I recently bought a 99 F250, was wonderin whats a good cold air intake for the 7.3?

 

Well you could read all 170 something posts on the "Intake CFM Shootout" topic. Those were fun times.....

Most folks on these boards will pick either the AIS, AFE Stage II, or the Tymar (also can be the DIY intake with the Napa 6637 filter).

The AIS is a Ford OEM replacment box, and is an extreme duty filter that is far superior to the stock airbox that comes on the 7.3L. The filter element is the same type as what is used on the 6.0L trucks. It's a closed intake box, so you keep the factory look and sound.

The AFE Stage II is the most expensive one of the three, but it's a nice setup. Get the Proguard7 filter element, or the new dry filter. It's an open element intake with a shroud to separate it from the rest of the engine compartment. Does more good for noise reduction than anything else.

The Tymar filter is a huge paper filter that replaces the entire stock airbox assembly. If you order the Tymar brand, you get the filter, intake tube and all the accesories. The do it yourself is a copycat of the Tymar filter. For that all you need is to run to your local Napa and pick up the filter part #6637, a small piece of 4" exhaust pipe, and a 4" hose clamp. Remove the stock airbox assembly and use the exhaust pipe to couple the filter with the intake tube. It's the cheapest route to take of the three big intakes.

There are other intake choices out there, so feel free to shop around. From personal experience I will tell you that I'll never put a K&N on my truck. I had the drop in filter from K&N that fit in the stock airbox, and that was a dirt leaking POS.

 

I am also at this stage and looking at intakes.I havent narrowed it down yet and would love to also hear of the pros and cons.

 

morris86 and laj10, Welcome to FTE.


Guys I would start with the cheapest way to go. And most of us go there. The 6637. The DIY monster filter, then you can learn more here and decide if you want to go with a more expensive setup. Read as much as you can here.

Good luck, and have lots of fun.

 

darn, double take again

 

Pros and cons:

AIS - Moderatly priced, excellent filtering, factory look, filters can hold a ton of dirt before requiring replacment, it's more restrictive than some of the others so it becomes an issue in higher HP applications.

AFE - Expensive, looks great, just a little bit noisy compared to the stock closed airbox, filters are washable and reusable so you don't have to keep buying replacments, standard media (blue filter) is not the best at keeping all the dirt out, you have to upgrade to the ProGuard or the dry media for better filtering and protection.

Tymar (or DIY) - super cheap compared to other intakes, it's completely open so it's very noisy. Paper elements are huge so they can go a good while before needing to be replaced, greater chance of user/installer error if you go the DIY route, flows a surprisingly large amount of air for a paper filter.

 

Can the AIS flow enough air when you throw a chip and exhaust in the truck?

Rick, the site has really been acting up for me lately, I dont think it is just you.

 

I was lookin at the afe stage II, but when you say its a little noisy you mean the turbo's louder or somthin else.

 

If you do the fender sleeve mod to the AIS box, then yes it will flow enough to keep up with a chip. If not, you can pull that filterminder all the way down.

You'll hear a bit more engine and turbo noise. I've run both the 6637 filter and the AFE Stage II, and the 6637 is much noiser. The AFE isn't loud enough to be annoying (at least in my opinion).

 

Pocket
You mentioned that the AFE was washable/reusable. Seems like I remember a prevoius discussion where folks were slaming washable filters in general on the basis that they could never get them as clean as they would like Do you have an opinion on this?

Also, I plan on doing an AIS mod to my truck. The current stock configuration already comes from the fender area. Does the AIS require a bigger fender hole or something?

 

Happened a couple times yesterday to a few of us. Guess a nich they will work on.

 

The whole discussion on washable oil based filters came from here: http://www.duramax-diesel.com/spicer/index.htm

The K&N has been found to filter less dirt than many others. Some folks running the K&N have had issues with dust being found in the intake tube, and/or silicone levels high in an oil analysis. Not everyone has had trouble, but there have been a few. The drop in K&N that I ran for a very short time on my truck did not seat properly with the stock airbox and allowed a lot of unfiltered air in. That's why I don't advocate K&N for the PSD's.

The AFE filters are a bit different than the K&N version, especially the ProGuard. Those filter much better, and leave you with a clean intake and low silicone levels in your oil. Look at a ProGuard filter compared to a K&N. You can see small pinholes clearly right through the K&N, not with the ProGuard.

As for washing the filters. It's easy, just follow the instructions and never ever use high water pressure to clean them out.

 

Go the 6637 route unless you have the money for a Stage 2, and avoid K&N at all costs unless you like replacing your turbo.

Ya, my K&N never fit right either it actually broke one of the tabs on stock air box, so after that I ditched and went for the 6637.

But if you want a K&N filter I'll sell it to you real cheap, only 5,000 miles on it.
I would kind of like to sell it, but I would feel bad if some unknowing super duty experienced the wrath of K&N.

 

If I go with the 6637 should I or could I make some sort of "heat shield" between the motor and the filter?Also is there any worry about the filter getting wet since it is not partially enclosed?

 

I had the 6637 installed for about a year & decided to spend the $$ for the AIS. I love knowing that my engine is getting good filtration & I don't have to listen to the annoying vacuum cleaner sound anymore on hills. I don't have the fender sleeve & can pull the filter minder a little with no chip. Need to do the fender sleeve, but otherwise, love the AIS.