Turbo Bark

[CGriffith]

I think I "barked" my HX-40 the other day- it sounded bad.



From what understand this is temporary flow reversal in the compressor wheel due to excess boost when you lift off the fuel suddenly.



What exactly does this sound like?

Will this hurt anything?

How do I avoid this with my manual transmission?

Can using a waste gate at the proper setting help avoid this?



Thanks for informing a newbie.

 

[RowJ]

CG

Hard to describe-but if you heard it when backing off throttle,-that's it!

Is not good for Turbo-heavy deceleration load on fan blades. Should be avoided at all times. HX-40's are well known for barking and throwing blades or blade tips. At 100,000+ rpm this is not pleasant!!!

Shift slower-letting off throttle gradually when shifting at high rpm should eliminate problem. Do what ever you have to to decelerate boost gradually.

Wastegate will allow less boost, so drop wont be as severe but I think you can still bark an HX-40 with a wastegate.

Good Luck!

 

[chrleb1]

This can also snap the shaft. It has to do with momentum. The exhaust wheel is a little too big for the shaft and when you bark it, the rpms of the turbo drop drumatically. Picture going from 80,000 - 100,000 to 15,000 in nothing flat.

 

[kaptn]

I usually only bark my turbo when showing off. Lesson: try not to show off. Ya Right! It is something I learned after barking the turbo a few times how not to do it again. Weather jumping out in traffic or finishing a run down the dragstrip. Let off a little slower.

 

[Sticks]

The amount of boost you have built up makes a difference too, though I am not about to find out where that point is. I have barked my HX35 three times now, and all three were when I was hard into it (passing, beating the yellow light, etc) and got off the throttle while still pulling HARD. I have yet to do it while shifting, even with a racing style of acceleration.

 

[fkovalski]

Per CGriffith's original question- What does it sound like?

 

[Mad Bomber]

Sounds like

The bark sounds more like a woof,woof,woof really fast and you hear it on passanger side in the glove box.

 

[fkovalski]

The bark sounds more like a woof,woof,woof really fast and you hear it on passanger side in the glove box.

Is it loud? I do recall instances when I have done things similarly as described by kaptn and sticks. But, I do not recall hearing anything (did I really "bark" the turbo I ask myself. ) I have taken my silencer ring off. But, if the bark is significant I would expect to hear it. Again- I ask my self- "have I ever barked?" I have since amended my driving ways as to not do damage (real or percieved) to my truck. Thanks. -frank.

 

[Mad Bomber]

Sounds like

To me it sounds kinda muffled. I belive you really have to be pushing close to 30PSI before it will happen.

 

[GFrance]

barking the turbo

So thats what that sound was. The other day I put some new skins on and when I left the tire store I was showing off and tromped on the throttle then let off suddenly heard the noise & didn't know what it was. So like a dummy I did it again to try and figure out what that was. Hope I didn't hurt anything.

 

[Mad Bomber]

GFrance, I would not try to do it.

 

[GFrance]

Thanks for the advice E Wagener just had no idea what the noise was. Don't want to be damaging anything before I go up to see Bill K. I'll be droping enough $$$ up there the end of the month.

 

[Mad Bomber]

Psi

GFrance, come join the local club in the NW go to www.NWBombers.com it's a free web site. We do alot of get togethers, and we'd love it if you were able to join us. Eric

 

[RobertBolinger]

Is it possible to bark a stock truck?

 

[GFrance]

E Wagener

I'am over on the nw bombers site. You will see my post as TankerYanker over there.

 

[Mad Bomber]

I just make sure to tell EVERYONE it's there.