Well I just finished my CCV mod and installing a 6637. I don’t know if its
because I can hear the engine better but I’m wondering if this is normal.
When I run the engine up in RPM’s and then let off the gas fast it sounds like
the turbo sneezes, is this normal? If I let off the gas slow it makes a slow
sneeze sound.

thanks in advance
Patrick

 

That's normal, don't worry about it.

 

Completely normal like Chase said.

 

awesome i love the sound i just wanted to double check that all was okay

 

Yeah, whats happening is the turbo is making lots of boost at high rpms, once the truck shifts or you let off the pedal, the rpm drops and the engine can't ingest all the boost, so it comes back out of the 6637 in a whoosh sound. It was happening with the old setup you had, just couldn't hear it because it was closed in.

 

I Love That Sound, It Gets Kinda Addicting. Now that you have the 6637 you will find yourself mashing on the skinny pedal just to hear the turbo!!

Wow, I just hit 1,000 posts but in camparison Rick is at 8,008. Nevermind I'll just crawl back under my rock!

 

Then when you add the DP Tuner, you mash on it, look in the mirrors for the black cloud, then enjoy the sounds of the turbo singing

 

I didn't even notice I went over 8,000 post. I think I had 8 productive post in all that. Just like this one here, no value at tall.

 

Maybe your turbo has allergies...??? HA!


Talk about useless responses - I'm just as guilty!


Like the guys said above, it's normal.

 

1) The whoosh sound is turbo surge and it's doing some damage to the turbo bearing every time you hear it so don't be snapping your foot off the throttle too quickly!

2) It's a fact that a driver in the cab can't hear a whoosh with the stock air box or with an AIS air box and that should be taken as evidence that the whoosh doesn't occur with these setups unless someone can prove otherwise!

3) We need to get someone with a stock air box to tape a microphone to his lid and make some recordings. As I always say never assume anything that can be easily measured!

4) Based on some late breaking CFM vs Inches H20 restriction data that's been posted I think there's a possibility that the reduced restriction of the 6637 compared to the stock setup is actually causing the whoosh or at the very least intensifying the whoosh by causing the compressor wheel blades to stall sooner as the compressor wheel rpm ramps down after letting off the throttle too quickly and that explains why I started hearing a whoosh right after I switched to a low restriction K&N cone and then why 50K miles later my turbo bearing was worn out!

 

WOW Rick, that's an average of 11 posts every single day of the week!!! Way to go.

Good info Gene. I never noticed it at all until I went with the Tymar. Personally, I don't like the swoosh back into the air filter from the turbo. It just doesn't sound like it could be doing anything any good!

 

Congrats!! I went over 8k a while back, but I recently got my 7th greenie...

Gotta love the 6637... Notice any differences in performance or mileage yet?

 

i could hear this befor but it was not as loud, my guess is that the intake is
more open so it is easer to hear. plus the bigger filter means there is less reisitance too.

 

Exact same thing happens with a stock airbox and the AIS.

False. My parent's have a 2003 7.3L still running the stock intake. You can very faintly hear the whoosh sound, but it's the exact same noise and the exact same duration as having an open element air filter. My parent's never even knew it until I pointed it out. Now they can hear it if they listen for it. The stock airbox muffles the noise, but doesn't prevent it from happening. It also doesn't prevent surge. It's much easier to tell when surge is happening when you have a bouncing boost gauge in front of you, even though you can't really hear it easily with the stock intake.

Good luck with that.

False, the whoosh sound is specific only to the stock turbo, which is the Garrett GTP38. All other turbos that you can possibly bolt up to the Powerstroke make completely different sounds, regardless of intake type. And I know why your turbo failed with the K&N, and it wasn't the shape of the filter that caused it.

Bingo. All the turbo noises, compressor stall, surge, etc, all exist even with the stock airbox. Changing the intake to an open element filter doesn't change the fact that those issues weren't present before. It's all part of the stock turbo and it's design limitations. The stock turbo is very susceptible to surge, and it's extremely noisy. The stock airbox does a very good job at muffling those sounds.

 

Gene, my stock air box does that, after i installed 4 inch exhaust it made it even louder when it does that. Stock air box does that.