Jump to content
HybridZ

Porting Wastegate hole?


240hoke

Recommended Posts

Hey guys

 

on my new turbo the puck for the wastegate housing is ~1 3/8" inches wide and the hole in the turbo is ~7/8" wide. Top-end recommended me port this out a bit to ward any boost creep etc. Any precaution I should take while doing this, or would you recommend it?

 

album_pic.php?pic_id=2629album_pic.php?pic_id=2628

 

 

Also can anybody help my with hooking up a dual port wastgate actuator using a manual boost controller, this topic is not mentioned in corky's book and i cant find anything in the archives about hooking one up

 

thanks

 

-Austin

Link to comment
Share on other sites

As a point of reference, the hole in my housing is 1 3/8". While making yours bigger would not hurt, I would not do it w/o taking some measurements first. While the difference in the diameters of the puck and the hole is .5", there is no guarantee you will have a perfect .25 overlap all the way around. You cannot count on bolting up the wastegate housing and having the puck perfectly centered over the hole. You might also have the slighest amount of movement of the shaft in the bushing.

 

You can place some grease around the hole then bolt up the housing and see how the hole aligns on the puck. That will tell you if you can make the hole bigger using the same puck. If you decide to go with a larger puck, be very careful as you do not have much room for a larger one and you want to be certain the larger puck will not have interference problems and will sit flat on the turbine housing and seal the hole when it closes.

 

While it is a PITA, I would go with it stock and see if you need it. If you do, then the hole will have left a mark on the puck for you to go by.

Link to comment
Share on other sites

I modified my Nissan wastegate and it was a major PITA as Scottie suggests. I didn't want to go through the trouble of an external wastegate and I also wanted to keep my current "Scottie" downpipe. Boring the hole was difficult according to my machinest because the metal was extremely hard. I don't remember the actual measurment, but I made the hole as large a possible while still maintaining a consistant .125 seal on the new flapper valve. I made a custom flapper valve using a stainless steel lawnmower valve. The trick was getting the proper free play in the valve so it seals properly yet does not catch on the wastegate hole. So far it holds a steady 15psi with a T04E 50 trim compressor wheel. I've yet to try 20psi. I'm sure it will have some boost creep as compared to an external wastegate.

Link to comment
Share on other sites

I enlarged the waste gate hole on my turbo using a die grider and a 0.250" diameter carbide cutter. It was easy since the housing is made of cast iron. However, I'm using an external wastegate. I would not enlarge it too much if you are going to use the stock flapper style waste gate to close off the hole. You could grind the hole out 0.020" all the way around then smooth out the sharp edges to increase exhaust flow out the hole.

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.

Guest
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...