Turbo over spool
Thread Starter
Registered User
Joined: Apr 2004
Posts: 169
Likes: 0
From: Utah
Turbo over spool
Howdy,
So did my first pull up a good hill after Gauge and Exhaust install over the weekend. I was pulling Daniels canyon east of Heber, UT. I noticed during the pull that my boost would bounce between 25LB and 20 LB. Did this about 3 or 4 times right in a row. After my auto down shifted. During this short period I lost some of my momentum. Is this what is considered over spooling? If so is this bad? How do I control this?
I heard the turbo during this time correlating what I saw. I never heard this when I had no gauges and 3in straight pipe. So, I am leaning towards this is the first time I experienced this.
So did my first pull up a good hill after Gauge and Exhaust install over the weekend. I was pulling Daniels canyon east of Heber, UT. I noticed during the pull that my boost would bounce between 25LB and 20 LB. Did this about 3 or 4 times right in a row. After my auto down shifted. During this short period I lost some of my momentum. Is this what is considered over spooling? If so is this bad? How do I control this?
I heard the turbo during this time correlating what I saw. I never heard this when I had no gauges and 3in straight pipe. So, I am leaning towards this is the first time I experienced this.
Registered User
Joined: Apr 2004
Posts: 133
Likes: 0
From: Westminster, MD
Newb advice here, but from what I understand the factory turbo runs out of its efficiency range around 35 pounds of boost, so I would say your doing fine between 20 and 25. FWIW, I can peg my 40 lb. boost gauge with what I have in my sig. HTH
MIke
MIke
Registered User
Joined: Jan 2002
Posts: 331
Likes: 0
From: BFE Oregon
How quick was the bounce between the pressures?
My buddies Ford does this under load really bad. On his its caused by surging, barking, cavitation whatever you want to call it because of the design of the compressor wheel.
My buddies Ford does this under load really bad. On his its caused by surging, barking, cavitation whatever you want to call it because of the design of the compressor wheel.
Chapter President
Joined: Feb 2002
Posts: 6,102
Likes: 2
From: Red Deer, Alberta Canada
I agree with Bill (again). Probably the auto shifting in and out of lock up.
The problem Cummins4life states is flutter or surging. The turbo is at high boost and low turbine speed causing some slippage. My 93 CTD did the flutter as well with the 12cm housing upgrade. Not a good thing either.
The problem Cummins4life states is flutter or surging. The turbo is at high boost and low turbine speed causing some slippage. My 93 CTD did the flutter as well with the 12cm housing upgrade. Not a good thing either.
Thread Starter
Registered User
Joined: Apr 2004
Posts: 169
Likes: 0
From: Utah
Ok thanks for the replies,
It was prob. over about a 5 sec. time frame. But could have been shorter. I don't have a stop watch inside the cab. hehehe. I thought it could handle over 30lbs. The 4 inch allowed me to go from 23lbs to 25. I don't see 25 unless I am in second and on a pretty good hill. Hmm, defueling does make sence. I did not see the RPMS, but I don't have the 3000GSK yet. Waiting til I can upgrade tranny and install a #10 plate at the same time.
It was prob. over about a 5 sec. time frame. But could have been shorter. I don't have a stop watch inside the cab. hehehe. I thought it could handle over 30lbs. The 4 inch allowed me to go from 23lbs to 25. I don't see 25 unless I am in second and on a pretty good hill. Hmm, defueling does make sence. I did not see the RPMS, but I don't have the 3000GSK yet. Waiting til I can upgrade tranny and install a #10 plate at the same time.
Thread
Thread Starter
Forum
Replies
Last Post
Luvnacumns
3rd Gen High Performance and Accessories (5.9L Only)
29
May 28, 2007 09:47 PM