TheDieselStop.Com Forums: AIS Problems

Lone Wolf,

Thanks for the question. Incidentally guys if any of you have questions don't hold back, by all means ask them. No question is a dumb question, and all of your questions deserve answers. Participating in this forum and answering your questions is my favorite part of my job, so keep them coming.

Think of the restriction indicator, as sort of a circuit breaker like you would find in your home. If you were to add another appliance to a given circuit in your home that required more current, you may need to increase the size of the circuit breaker supporting that circuit. Now of course, you need to keep in mind that the circuit itself needs to be designed to carry the extra load of the new appliance.

The design and technology used in the new AIS give it airflow characteristics that allow it to support a tremendous amount of horsepower while giving you excellent dust efficiency (99.99%). These two characteristics are not normally found in the same system, as there is usually a trade off. The indicator circuit is designed to alert the operator when it has detected a 10" rise in restriction across the element due to the dust load. When calibrating for this 10" rise we need to determine a baseline, and that baseline is determined using a stock unmodified vehicle because we could not possibly calibrate for all of the various modified combinations out there.

Now if you add a modification such as a new performance exhaust system, and your new AIS's indicator is immediately triggered, that doesn't mean that the new AIS is more restrictive, it simply means that you are making more horsepower. You have gotten what the exhaust mfg. has promised you, more flow. All you have done is just changed the baseline of your restriction indicator's calibration, which is not a bad thing, you are just making more horsepower. As you install power adders, the calibration baseline of the restriction indicator changes due to the increased airflow. To retain the proper function of the indicator as you are adding modifications, you need to install a stiffer indicator that will work with the system. Now I have heard that others have installed the OEM indicator, as it is stiffer and have had good results with it on modified vehicles. I have not tried this so I am just going by what I have read here on the forum.

Now a bit here on warranty. I cannot tell you what modifications will and will not void your warranty, check with your dealer on that. Historically, intake and exhaust systems have been acceptable modifications that have not voided vehicle warranty. Recently I have heard that some vehicle manufacturers have began to deny warranty claims on vehicles where aftermarket induction system have been installed, based on their inability to filter out dust and dirt from the intake air due to low efficiency high flow media, and less than desirable gasket sealing.

Dust and dirt particles are not a good mix with turbo blades that are spinning at 100,000+ rpm.

My advice to you is to never in any case trade off dust filtering efficiency for increased air flow, instead look to increase both simultaneously in conjunction with cool air induction, rain / snow separation and easy drop in installation. The new AIS can offer you all of the above with a 99.99% dust efficiency rating.

Before you buy any intake system, always ask to see the dust efficiency rating of the system to ensure you are not making a trade off.

Thanks, and keep’em spoolin…

Jordan S. Flagstad
Senior Automotive Engineer
Donaldson Company
Minneapolis, MN