AN Fittings for Cooling System

[TFish2607]

I’m currently in the process of doing a complete overhaul and build of several systems in my car as I prepare to attend the Ponies in the Smokies (PITS) in 2025. As I look at some options for my car, I’d like to begin the process of completing a wire tuck and cleaning up some other systems in the engine bay.

With that said, one thought that came to mind was not using the old cooling system rubber hoses and switching to braided lines and AN Fittings. During my research I’ve not found anyone who has completed this before, but may have missed something as I scoured the internet.

I did locate an oil filter relocation kit from MMR that utilizes a -16 AN line water fitting. After locatinf this, I turned to measuring the current diameter water hoses and comparing to the size of the -16 AN fitting they use with their kit. During this I found a 38% reduction in size of the hose when switching to AN fittings.

My first question is, has anyone ever made a switch to AN lines?

Second is, any reason why they would use a -16 AN line and reduce the size of the hose? I’m sure Ford designed it to use a hose that big for proper cooling. I tend to think reducing it would cause the engine to suffer and possibly have cooling temp issues.

Any info or feedback on this would be awesome.

 

[07 Boss]

Any changes in flow and capacity will reduce the efficiency. You will be decreasing both. Why not just get the proper hoses instead?

 

[TFish2607]

Any changes in flow and capacity will reduce the efficiency. You will be decreasing both. Why not just get the proper hoses instead?

My initial thought was try and dress up the engine compartment and have a custom look while using some great hardware to do so.

It seems that this won’t work as good. I know many LS, SBF, SBC engines have thermostat housing with AN fittings and use this idea and that’s what brought this thought to mind as well.

 

[07 Boss]

My initial thought was try and dress up the engine compartment and have a custom look while using some great hardware to do so.

It seems that this won’t work as good. I know many LS, SBF, SBC engines have thermostat housing with AN fittings and use this idea and that’s what brought this thought to mind as well.

Well just go out and get the right size hoses and fittings. Many companies out there will manufacture them, just tell them the specs and what connectors you want on there.

 

[Autokyrios]

Might reach out to MMR and check that you have the right kit. I know they sell several different sizes and their website is kinda wonky (doesn't always pick up the drop-down info). I just happen to recall this bc I'm looking to pick up that kit, too, but got stalled because of the hose size selection and couldn't remember the size and haven't had time to crawl under the car to verify.

 

[Larryfishes53]

I used -8 AN for my transmission lines and I was expecting it to be harder than it really was. I’m running a custom Transmission cooler and the factory lines wouldn’t work as is.

 

[Autokyrios]

Stock GT lower cooling hose (running out by the oil filter) is 1.75in. If you swap oil filter plates to an aftermarket one (like the MMR unit) there's AN options. Big AN fittings can be pretty expensive, though. Upper might be a little harder as I believe it's block-specific. There's probably someone out there who makes an AN version, or you could have one fabricated if you know someone who can weld it up. If you just want the braided look, there's braided sleeve kits that have AN-looking aluminum covers. Done right they actually look decent.

As for the trans-cooler, running a hi-stall TC and a built trans, I have heat to spare. I was running a large plate-fin cooler but I'm in the process of moving it to the back of the car with a shroud and fan. There's a good amount of heat and I don't like having it bathing my radiator and condenser.
Long as you don't change the tubing diameter you're good. If your cooler isn't spec'd for the same flow as the line (like putting 8AN lines to a cooler made for 6AN) you'll have problems due to pressure increase. In the setup I've been running for a few years, I kept the hard-lines up until just behind the radiator, then cut off the stock ends and added AN fittings. Then ran braided line to my cooler. I have used the old transmission cooler as a steering cooler up until now (going electric).
Also, I can't stress enough how important a dedicated transmission temperature sensor/gauge is. The stock computer reading is for sh*t.

 

[ghunt81]

I'm pretty sure NASCAR runs -16 AN on their cooling systems, but those fittings are $$$. Also I would think you'd be looking at some custom parts to make that happen on a 4.6.

 

[EBABlacknChrome]

Read your post, then saw this on FB

 

[rocknrod]

Back in the early 90's Spectre Performance used to make fittings similar to those. They worked well, I had em on a big block. Now all they have are clamps and such they really went backwards.

 

[Autokyrios]

Trying to find installation stories and signs of life. Video seems to indicate sealant is used, which wouldn't make me feel great.