Some more tech info from the guys at Fordchip...
Jerry made a post on Modular Depot about this.... I figure its worth repeating here as well especially after seeing the issues on my car.
Most blower kits relocate the MAF and filter to inside the fenderwell. Most of the time this works OK but can be the cause of some driveability issues. We have seem some cars that had a decel stall problem or a fluctuating idle when you depress the clutch and coast while coming to a stop. My car had the issue. After looking at several cars with the same issue we figured out that its actually caused by an erratic signal at the MAF and filter caused by air passing through the filter at speed. The issue is worse in a car with no foglights since you will allow more directly at the filter and MAF vs a car with a foglight filling the hole. This could also cause cruise "bucking" and other wierd probs while driving.
To test the solution I simply put a piece of cardboard into the fascia to act as a shield for the MAF and filter. The idle is perfect now and no more stalling. We have seen the same improvement in other cars that had the initial prob.
This should not be an issue with cars that have CAIs since the air will most likely stabilize before getting to the MAF. I could see a similar issue with Ram-Air set-ups though.
Turbulent air through a filter mounted right ot the MAF is never a good idea. So plan on using some sort of shield around any filter mounted in an exposed position.
Jerry made a post on Modular Depot about this.... I figure its worth repeating here as well especially after seeing the issues on my car.
Most blower kits relocate the MAF and filter to inside the fenderwell. Most of the time this works OK but can be the cause of some driveability issues. We have seem some cars that had a decel stall problem or a fluctuating idle when you depress the clutch and coast while coming to a stop. My car had the issue. After looking at several cars with the same issue we figured out that its actually caused by an erratic signal at the MAF and filter caused by air passing through the filter at speed. The issue is worse in a car with no foglights since you will allow more directly at the filter and MAF vs a car with a foglight filling the hole. This could also cause cruise "bucking" and other wierd probs while driving.
To test the solution I simply put a piece of cardboard into the fascia to act as a shield for the MAF and filter. The idle is perfect now and no more stalling. We have seen the same improvement in other cars that had the initial prob.
This should not be an issue with cars that have CAIs since the air will most likely stabilize before getting to the MAF. I could see a similar issue with Ram-Air set-ups though.
Turbulent air through a filter mounted right ot the MAF is never a good idea. So plan on using some sort of shield around any filter mounted in an exposed position.
