Volant CAI kit on a 2001 F250 V10

Disconnect the battery negative cable. Not only will it make it safer working on the vehicle, it will give the PCM a chance to reset and relearn after the upgrade.

Trace the MAF wiring from the bottom of the air box down to a connector on the fender well. It is just forward of the upper shock mount, and below the brake lines. The brass ‘T’ in the following picture is my oil pressure gauge remote connection.

The MAF-side of the connector is held to the fender-well by a plastic pin. Pull it straight and firmly away from the fender-well. Disconnect the connector by pushing down on the small tab. You might need to wiggle the connector a little bit to get it free before pushing the tab.

Next, undo the clamp that holds the stock air box together.

Now, disconnect the intake tube from the air box, and remove the MAF-side of the air box from the vehicle.

Remove the forward section of the stock air box by pulling up on the rearmost side. It is held in place with two pins that are inserted through rubber grommets in the bracket. Slide the forward ‘snout’ of the air box from the hole in the radiator support.

Next, remove the MAF from the rear section of the stock air box. Here is a picture of the MAF still inside the stock air box.

Separate the MAF insert from the rest of the air box by inserting a screwdriver into one of the slots and pry it out.

Disconnect the MAF wiring harness from the MAF sensor, and remove the wiring harness from the air box.

Here is a view of the MAF housing still bolted to the air box plate.

Remove the MAF from the plate. Two screws hold it on, they have 10mm heads.

The MAF itself:

At this stage, I removed the MAF sensor from the housing to clean it and keep it safe. This requires an anti-tamper Torx bit, the type with a hole in the end of the bit to match the pin in the screw. BE CAREFUL. When I cleaned the MAF a few years ago, I had the brass insert spin in the plastic and the screw would not come out. I had to squeeze the plastic with a pair of vice-grip needle-nose pliers and glued the insert back into the plastic with Crazy-Glue. If you do not want to remove the MAF sensor from the duct, it is not required, just be careful from this point forward.

Going back to the intake tube, remove the PCV breather and IAC hoses. They just pull off. Rotate them first to free them, then pull straight off.

Unscrew the clamp holding the tube to the throttle body and remove the intake tube from the vehicle.

Going back to the kit of parts, locate the MAF adapter that goes inside the air box, the foam gasket, and four bolts/washers/nuts. Remove the cover from the Volant air box.

At this point, the Volant instructions say the stock MAF has a gasket that you should reuse on the outside of the air box against the MAF housing. My 2001 did not come with a gasket. I used some black RTV, made a VERY thin coating on the MAF adapter, let it skin for 10 minutes, and assembled. I used the foam gasket on the outside of the air box because it made a perfect seal to the textured air box surface.

Be careful to align the MAF adapter, the air box, and the MAF housing so that there are no obstructions to air flow. I slightly chamfered the inside leading-edge radius of the MAF with a die grinder, but that was probably overkill. Check the alignment and make sure the air box, the MAF adapter, and the MAF itself line up correctly, otherwise you could create eddies in the air flow that can confuse the MAF sensor, as well as impede air flow. Probably not enough to ever notice, but I figure it couldn’t hurt.

Use two bolts to line up the gasket, MAF adapter and air box, and hold them all in place with one hand.

Line up the MAF with the two bolts, and temporarily hold in place with two nuts. Insert the other two bolts, install flat washers, lockwashers and nuts. Then remove the first two nuts, and reassemble with washers and lockwashers.

The Volant kit came with only 4 flat washers, so I added four more stainless washers on the inside to avoid cracking or distorting the MAF adapter. I also applied red Loc-Tite to the bolts even with the lockwashers.

Finally, tighten all four bolts slowly and evenly. The brass inserts in the holes of the MAF should allow a lot of torque to be applied to crush the foam gasket, but do NOT tighten down too far. How much is too far (or not enough) is up to you. You should be able to feel when the MAF adapter, air box, gasket, and MAF contact as you tighten down the nuts.

Next, we need to remove the stock air box bracket held on with three bolts. They are 10mm heads.

Then, remove the one bolt holding down one side of the evaporative emissions canister, but do not remove the canister bracket. Make sure the captured nuts are centered in the holes.

Install the Volant air box in the vehicle as pictured.

Using two bolts from the air box bracket, bolt down the Volant air box. The bolt holes should line up perfectly with the captured nuts.

Install the large rubber coupling from the kit onto the large end of the Volant intake tube.

Fit both of the large hose clamps over the coupling, but do NOT tighten yet.

Fit one of the small hose clamps on the small end of the Volant intake tube, and install the small rubber coupling, and again do NOT tighten the clamp yet. Push the coupling up onto the tube as far as you can, leaving a small amount of the coupling exposed past the end of the tube, as pictured. Slip the other small hose clamp over the MAF sensor.

Install the Volant intake tube onto the throttle body, pushing the large coupling up onto the throttle body as far as it can go, to where it stops against the flange. Tighten the first large hose clamp against the throttle body, leaving the second large hose clamp loose.

Align the small end of the air tube so the rubber coupling can be slid onto the MAF. Holding the large side of the intake tube, slide the small coupling onto the MAF housing until it stops against the tab visible in the following picture.

Wiggle the air tube around a bit by hand to make sure it’s not pushing to one side, and once it’s aligned properly, tighten all hose clamps.

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Slip the IAC and PCV hoses onto the nipples on the Volant air tube.

In the instructions, Volant states that some models have an air temperature sensor, most likely for the climate control, in the intake tube or air box, that needs to be relocated to the new air tube. My 2001 does not have that sensor, so I installed the plug that Volant provides. This could have been done before the air tube was installed in the vehicle.

I then removed the captured nut left exposed at the radiator support from the stock air box bracket.

I then connected the MAF harness to the MAF sensor before reinstalling it into the MAF housing. I coated the o-ring with some dielectric grease before installing it.

Reconnect the MAF harness to the chassis harness connector. Secure the harness with a tie wrap to a convenient location, and push the connector back onto the fender well.

Install the Volant air filter into the air box and tighten the hose clamp securely.

Reinstall the Volant air box cover with the four screws removed earlier.

The job is FINISHED! Clean up your tools, and remove everything else from the engine bay before reconnecting the battery and starting the engine.

Before and after pictures. Notice the smoother flow of the intake tube from air box to the throttle body, and the smaller initial size of the intake tube.

First impressions were of a slightly louder intake sound, but after driving it a bit, it can be a bit louder than stock, which is a good thing. No drone at highway speeds, or light throttle, and only a slight drone at the magic 1500-2000RPM medium-throttle spot where the V10 likes to make it’s uniqueness known.

Whenever the intake sound gets loud in the midrange, it seems torque, or at least throttle response, has increased. The Volant CAI seems to have improved torque at certain points in the RPM range where the original stock system fell a little flat.

High-RPM power has increased slightly by the seat-of-the-pants feel. I also have headers and modified Y-pipe, so that is sure to help gain more power from the intake upgrade.

Using an Autotap scanner, I monitored intake temperatures before and after, and they either stayed the same, or slightly improved. It certainly did not make it worse than the stock setup. Even the stock setup has holes in the bottom of the air box that draw in hot engine bay air.

MAF function has not changed, which I would not expect it to because the original MAF housing is reused.

Overall, I have to give this modification a definite thumbs-up in all respects. Ease of installation, mild power increase, nice sound, and great quality parts in the kit.