Initial Alterations

My rough initial measurements indicated a slight clearance problem between the end of the filter and the upper radiator support and the top of the fan mounts. I decided cut a small amount of material from both of those areas. It turned out that it didn't need to be done to the radiator support. Live and learn! It's hard to see in the above picture, but I also enlongated the bolt holes in the radiator support slightly, towards the engine. This allowed the radiator support to move slightly forward, eliminating having to remove any material. The little sections I cut out of the top of the fan mounts (below) were done last. When everything was assembled and installed, I had to push the filter slightly towards the engine to fit behind the fan mounts. Looking from the side, I got the filter in what looked like the correct position and marked the fan mounts around the bottom of the filter with chalk. I used a small hacksaw blade to cut away just enough material so the fan mount bolt heads (you can't see them) weren't protruding. The notches in the top of the fan mounts also provide support for the end of the filter. Not shown: I applied some heavy black tape to the edges of the notches to prevent scratching of the chrome end of the filter.

The Corvette Duct Assembly

The Corvette duct has provisions for an air tube and air inlet temp sensor, just like the stock elbow. Note which way the stock temp sensor faces, in relation to incoming air flow, and then carefully remove it from your stock elbow and install it in the Corvette duct. Note: You can remove the fixed size clamp and throw it away. You can see that the duct comes with a locating notch, for the MAF sensor. It is offset from the vertical position and you'll have to cut another notch for your MAF sensor to be positioned correctly. FYI, the part number for the temp sensor is the same in LT1 equipped B & F-Body's.

The MAF Sensor

The first problem that presents itself is the 3.25" size of the inlet and outlet of our stock MAF sensor. The inlet ID of the Corvette duct is 3.50". Why would GM cut down the air flow through the MAF sensor? Only in full-size cars? FYI, the inlet and outlet size of LT1 MAF sensors in Corvette's, Camaro's, and TransAm's is 3.50". The rubber adapters on our stock MAF sensors seem to be perfect for adapting the 3.50" Corvette duct inlet and the 3.50" base of the S&B Powerstack filter. It works, too, but when using the rubber adapters in their stock form, the overall length of the assembled parts is way too long. I then hit on the idea of cutting off the outside half of the rubber adapter, retaining the inside half to adapt the dissimilar sizes, as shown in the pictures above and below. You'll also notice that the remaining part of the rubber adapter on the exit side of the MAF sensor has been trimmed to be flush with the edge of the outlet. This was done to prevent interference with the air inlet temp sensor when finishing the final assembly.

The S&B PowerStack Filter

The S&B Powerstack filter appears to be a quality product and looks just like a K&N in the filter area. The difference is the added air inlet area in the nose of the filter. K&N also has a new product called the "XStream Air Flow Top", which looks just like the Powerstack filter. They are supposed to be available in the very near future.

The base flange of the S&B Powerstack filter is 1.75" long. It needs to be shortened to 1.00" as shown in the picture above. You can then cut the MAF sensor locating notch 180 degrees from the metal strip in the filter. You can see the metal strip framed in the notch I cut in the base flange.

Final Assembly & Pictures

The final assembly is pretty straight-forward. Assemble the Corvette duct, MAF sensor, and filter and tighten the clamps. Slide the outlet end of the Corvette duct on the throttle body and tighten the clamp. Plug the MAF harness extension into the stock connector and then into the MAF sensor. Plug the inlet air temp sensor harness into the sensor. Push the Optispark air tube into the hole provided in the duct. Double check the tightness of all 3 clamps and you're finished with the basic install. Now, take a look at your installation from the front of the car. You'll notice that the open section at the front of the filter is positioned with its bottom edge approximately level with the top of the upper radiator support. I have cut a portion out of the center of the front hood seal to encourage a flow of air over the top of the upper radiator support into the front of the filter. Just look up at the seal and then down at where the filter is located and common sense will tell you how wide of a piece to cut out. Once you've removed a section of the seal you are finished.

In the above picture you can just make out the end of the filter sitting in the notches cut in the fan mounts. You can also see that I didn't have to remove the material from the upper radiator support.

Another view of the finished installation. I took the picture before the clamp was put on the filter.

View from the front. Neat looking installation, don't you think? I get a lot of positive comments.

My Comments

This installation may not be for everyone. I have seen variations of it on quite a few B-Body's, including the Impala SS, and it has been on my car for over a year, here in the South. Questions have been raised about dirt, water, and pulling hot air from below. I can only say, from my experience, that I haven't had any trouble with dirt or water, so far. I don't know what to say about pulling hot air from below. I drive my 9C1 50% of the time and, so far, so good.

What I have noticed is an improvement in throttle response and a seat of the pants feeling that the engine "pulls" better when you get aggressive with the gas pedal. If I've heard it once, I've heard it a hundred times, "the B-Body LT1 likes a straight, short, intake path, with the MAF as close to the throttle body as it can be, just like its smaller F-Body relatives".

I have a lot of fun "tinkering" with stuff. I like the way this setup looks and the car feels "peppier" to me. Don't do as I do. Evaluate what's available out there, or, even better, build one for yourself. It's fun. Enjoy!

Your Comments?