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1995 6.5 turbo silencer

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Old 08-20-2015, 01:47 PM
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Default 1995 6.5 turbo silencer

How do I remove the turbo silencer to get more whistle? And where's the silencer at?
 
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Old 08-20-2015, 02:28 PM
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I'm pretty sure the GM series turbos don't have a silencer. It's just that the factory boost setting is low, therefore the turbo doesn't work enough to make a whistle. You can try a high flow air filter and listen for a whistle. But more than likely, youll have to raise the boost to make it whistle. My GM8 turbo did not make a sound when it was set to 4 psi. After making a turbomaster, and setting it to 12 psi, it now whistles from 4-12. Hope this helps.
 
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Old 08-20-2015, 02:45 PM
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Already, how did you raise the boost? I'm a newby to 6.5's.
 
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Old 08-20-2015, 04:07 PM
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On 94+ trucks, the ECM will see too much boost if it hits 10psi and will defuel. So you could not go over 9 psi without a custom tune. A "turbomaster" is a mechanical spring-loaded wastegate actuator, used for setting up how much boost the user wants.
I made my own, and if my picture embedding works, should look similar to this.




It would be best to install a boost gauge to fine tune the turbomaster so you don't get above 9.

With the turbo set 6-9 psi, the turbo should whistle nicely. I have mine set to 12, and starts whistling around 5-6, and I can here it in the cab, pretty loud.


EDIT: Since yours is a 95, you probably have the horizontally mounted vacuum pot, not vertical like GM8.

and sorry, I cant figure out how to resize the pic.
 

Last edited by cviola2005; 08-20-2015 at 04:12 PM.
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Old 06-23-2016, 02:21 PM
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Originally Posted by cviola2005
On 94+ trucks, the ECM will see too much boost if it hits 10psi and will defuel. So you could not go over 9 psi without a custom tune. A "turbomaster" is a mechanical spring-loaded wastegate actuator, used for setting up how much boost the user wants.
I made my own, and if my picture embedding works, should look similar to this.


It would be best to install a boost gauge to fine tune the turbomaster so you don't get above 9.

With the turbo set 6-9 psi, the turbo should whistle nicely. I have mine set to 12, and starts whistling around 5-6, and I can here it in the cab, pretty loud.


EDIT: Since yours is a 95, you probably have the horizontally mounted vacuum pot, not vertical like GM8.

and sorry, I cant figure out how to resize the pic.
I just inherited my grandpa's 93, so I wouldn't have to worry about a custom tune? also is 12 about as high as you would recommend going, or is it safe to go up to say 15?
 
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Old 06-23-2016, 07:25 PM
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Correct, 93 is completely mechanical, no computer for the engine.

With a stock motor, don't go up to 15. Don't go past 12. I had mine set at 12 for a long time with no problems. One day, I turned it up to 15 and all was well for a day or two. Then it spiked to 16, and i broke the crankshaft.


Now I have new crank, new heads, and arp headstuds and I'm hitting 20 peaks and holding 15-18 on hills.
 
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Old 06-24-2016, 02:15 PM
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16 and you broke the crank??? that's down right scary! and not that much boost. makes me kinda scared to do anything to this motor :/
 
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Old 06-24-2016, 04:24 PM
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WELL.... A multitude of things lead to that. It wasn't a stock motor when that happened.

All in short, bored 0.020" over and the intake, heads, exhaust manifolds, and turbo exhaust inlet were all port matched. The most important factor to the crank breaking was that is was turned down 0.020". Also, the day before the break, I had taken out the #1 injector to check for coking (was running WMO homemade fuel, and by calculation higher BTU output than standard D2 diesel) and I cleaned it to see how much coke buildup was on it.

At the time of the break, I was slowing down because the guy in front of me was turning. I looked in my rearview to see the trailer pulling guy behind me and it didn't look like he was slowing down at all. So I floored it in 3rd gear (proper gear for the speed). It was nearly 3600 rpm and I was pushing the clutch in to shift when BANG, clank, clank, clank. I managed to pull over in time to get out of the other guys way.

It broke in between the #1/#2 rod journal and the main journal behind it.


All in all, 16 psi spike in boost, turned crank journals, 1 cleaned injector, and a little over revving, I believe, all played a factor in the crank breaking.



NOW, I have ARP head studs (which I now swear by because new torque to yield bolts allowed head gasket to blow at 14 psi boost), and a new crank (not reman turned unit). A Holset HX35W turbo build 20 psi easily holds 15-18 on heavy hills and I have yet to have a problem, the thing runs amazing.

If you want to build, I would definitely recommend ARP head studs and a better, more efficient turbo like the HX35W. If you want more information, PM me.
 
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Old 06-24-2016, 08:36 PM
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Originally Posted by cviola2005
WELL.... A multitude of things lead to that. It wasn't a stock motor when that happened.

All in short, bored 0.020" over and the intake, heads, exhaust manifolds, and turbo exhaust inlet were all port matched. The most important factor to the crank breaking was that is was turned down 0.020". Also, the day before the break, I had taken out the #1 injector to check for coking (was running WMO homemade fuel, and by calculation higher BTU output than standard D2 diesel) and I cleaned it to see how much coke buildup was on it.

At the time of the break, I was slowing down because the guy in front of me was turning. I looked in my rearview to see the trailer pulling guy behind me and it didn't look like he was slowing down at all. So I floored it in 3rd gear (proper gear for the speed). It was nearly 3600 rpm and I was pushing the clutch in to shift when BANG, clank, clank, clank. I managed to pull over in time to get out of the other guys way.

It broke in between the #1/#2 rod journal and the main journal behind it.


All in all, 16 psi spike in boost, turned crank journals, 1 cleaned injector, and a little over revving, I believe, all played a factor in the crank breaking.



NOW, I have ARP head studs (which I now swear by because new torque to yield bolts allowed head gasket to blow at 14 psi boost), and a new crank (not reman turned unit). A Holset HX35W turbo build 20 psi easily holds 15-18 on heavy hills and I have yet to have a problem, the thing runs amazing.

If you want to build, I would definitely recommend ARP head studs and a better, more efficient turbo like the HX35W. If you want more information, PM me.
Hey buddy how's life treating you nowadays?
 
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Old 06-24-2016, 08:38 PM
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Originally Posted by 6.5jones
How do I remove the turbo silencer to get more whistle? And where's the silencer at?
Yes as civiola said there is no silencer ring this is a internet myth.
 


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