Jump to content

Possible problem with turbo


Recommended Posts

I have been trying to figure out a problem with a turbcharger giving too much boost. Even with the wastegate puck opened all the way gives this L28 20+psi. At first I thought maybe the bleed hole was too small, but it is 7/8", should be big enough to bleed a fair bit of exhaust pressure?...


Now I am thinking maybe the turbo itself is a problem, it is a hybrid t3/t4 however I have no idea what the specs are on it. The compressor housing is quite large and has a 3" inlet and 2" outlet, however the exhaust outlet is only 2" Is it possible that the compressor housing is far too big for the turbine housing? A small exhaust wheel would get the compressor going very quickly (which is does..) but once the engine pushes out the exhaust it chokes through a small housing causing a pressure build up inside the engine and therefore the 20+psi right away...



Any thoughts on my "theory"??

Link to comment
Share on other sites

I remember someone having a similar boost creep problem with a similar setup to yours. They were able to port the wastegate hole to allow more exhaust gas to bypass the turbine. Focus on the short side radius if you plan to try this. Maybe you can enlarge the hole and use a larger gate too.


Check out Jason's Z31



Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...