i've been seeing a few people with an
"AF1 3.5" CAI with no insert (tune required)"

what is this about ...
i can not find any info on this

thanks

Ken

 

I'm really not sure what you are saying, but I will tell you what I know. The 3 1/2 comes with an insert that reduces the tube to a 3". You run the 3" if you do not have a custom tune that will enable the engine to handle that volume of air.

 

that could be it

thanks for the info

i was thinking of getting a AF1

 

x2 on what Bluejay said. I got the 3" because it didn't need the custom tune. If you run a 3.5" it needs the tune to prevent it from running lean.

 

This is from what I've understood when looking at purchasing one...feel free to correct me at your discretion...

The AF1 3.5" and 3" are identical, except the 3" has the insert that makes it a 3" ID/3.5" OD CAI. The 3.5" is simply a 3.5" ID CAI without any insert, so it's quite a bit larger and will allow a lot more airflow to the engine, which results in a very lean situation and the PCM cannont fully adjust the A/F ratio accordingly. So you need to have a custom tune to adjust for the lean condition.

Refer to modbargains.com for more information about the AF1 intake sizes http://www.modbargains.com/product.a...F-150_04-08_MW.

Or there's plenty of users on here, so search for their posts and they'll gladly help you out with any questions.

 

Guys, are you certain that the 3" AF1 doesn't need a proper tune to correct any leaning issues? I know that the S&B intake appears to run great with no issues, but when put on the dyno it's very apparent that it's running lean (which will eventually do some damage).

I wasn't sure about it when first posting, but after thinking about it I think it still does. I know for sure that the 3.5" does need a custom tune no matter what, but the 3" might still need it.....but you can get away without one for awhile without hurting your internals too bad.

 

A couple of years ago, Troyer did some testing and said the 3" would be ok. Personally, I would not risk it myself, but since Troyer posted that, it has been accepted as gospel. I certainly would not risk it on a 2004 or early 2005.

 

I wouldn't either ... I don't understand these people. The 3Vs are a completely different beast. I believe the S&B CAI is a 3" tube and guess what !? I was running extremely lean with the Edge and factory tuning. Let's see ... Do I spend $400 for custom tunes or risk blowing up the motor in my $30,000+ truck. It's not a hard decision for me.