I got a 87TII with a new engine, full race beat exhaust and the rest of the works! Prob is i got a stage 3 turbo upgrade on the stock turbo. The wastegate is the crappy litte s4 style but it is ported, which for some reason wasnt done when the turbo was upgraded. I ported it myself and got all the sides about to the edge of the wastegate door. It still wants to boost creep though! gets up to about 12psi with no boost controller. Is there any thing else i can do? Port more maybe? get a bigger wastegate door? Possible somthing else causing this? Thanks for any help!

 

You can weld on a new wastegate flapper then port it bigger. I will see if I can dig up a thread on it.

 

umm where did you get this from and what does stage 3 mean...... you cant be talking about a bnr cuz im pretty damn sure brian would nto build a stage three and leave a stcok wg non-ported.... wherever you got t someone took the rear section off.

 

i really don't hear any of these stages stuff except in games....
but last time i checked stage 3 should get u up to 300 rwhp (something like the TD-06)... now running 12 psi? thats a little low for a "stage 3"

anyhow, i think the boost controller would help you alot, even a manual one is good, just to be on the safe side for both the turbo and the engine.....

 

Definitely pull that turbo again and take it to someone who can weld on a larger flapper for you. People have used heavy duty washers just welded onto the stock flapper--to allow for a larger diameter port.

If you for some reason can't do this, then port the WG to about a mm. beyond the edge of the flapper, and then use your drill bit at an angle to open the port up more on the inside, like this-----> / \ Make sense?

Also, you can remove some material from the turbo's 'back-plate' to allow the WG-door to open up a little more. The backplate is the thick steel piece you had to remove to even see the WG. Hold it up to where it would be bolted on, and then gently open and close the WG door--making sure to carefully observe where the door would hit the plate. Then simply begin grinding into the plate, go as far as you can without sacrificing it's durability.

 

Depending on what size ports and turbo, on some even the largest stock wastegate port job will be insufficient. On my half bridgeport block I cannot even use the BNR stage4 due to wastegate inadequacy. With your turbo it sounds like a bad port job (no offense)

 

Its the biggest compressor you can get on the stock turbo! Its also had the turbine housing ported and a larger turbine put in. My frind got it from someone off ebay i think! Everything looked great on the turbo, i was actually very shocked the wastegate was not touched. I will pull it back off again and port more and use the idea of porting the inside more / \ and see about a bigger flapper put on. Thanks for the help guys!

 

Does your engine have stock ports?

If the Wastegate modding does not work your going to have to restrict the intake or exhaust to control boost.

James