5.3 Turbo build issues!?!?
Feb 23, 2018 | 08:50 PM
#1
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5.3 Turbo build issues!?!?
Looking for some help from you LS turbo guys. Working on a 2012 5.3 Sierra with a BTR stage 2 turbo cam, has a Tricks T4 manifold with a T6 adapter on it, turbo is a Borg S475/96/1.32. Had a 38mm wastegate on it set at 10psi and ran into boost creep issues, no surprise there. Threw on an adapter and a 45mm wastegate set to 7psi, it regulates boost down low but climbs over 10psi as it revs out. I know the adapter isn’t helping the cause but are 5hoping for a little better result. Would swapping to a T6 manifold made for a 45mm gate help to take care of the boost creep or is a bigger gate needed? Thinking about a tighter housing on the turbo too so that would potentially make it worse. Any input before we start throwing parts at it?
Feb 24, 2018 | 10:44 AM
#2
You just need a more gate, cut the 2 bolt flange off and open up the hole and weld the v band for the 46mm gate on the manifold and make sure it's opened up to flow well. Or even put a 50mm gate on it.
Actually, Putting a tigheter turbine housing on the turbo will help your situation. It will increase back pressure and push more exhaust out the waste gate bypassing the turbo. Those big, open BW's are hard to control some times because they don't create enough pre-turbo back pressure.
Actually, Putting a tigheter turbine housing on the turbo will help your situation. It will increase back pressure and push more exhaust out the waste gate bypassing the turbo. Those big, open BW's are hard to control some times because they don't create enough pre-turbo back pressure.
Feb 24, 2018 | 12:04 PM
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You just need a more gate, cut the 2 bolt flange off and open up the hole and weld the v band for the 46mm gate on the manifold and make sure it's opened up to flow well. Or even put a 50mm gate on it.
Actually, Putting a tigheter turbine housing on the turbo will help your situation. It will increase back pressure and push more exhaust out the waste gate bypassing the turbo. Those big, open BW's are hard to control some times because they don't create enough pre-turbo back pressure.
Actually, Putting a tigheter turbine housing on the turbo will help your situation. It will increase back pressure and push more exhaust out the waste gate bypassing the turbo. Those big, open BW's are hard to control some times because they don't create enough pre-turbo back pressure.
Feb 24, 2018 | 12:25 PM
#4
What spring is the gate set at?
What waste gate?
Have you tried a smaller spring exp. 4psi.
Springs are not absolute they are base points to adjust from.
What exhaust size and length after the turbo?
The hole in the manifold where gate bolts to.
Is usually larger then the typical 2 bolt flange.
A little porting on the adapter could help.
You already have a 2bolt gate.
Can easily just add to cross over if other options don’t work out.
What waste gate?
Have you tried a smaller spring exp. 4psi.
Springs are not absolute they are base points to adjust from.
What exhaust size and length after the turbo?
The hole in the manifold where gate bolts to.
Is usually larger then the typical 2 bolt flange.
A little porting on the adapter could help.
You already have a 2bolt gate.
Can easily just add to cross over if other options don’t work out.
Feb 24, 2018 | 01:25 PM
#5
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What spring is the gate set at?
What waste gate?
Have you tried a smaller spring exp. 4psi.
Springs are not absolute they are base points to adjust from.
What exhaust size and length after the turbo?
The hole in the manifold where gate bolts to.
Is usually larger then the typical 2 bolt flange.
A little porting on the adapter could help.
You already have a 2bolt gate.
Can easily just add to cross over if other options don’t work out.
What waste gate?
Have you tried a smaller spring exp. 4psi.
Springs are not absolute they are base points to adjust from.
What exhaust size and length after the turbo?
The hole in the manifold where gate bolts to.
Is usually larger then the typical 2 bolt flange.
A little porting on the adapter could help.
You already have a 2bolt gate.
Can easily just add to cross over if other options don’t work out.
Feb 24, 2018 | 07:55 PM
#7
Started with a precision 38mm wastegate with a 10lb spring and was creeping up past 14psi then i switched over to a 45mm Turbosmart with a 7lb spring and would hold for sec or two then shoot up to over 11-12lbs...have a 4” exhaust and only about 2’ long pipe (fender dump)
. Put a 3psi spring in the gate. See what happens.
If boost still jumps above what you want.
I’d add that other gate into the crossover. Since You already have one.
Put low springs in each.
Connect all vacuum lines The same way.
If there is any boost controller in this set up. Remove it completely for now.
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Feb 24, 2018 | 08:56 PM
#8
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Ok so no down pipe. .
Put a 3psi spring in the gate. See what happens.
If boost still jumps above what you want.
I’d add that other gate into the crossover. Since You already have one.
Put low springs in each.
Connect all vacuum lines The same way.
If there is any boost controller in this set up. Remove it completely for now.
.Put a 3psi spring in the gate. See what happens.
If boost still jumps above what you want.
I’d add that other gate into the crossover. Since You already have one.
Put low springs in each.
Connect all vacuum lines The same way.
If there is any boost controller in this set up. Remove it completely for now.
Feb 24, 2018 | 09:15 PM
#9
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