Everybody loves a rematch. Well, it's time for the long awaited Air Box Replacement, Part Two. If you recall from our last episode, our heroic reviewer was vastly disappointed with the MTI Performance Air Box. It wasn't designed or built very well and wasn't worth the money. After messing around with my homemade system for a while, I started to look again at commercial alternatives. About this time, I was contacted by the nice folks at C/R Motorsports, the makers of the Pro Flow+. They offered to send me a unit free of charge if I installed and reviewed it. This seemed pretty reasonable to me, so here we are!
The Pro Flow+ came with everything needed in one big box. The ABS shroud is OEM quality with a textured finish and smooth rounded edges. The instructions are excellent and even include a template for cutting your radiator shroud. The kit also includes a K&N filter, recharge kit and all the clamps and screws needed. Unlike the MTI system, the filter on the Pro Flow+ clamps right to the MAF so no leakage of unfiltered air into the engine is possible.
The first step is to remove the stock air box and all it's mounting hardware. Then, remove the intake tract from the throttle body forward. Remove the MAF from the stock airbox and fit the K&N filter over the end. Put the clamp on but leave it a little loose for final adjustment. Reinstall the intake tract to the throttle body and lightly tighten the clamp to hold it in place. Now adjust the K&N filter so it's parallel with the radiator shroud. One everything is aligned you can go ahead and tighten the clamp on the K&N (make it tight). Next, take a pencil or Sharpie time marker and draw a line along the top of the filter on either side of the MAF.
You're now ready for the fun part. Remove the intake tract and tape the supplied template to the radiator shroud. Line up the inside top cutout of the template with the pencil marks. Make sure the template is centered. Next, use your pencil or marker to trace the inside cutout of the template. When this is done you can remove the template and put it aside. Now you'll need a razor blade knife to cut the shroud. Don't worry, it's not as bad as you think. You can use a straight edge metal ruler to help or do it free hand. It's easiest to cut if you work from the front of the car, between the bumper and hood. The shroud cuts pretty easily if you have a sharp blade. Take your time and be careful not to force the blade past the shroud and into the air conditioning condenser. Once you're done, remove the cut section and put it aside.
The Pro Flow+ kit comes with metal clips that are designed to be installed into the radiator shroud. Their purpose is to give the mounting screws something solid to bite into. Being the lazy bum that I am, I decided to forgo the clips and screw the self tapping screws directly into the shroud. If this should ever prove to be troublesome, the clips are still easily installed. To do it my way, reinstall your intake tract (with the K&N attached to the MAF) and reconnect all your cables. Tighten the clamp on the throttle body as well. Next, place the Pro Flow+ shroud over the filter, against the radiator shroud. The clamp between the filter and MAF should be on the outside of the housing. Once everything is lined up and straight, start screwing in the screws, starting at the outside corners. Be careful not to over tighten! The screws are only going into plastic. Once you've got all the screws in place, go over everything and make sure all the clamps and electrical connectors are installed and tight.
As you can see, the Pro Flow+ installation is easy and straightforward. There was a noticeable increase in seat of the pants performance after installation. I've encountered no problems with the screws coming loose from the shroud. There seems to be no excess debris or water on the filter and the engine runs great. All in all, I wish I would have gotten a Pro Flow+ in the first place and saved myself a lot of trouble. An excellent product all around, even if you have to pay for it!
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