Was pullin new TT 11500lbs when better half asked ..."was that normal?" (she likes the turbo sound... silencer mia and areo ) but we wuz pullin from on ramp to highway I hit about 50mph wuz a tad hard on the go pedal when turbo started to "bark" then wosh wosh! I let off pedal and eased up to highway speed 65mph...wondering if it was tranny slippin leading to increased rpm ..or... turbo surge (same thing no !?)
Wondering if I damaged anything or if I could be headed towards something bad?

Pre-turbo EGTs were 1400-1450deg boost up near 25lbs at the time. After getting to crusing speed EGTs were around 800-900deg, boost 9-9.5lbs.

 

you dont need to do it too much. . it will snap the shaft in the turbo if you do it enough/too hard. it happens more with the auto's than the manuals, and I think it may have something to do with the silencer ring. . .install it and see if it will do it again. what is happeneing is the drive pressure of the turbo is being overcome by the intake pressure and the turbo actualy stalls and spins backwards.

BTW, Ive barked my turbo at only 10psi with my TST crunk

 

Mine barks every time I turn on the air conditioning!

 

Sorry but seeing the phrase "turbo bark" brought this pic to mind.

 

Hahahaha Speakle. Also Hmm.... turbo bark. Not sure if i've had that or not. What exactly does it sound like? Also question. Could it also possibly be caused by the pressure in the turbo building up so quick that the waste gate dumps the pressure? I was talking to a buddy of mine, he drives a 03 stroker 7.3L with a banks turbo,straight piped. He said sometimes if he's hauling a load (he has a stick btw) and his chip kicks up. His turbo's waste gate is limited to about 28, it'll open up make kind of a funky sound and he'll loose power for a second then everything will pick back up. He checked all of his intake rubber elbow's and connectors and such and they're all fine. It's just that his heavy load (swathers and tractors such and such) requires so much power to pull the grade at a certain speed (he usually fly's pretty good) that the turbo starts sucking more air than the wastegate allows, it dumps it, when it dumps it pressure is lost. Lost power. Turbo picks back up. I know cummins and international's turbo's are different so is it possible that that is what is going on? not saying drew is wrong. Just seems plausible with him pulling a load and putting the load on the engine.

 

that is just the compressor kicking on. . .perfectly normal.

barking the turbo doesnt happen unless you let off the throttle while loading the engine and turbo. that 03 ford is doing that from the wastegate opening up too much and the turbo surging which means his turbo is too big for his application.

 

Drew, I was into the throttle tryin to match on coming traffic when she "barked" then kinda a "wosh! wosh!" seemed to be a little sluggish at the time of barking then after things quieted down the power came so much so I had to let off as i was about to run a unloaded POS over!! Its more pronouced when I'm loaded up and a little heavy on the go pedal (since I have learned to ease into that final gear), I have had her "bark" once or twice trying to teach the odd "non-Cummins" a lesson!

 

what happened was your tranny shifted, probably from 2nd to 3rd. the sudden reduction in engine RPM's also lowered the drive pressure of the turbo causeing the intake side pressure to overcome the exhaust drive pressure and the turbo spun backwards for a moment.

the lack of power was due to the turbo no longer suppling air, the MAP sensor seeing this and reducing the fueling to to match boost pressure. when the turbo finaly got it's drive pressure back it was off to the races.

 

mine does it often... makes me nervous every time it happens. I'm wondering if a phat shaft turbo would be more durable?

 

Ive heard they dont bark as much as the stocker holsets. you can still get them to, however the shaft is beefier and can handle the twisting forces better.