Electric fans helping MPG???

Hey guys, Got a question for yaz, My friend Has a 06 Silvy crew cab, and he has the 5.3, but when you open the hood theres room to work!, theres no fan shroud, because it has electric fans! Unlike my 99', which is belt driven, does this help with gas mileage, or why did they did this?? what are the advantages of switching. I might just switch my self if there is a huge benifit

It takes 12 +/- RWHP to drive the mechanical fan. It 1/2 RWHP to drive an electrical fan. You do the math. Another point is that electrical fans are more efficient. You can turn the fans on and off precisely when needed unlike the mech that is set to a wide tolerance. When you are driving down the road the flow of air is taking care of the radiator and no fans are needed. When you idle the fans will turn on at a certain temp and then the fans on high if a higher temp is received. Unlikethe mech that will go on somewhere around the temp and even in cold weather.

It is easy to change the mechanical for a set of electric. Find a set of LS1 fans from a camaro/Trans AM from '98 to '02, if you have a tune or someone who can program the PCM set pin 42 for the temp desired 180* on, and get a harness with relays to satisfy the A/C on condition. Nelson Performance has the harness, you need a programmer and the rest is cake for 1/2 to 1 mpg.

Sorry for being long winded,
Good Luck

But there is no point in taking off the shroud, it makes the cooling more efficient because it rams the air through the fan

The LS1 fans have a shroud that they come in. If you keep the old shroud it pushes the air into the engine heating it up. Using the gap that the new shroud creates between the block and the shroud allows some of the hot air to get away from the block. Also it allows you easier access to the engine bay. The existing shroud can not "Ram" the air from behind the radiator. The radiator wall will only allow a certain amount of air into the radiator through the hole.

Just my :2cents: