It sounds normal to me. The variance in rpm you hear is the grid heaters cycling. They will draw the engine down a bit when they kick on. Mine does the same thing.
JB

 

I put on an S&B CAI got rid of factory air box & tube,can hear turbo spool now

 

It almost sounds like the E B comes on then goes off. Sometimes it will do it and sometimes it will not.


Sluggo can you put up a link to where your S&B CAI from.....Thanks HP.

 

Next time it does that, watch your tach. More than likely it's kicking the exhaust brake off when the grid heaters kicking on draw it down below 1100 rpm. The exhaust brake is set to kick off at 1100 rpms from the factory.. When you turn your high idle on using the cruise control, you can use the resume/accelerate button on the right side of the wheel to run it up to 1500rpm, and the coast button to drop the rpms, both in 50 rpm increments. If you're up over 1100, it should stay on.
A guy I work with just bought a new dually. He panicked when he saw the volt meter head south and the interior lights go dim the first time the heaters kicked on for a cold start. It was pretty funny.

 

That is what it does. Thanks HP.

 

You're welcome. Glad I could help.
JB

 

yeah mine does that to and just set it around 1300 rpm and it dont seem to bother it then

 

I removed my intake baffle at the start of trailer season, last spring. As well I picked up an intake box from the wreckers. I cut a 4 1/4" hole in the bottom of the box and installed a 4" flange. I ran an aFe drop in filter at first but later switched to a K&N. This winter I am going to rig up a ram air system to the bumper. The above mod produced more throttle response and about 1 to 1.5 more mpg.

 

Do you have any photos of what you done?

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Well I do not have 7k on my truck yet and nothing done to it. And all ready I got something wrong. My E.T.C light is on. What could it be?

 

I did not take any photos. When you lift my truck's hood, it all looks stock. The flange (a modified toilet flange) in the bottom of the air box, sticks straight down about 3" below the bottom of the box. There is a drain hole in the centre bottom of the box which was used as a pilot. The flange draws air ahead of the fender liner. If you look at the Volant site, they show a ram air vent and tube that draws air from the centre of the bumper. Mine will be similar or one of theirs modified.
The tube baffle is pictured above. Once you get the tube off of the turbo and the connectors off of the tube, the baffle and surrounding insulation pulls out of one end of the tube. Make sure that all the clamps are tight when you reinstall the tube. I'm going to wrap the tube with aluminum furnace duct tape, just to repel a little heat. It should be noted that I did this with a box and tube from a wreck. The stock box and tube with all the sensors and filter is hanging in the garage if needed.