Running to much boost. How can I lower it????

[FLYBYU]

gutting the muff

Ok thats just getting personal. LOL

It's posted on here somewhere.

 

[machz69]

gutting the muff

Ok thats just getting personal. LOL

It's posted on here somewhere.

lol.... yes we are all looking for the same thing

 

[FLYBYU]

Go with the excell exhaust. I have recieved many compliments on the way it sounds

 

[pdrmike]

My exhaust is gutted and has the 3 exit pipes. Is there any other way I can drop boost. Maybe open one of the ports on the intercooler or bleed some off the turbo itself on one of the lines????

 

[mbarryracing]

Maybe open one of the ports on the intercooler or bleed some off the turbo itself on one of the lines????

Bad move to create a leak in the intercooler or charge tube as that will just cause the turbo to spin faster and overspeed the bearings to compensate while still making the same boost...
I find it funny because alot of guys are struggling to make enough boost because of leaks, and you have the opposite problem.
Keep looking for a cause of the high Back Pressure.

 

[aja636]

double check the wastegate arm, make sure its not bent, check the exhaust pipes, maybe a hunk of ice crushed one, Some things strange you should have no problem getting the boost you want. check all the lines for your boost controller for a pin hole or a cut hose?? Check to see if any of the boost lines are clogged. I don't know

Just throwing some "out of the box" ideas at you.
I just went through something that didn't make any sense as well, very fustrating

good luck

 

[2XM3]

just as a test, remove rod and tie the wastegate full open, see if you still get 14 psi??? then for test #2 hook back up and pull your muffler, do you still get 14 psi?

 

[pdrmike]

quote]

Bad move to create a leak in the intercooler or charge tube as that will just cause the turbo to spin faster and overspeed the bearings to compensate while still making the same boost...


Just trying to figure something out for myself. Doesn't the Turbo produce it's maximum efficient psi(in my case with a 2854r, 15psi) at all times, and we have the wastegate system to bleed off what we are not using???? If this is true, (and I'm not saying it is) what will cause it to spin faster if I bleed off in other locations?? Thanks for all the help and responses thus far, Mike

P.S. Wastgate is tied open still, will try exhaust next.

 

[mbarryracing]

Mike, these turbos DO NOT have ANY mechanical limiting or governing for shaft RPM. They are only pressure sensitive, meaning they will rev to the moon to build boost if they have to, as long as they have the required exhaust backpressure to drive them... the reason we take the exhaust pressure AWAY from them with wastegates, to limit the boost on the compressor side...
And anyone who tries to control boost level on the compressor side should get kicked in the chipmunks!
Example: If you blow off the intercooler or charge tube while at WOT, the boost drops immediately with the loss of restriction but the turbo just spins faster and faster to try to build boost back up, eventually overspeeding the bearing, burning the oil wedge away from them and smoking your center section.
Look at it like breaking a drive shaft in a drag car while under full load without a rev limiter... parts scatter EVERYWHERE!

 

[pdrmike]

Ok, I took the exhaust off and took it for a spin(wastegate still wide open) and still no drop, still running 14psi.. I think we are running out of ideas.

 

[rxrider]

I assume the sled runs exactly the same between runs no matter what you do to try lowering the boost. Can't think of anything else than the turbo is too small for your application not allowing enough exhaust gas to escape out the wastegate even when wide open, thus causing too much exhaust gas to be routed thru the exhaust turbine. You may have to get the WG ported to let enough exhaust pressure away from the exhaust turbine. Just my 2 cents, I'm puzzled.

 

[machz69]

Ok, I took the exhaust off and took it for a spin(wastegate still wide open) and still no drop, still running 14psi.. I think we are running out of ideas.

wow... not sure what to tell ya..the only thing i can think would be like they said above, some sort of blockage. where are you taking your lbs readings from?

 

[pdrmike]

Was getting my reading from the intercooler, but talked to Ted Jannety and he told me to go between throttle bodies and cylinder head, so I tied one of the gauges into that location, but still reads the same.

 

[FLYBYU]

I think your actuator is just bad and is not opening. i bet if you pin the waste gate open and go out for a ride, you'll barely make any boost if any. if you do, your flap is damaged

 

[machz69]

I think he has it wide open now