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Discussion Starter #1
I installed my boost elbow that I bought on ebay over a month ago. But I can't seem to get the boost to stay below 30psi when in OD, it will easily hit 38-40psi when in OD. I have the allen screw as loose as possible, any looser and the engine vibration will let it unscrew itself with the spring pressure. So right now I can almost unscrew it using my fingers and no tools. What am I doing wrong?
 

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the advantage of the elbow is so that you can restrict flow going to the wastegate actuator. Restricting this flow fools the wastegate into seeing less boost than the turbo is actually creating. Stock turbo is wastegated at around 20ish psi, in return, the stock turbo will not create more than 20ish psi. If you add an adjustable boost elbow, you will be able to restrict that 20ish psi going to the wastegate down to lets say 10 psi. Since the wastegate is seeing only 10psi (and being as it is set at 21psi) you still have another 10psi that you can build through the turbo (giving you lets say 30) before the wastegate opens. So in essence to create more boost(and have the wastegate open later screw the alan head in) to create less boost and have the wastegate open earlier screw the alan head out, i dont think your doing anything wrong.. i think you got it right.
 

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my personal favorite is a small brass valve and some brass fittings, u install it instead of the boost elbow and it allows almost perfect blow-off point adjustment...
 

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my personal favorite is a small brass valve and some brass fittings, u install it instead of the boost elbow and it allows almost perfect blow-off point adjustment...
can you explain more how to do this.... maybe some pics
:drool2:
 

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^^ditto this has my curiosity piqued
 

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Discussion Starter #6
Sounds like I have been actually adjusting it the opposite way. I have been unscrewing the allen head in an attempt to reduce boost pressure, with apparently no affect. But what I need to do is actually screw the allen head in more to reduce boost. Sound right?
 

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no im pretty sure you were doing it the right way, the further you screw it in the more it restricts the air going to the wastegate, so think of it like this if you would plug that hole entirely the wastegate would open way later, actually wouldnt open at all
 

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Discussion Starter #8
Then why does it want to go above 30 psi so easily? Is it common for the waste gate actuators to go bad? What is this about almost perfect blow off point adjustment? I bought the boost elbow for $20 on ebay and might as well have just plugged the line for as useless as it has been.
 

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your wastegate very well could be frozen shut tho, its simple to pull your turbo off and then remove the housing and see whats going on.
 

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get an 1/8" npt brass nipple.... an 1/8" npt brass valve that is female/female and a nipple that is 1/8"npt x 1/4" tube screw it all together and u have ur custom "adjustable boost elbow"
 

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Is it common for the waste gate actuators to go bad?
It's more common for the wastegate to get carboned shut.
The actuators last very well until someone tries to test one with 80 psi compressed air.
 

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Discussion Starter #12
Ok so I put the stock elbow back in place and I checked that the waste gate wasn't stuck. I took it for a drive and it performs the same as before. So could carbon have actually blocked the wastegate hole? Also how much turbo shaft play is ok? I thought I didn't have any shaft play before I pt the boost elbow in, but it may have been that I didn't grab the end of the turbo shaft firmly enough. Becuase now I can get it to go up and down a little bit and side to side a little bit too. It doesn't rub, even if I try to make it by pushing on one side while turning it. Think its possible I over spun the turbo by hitting 40psi a few times? What years of stock turbos would be a direct swap or upgrade with minimal to no modifications? What about upgraded turbos? I still want quick spool. Is the HX40 the ticket? Which ones to avoid on ebay due to being chinese junk? Thanks
 

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Discussion Starter #13
Also what is the max boost the stock head bolts can handle before studs?
 

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Side to side play is ok as long as the wheel doesn't rub.
Fore to aft play is bad.
 

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Also what is the max boost the stock head bolts can handle before studs?
its anybodys guess, some people have been running 50 psi+ on a stock head gasket for a while, ive been doing 40psi on stock gasket and havent had any issues, but if you retorque the bolts you should be pretty good for a while
 

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Discussion Starter #16
Ok I ordered a holset rebuild kit. I didn't feel like messing with modifying my down pipe for a HX40, nor spending $1000+ minimum for an upgrade and the turbo hasn't rubbed so $51.80 shipped sounds like a good deal. I have rebuilt a few before and always ended up with no shaft play so I hope it will turn out good this time as well.
 
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I bought one of the china junk turbos off ebay for $300 a hx40 suoer drag. And compared it to a hx40 holset. Thay are identical to each other except for different names stamped on the front houseing. So I installed it on my truck and its been spooling hard for over 2 years now with no problem at all! People call them junk because they would rather keep there money in america which is completly understandable. But I want what's cheapest and works the same. So I got one juat to try. It works great. No regrets.
 

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Ran across this with a google search and will correct an error. Mr. "Kronic murder" posted a device that will not work.

The way a boost elbow works is that it creates a restriction on the turbo side, and a controlled leak (*insignificant* performance-wise) on the actuator side. His explanation is close, but will not work without the controlled leak, which requires "wire gauge" drills which are TINY. Way too small for any regular drill to grab. By the time you are set up to drill the hole you could have bought an adjustable boost elbow. Only worth it if you want wire gauge hole drilling capability- probably with a 3jaw dremel.

Aside from this little detail his method will work. But Even aside from the drills you probably will spend about the same amount as buying a $20 adjustable boost elbow off ebay though.
 
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