Tuesday me and the local 7 guys are going to be instaling my new RB catback and such on my 87 TII, and we're going to be porting the wastegate in the process. We have the tools, all we really need is maybe some diagrams or anything that you would think is helpful. I did search for threads trying to find the answer however i was unable to find what i was looking for.

Any help is apreciated. Thanks a bunch!

~Erik

 

Its really not anything you need a diagram for. When you take off the turbo, you will see 6 13mm bolts holding the 2 halves of the turbo together. You will probably want to remove the oil and coolant lines 1st. Then remove these bolts,the wastegate actuator rod, and then remove the exhaust housing from the center section. From there it is pretty self explanitory. YOu will see the wastegate flapper, and the hole underneath it. POrt the hole within about 5 mm of the flapper. I would suggest getting a larger flapper welded on so that you can port the hole even larger. Just make sure it still opens and closed without getting hung up on anything.

 

You removed your hotside of the turbo .

Hell I just undid the 2 14 mm bolts that held the cover plate on.
Disconnected the wastegate actuator- traced the flapper- and then ground out till I was like 1/16th " to hitting the line, so that it could close and seal still.

Uh yeah I stuffed the turbine, then used a shopvac/air compressor to clean it out REALLY well.

 

I suppose that would work just as well, I just didnt want to take the chance of getting metal shavings inside the turbo.

 

I would suggest a honda exhaust valve as a replacement flapper. Just grind it out until it's about the size of your thumb. There is a thread for this if you want to do a search.

 

I have no idea why people keep mentioning Honda exhaust valves. An exhaust valve from any other manufacturer will do just fine.

Personally I would not even bother porting the wastegate unless you have the necessary tools and parts to put a bigger flapper on. Otherwise you're only doing a half-job that you'll probably regret later when you still get boost creep.

Getting the wastegate ported and having a bigger flap fitted at the same time is something a turbo workshop will do pretty cheaply. I'd expect to pay well under US$100.

 

http://fc3spro.com/TECH/HOWTO/ZWG/zwg.html

http://fc3spro.com/TECH/HOWTO/KWG/kwg.html


-Ted