If you own a Corvette that has had an intercooled Magnuson Supercharger system installed and you think all is well under the hood of your pride and joy, you may be in for a big surprise.

When inspecting my 2003 ZO6 Corvette after winter storage, to my surprise I found a kink in the heat exchanger return hose passenger-side connection at the base plate behind the blower drive belt at the fire wall. After a more intensive inspection of the same heat exchanger return cooling hose routing, I found a second severely kinked area where the hose makes a bend for its routing to go under the frame around to the upper barb of the heat exchanger.

This hose is molded for its 90-degree bend under the passenger side head light location for the upper barb of the heat exchanger connection, but it is not molded at the other end. With my ZO6, this hose was not wire-tied and slid down the inner fender making almost a 90 degree bend where the hose was laying on the sway bar before making its bend under the frame rail around to under the passenger side head light and through the radiator shroud.

With my ZO6, I estimated a 75% to 80% restriction in volume at the sway bar location and a 50% restriction at the passenger side connection at the engine blower base plate passenger side connection.

To correct the problem I bought a 3-foot length of 3/4 in. ID heater hose that had stainless steel coil spring that you can make any angle you need up to 90 degrees and will not allow the hose to collapse. I cut out the kinked area at the sway bar location and replaced with about a 60-degree bend with the coil spring on the outside of the hose.

I bought a piece of 3/4 OD x .065 wall .620 ID aluminum tubing from McMastercar (part no. 89965K92 at www.mcmaster.com, phone 330-995-5500) and made two 3-inch long nipples to make my hose connections. Make sure you use aluminum tubing for your nipples so they will not contaminate the 50/50 Dex-cool coolant. Use a #10 stainless steel hose clamp for your hose connections. You will also need to drop the sway bar down at the bushing locations to make room to work. Also, make sure you file and fine-sand the outside and inside ends of the cut aluminum 3-inch nipples.

At the connection of the same heat exchanger return hose at the blower base plate passenger side connection, I simply cut off about 2 inches of the kinked hose and reinstalled it. After you have replaced your restricted hose with the new heater hose section, make sure you wire-tie the hose in two or 3 locations to eliminate the possibility of the hose sliding down the inner fender and restricting the coolant flow. Be careful not to pull the wire ties too tight as to restrict flow rate.

After speaking with a Corvette Tech at Magnuson Products, he told me that you most need 100% of the cooling capacity when the outside air temp is above 75 degrees for the coolest intercooler temp for maximum horsepower gain.

The bottom line is . . . don't assume that the cooling system for your supercharger is flowing at 100%. Check every inch of your hose routing for kinks and restrictions. It could be costing you a major horsepower loss, especially if the outside air temp is above 75 degrees.

Just because you have had your system professionally installed doesn't mean that your cooling system routing has no restriction problems. It could be costing you a significant horsepower loss.