intake on a 360 v8

Post by HowardT64 »

I had thought of doing this as well. Does it make a difference?
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440sixpack
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Re: Cold air intake on a 360 v8

Post by 440sixpack »

Most manufacturer's started doing it in the 70's. Jeep as well.

Does it do any good ? sure. the colder the air the better for performance. but you're not going to notice the difference.
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Tatsadasayago
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Re: Cold air intake on a 360 v8

Post by Tatsadasayago »

The cold air system is strictly an emissions thing--so yeah it helps but you really won't notice any difference. Aside from that, it does help keep dust stirred up by the cooling fan or underhood smoke from being drawn into the air filter housing.
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Stuka
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Re: Cold air intake on a 360 v8

Post by Stuka »

The stock air cleaner housing is *SO* restrictive that you lose more power than you would gain by having cooler air. The only thing it can help with it potential vapor lock.

With my old Cherokee I picked up a very noticeable amount of power by just switching to a 14x3 air cleaner without the snorkel. And actually Engine Masters this week just had an episode comparing air cleaners. Show just how bad the factory single inlet air cleaners are.
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candymancan
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Re: Cold air intake on a 360 v8

Post by candymancan »

These types of air intakes are ram air intakes.. The air goes directly from the grill when driving to the engine. ZJs have this as well right by the headlight.

Stuka are you sure a round air filter on top of the engine without a ram tube by the battery gives you more power ?

I mean even sports cars have a tube to get cold air from the grill area or lower from the ground. My brothers camaro in the signature runs like BEEP on the track if it sucks in warm air. But i know a LS engine is diff from a amc 360 lol.

Also how do you get around not being able to use the emission junk thats all over the stock intake ? There are like 4 vacuume lines in various solenoids on it. Did you just plug them or what ? and where would you put the oil cap breather tube ?
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Re: Cold air intake on a 360 v8

Post by Stuka »

candymancan wrote:These types of air intakes are ram air intakes.. The air goes directly from the grill when driving to the engine. ZJs have this as well right by the headlight.

Stuka are you sure a round air filter on top of the engine without a ram tube by the battery gives you more power ?

I mean even sports cars have a tube to get cold air from the grill area or lower from the ground. My brothers camaro in the signature runs like BEEP on the track if it sucks in warm air. But i know a LS engine is diff from a amc 360 lol.

Also how do you get around not being able to use the emission junk thats all over the stock intake ? There are like 4 vacuume lines in various solenoids on it. Did you just plug them or what ? and where would you put the oil cap breather tube ?
The factory setup is not ram air. It does get air from outside the engine compartment, but thats it.

And yes, an open element 14" gives WAY more power because the factory air cleaner system is incredibly restrictive. Yes, if the under hood temps are very high, it can cause issues, which I mentioned above.

Newer vehicles use snorkels that probably flow 10x more air than what 60's and 70's vehicles came with. Even if the air is cooler, if you can't get enough of it, you will be limiting power. The intake on my '16 Mustang was like 4.5" in diameter (guestimating here), the one on each of my FSJ's is about 1.25".

Now if somebody went with a more modern intake system which was much larger and got air from outside the engine compartment,t his would be the best setup.

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Re: Cold air intake on a 360 v8

Post by 440sixpack »

Cowl induction, ram air, N96 they were all intended to give a little pressure and cold air . such as with the 1970 AMX the ram air was a joke because where the scoop was placed was in a dead spot as the air deflected of the front of the hood. but it did provide cold air.

The colder the air the better, it's simply physics to an internal combustion engine. the stock cold air set up is better than pulling hot air off the engine .

None of this matters on a 21 second Jeep.
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Re: Cold air intake on a 360 v8

Post by Stuka »

440sixpack wrote:Cowl induction, ram air, N96 they were all intended to give a little pressure and cold air . such as with the 1970 AMX the ram air was a joke because where the scoop was placed was in a dead spot as the air deflected of the front of the hood. but it did provide cold air.

The colder the air the better, it's simply physics to an internal combustion engine. the stock cold air set up is better than pulling hot air off the engine .

None of this matters on a 21 second Jeep.
As I said above, a GOOD cold air intake would be great. The stock Jeep one is not good by ANY means. It literally acts as a restrictor plate to get past emissions. It was DESIGNED to limit how much air the engine could get.

Just saying on both of my carb'ed jeeps, having an open element air cleaner provided a VERY noticeable bump in power over the stock air cleaner setup. Yes if its 100F+ out, the hot air can be an issue. Which is where a GOOD cold air intake would come in to play.
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Re: Cold air intake on a 360 v8

Post by candymancan »

Question for you guys. The stock air hat have those air dams inside just before the filter. I noticed the first air damn is closed when the engine is off and it lifts up when its on which opens the door for that warm air duct above the exhaust manifold to warm the engine up faster.

However once my engine is hot and been driven when i park it and check that valve or dam its still up.. Blocking all the air that would be coming from the air tube.. If i push it down by hanf it goes down but then pulls back up via the vacuum line on it. When i turn the engine off it goes back down.

So it isnt Stuck per say but it is staying up regardless of the engine being hot or cold. I put a camera there and thought maybe if i step on the gas its suppose to drop down ? but it didnt move.

When is this dam suppose to go down ? Im wondering if its alwsys up blocking the fresh air from getting to the engine and it jist always sucks in the hot exhahst manifold air
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Re: Cold air intake on a 360 v8

Post by Cecil14 »

You've got it hooked up to the wrong vacuum line. It should be on a CTO, cutting off vacuum once the engine is warm. Or better yet, disconnect it altogether, unless you REALLY need it for emissions.


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Re: Cold air intake on a 360 v8

Post by candymancan »

Dont need emissions so i thought about disconnecting both of those valve or dams or whatever abd plugged the ends with those rubber caps or a screw like you said. Plus im sure this thing being blocked is probably hurting my gas mileage and robbing me of power since the engine can only breathe through the small hole under it .

Just wanted to be sure. Say if i wanted to get an open air filter to clear up the engine bay a little bit. Where would i put the oil filler cap tube ? And the vacuum line thats under the air hat thing near the pcv
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Re: Cold air intake on a 360 v8

Post by KJ Ryu »

Take the tube off the oil cap, or get one without a nipple. Not sure which vac line you're referring to. Mine have always had most of the emissions stuff removed before I got them.
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Re: Cold air intake on a 360 v8

Post by candymancan »

There is a vacuum line which i believe is for the pcv filter.

Its connected to one of those little plastic coin sized things that a lot of vacuum lines have.

Ill have to take a picture then i guess. Isnt the hose on the oil cap on the filler tube suppose to help suck blow by gases. If i disconnect it wouldnt it cause pressure to build in the engine ? Just wondering becsuse ny air filter is a tad oily in the direction of that cap.hose so it seems like my engine is sucking up through that tube to the carb. How do i check if the pcv by the carb is working ?

Here is a pic of the vacuum line. isnt my pic. but if you look at the carb top right corner there iss disconnected little vacuume line with a yellow.white round thing attached to it. This line plugs into the stock air hat underneeth
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Re: Cold air intake on a 360 v8

Post by 440sixpack »

Colder air is always better. that's why before fuel injection we had to jet snowmobiles for temperature.

I'm not sure what advantage there would be to restricting the air intake of air to the engine for emissions .but if there was leaving the choke on would be cheaper and easier than a fresh air induction system.

I used to turn my air cleaner lid over for a big boost in power. but I never went any faster. funny how that works.
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Re: Cold air intake on a 360 v8

Post by tgreese »

For emissions, whatever design they put in place would have to work with the TAC (thermostatic air cleaner) functions. There are two air doors that are part of the TAC, one to admit hot air from the exhaust manifold stove to improve cold-start/cold-weather performance and prevent carburetor icing, and one to close the air cleaner when not running. Closing the air cleaner keeps the fuel fumes from the float bowl from escaping, and directs them to the vapor recovery canister.

I expect there is a trade-off between making a non-restrictive design and one that will carry out the TAC functions, and still be economical. AFAIK there is no emissions advantage to restricting air induction per se.
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Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
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Re: Cold air intake on a 360 v8

Post by Tatsadasayago »

I added a second inlet snout from an OEM air cleaner which made a very noticeable difference in power.
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Re: Cold air intake on a 360 v8

Post by Stuka »

tgreese wrote:AFAIK there is no emissions advantage to restricting air induction per se.
During the 70-80's the only way to get larger engines to pass emissions was to choke them down. Thats why 4v carbs were no longer available, cam profiles changed, etc. Restricting the amount of fuel and air that the engine got was pretty much a requirement. Thats why we had 155hp 5.9L V8's.
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Re: Cold air intake on a 360 v8

Post by FSJ Guy »

Tatsadasayago wrote:I added a second inlet snout from an OEM air cleaner which made a very noticeable difference in power.
And it looks pretty darned cool, too!! LOL!!

If you don't have the rear window washer, you can run the 2nd air hose right to the header panel, attaching it with a second factory mounting plastic part that is on the other side and it looks like a factory setup.
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