EVO III Boost Creep Problem Solved!

[Tarantula]

I did some more porting on the Evo 16G. I gasket matched the wastegate area and smothed out all the steps in that area. I removed a huge step that was on the divider itself. I did nothing to the wastegate hole under the flapper except mirror polish. I also mirror polished the wastgate area from below the flapper on up to permit the smoothest flow. Touching the area feels like its wet with oil. Can almost see my reflexion as well. Did all this with a Dremel and a carbide bit. Sanding drums, buffing wheels and Mothers mag and aluminum polish. I'll see if any of this helps. Probably install by next week.

 

[Tarantula]

another angle

 

[njshift]

http://www.usionline.net/122/contacts.htm

contact info

 

[Maximuscr31]

jsut to let everyone know. That method didnt work for me I have alot of creep still. I ported it out as it says plus im running a external dump. I can go about 70% throttle now without creep. I have ran it off the manifold to the wastegate bypassing the mbc. I have worse control then and it creeps more. I have tried tieing the flapper open and i still build boost and if it is a higher gear then it still will creep to 20+psi. Tonight with all this done I am still htting 22-28psi in the gears.The worst part is it creeps worse in the lower gears than the higher ones.ITs really weird. ANyone have a idea on how to fix this other than external wastegate let me know. Thanks

 

[ShapeGSX]

External dumps with internal wastegates make creep worse. The reason is that it increases the turbine efficiency by lowering the post-turbine pressure.

 

[njshift]

shape is your tubular O2 housing still holding up as desired?

 

[ShapeGSX]

Originally posted by njshift
shape is your tubular O2 housing still holding up as desired?

Seems to be.

 

[Tarantula]

Wanted to give an update as to how this job came out. My Evo III 16G has absolutely no boost creep straight to redline!!!! Not even spikes. From the moment I hit WOT to redline needle jumps straight to 15 psi and hit the brakes right dead on 15psi, without going over even a little. I have also tapped the turbo to harvest the T-25 boost source. When I hooked straight from boost source to Wastegate, it don't boost over 9-10psi. I thought the Evo III 16G was suppose to have a stiffer spring and higher boost??? I attached a pic of my custom boost source adapted to the compressor cover.

 

[GPTourer]

I ordered my EVO3 from SBR UN-ported but with the flapper mod, my controller is set up from the wastegate to the BOV. I have a 3" o2 eliminator DP I got from Extreme Turbo. I can hold 19psi to redline with no creep.

 

[njshift]

the big flapper blows open at higher psi..

 

[siceclipse]

sorry for bringing this back but Tarantula, how does that new boost source make you not creep? im not stupid and im not starting S#it i was just wondering if you could elaborate more.

 

[Tarantula]

sorry for bringing this back but Tarantula, how does that new boost source make you not creep? im not stupid and im not starting S#it i was just wondering if you could elaborate more.

I think you misunderstood what I wrote. I was merely stating that I made a boost source just like the T-25 since the Evo 16G does not have one. Normally when people by the 2G kit, the lower intercooler pipe after the J pipe has a boost tap. I just made it easier and closer to the turbo.
When I stated the boost not going 9-10psi, I was pointing out that the Wastegate that came with the Evo III 16G does not have a higher spring pressure than 9-10psi. It was said that these turbos came with a stiffer spring pressure and in my case it didn't. I really think that was just a myth with the higher spring pressure. Also my point was that I did not get boost creep at 15psi or 9-10psi.
Currently I have my boost set to 17-18psi and still no boost creep. to this day. I have run pure free exhaust(Test pipe) with no creep issues.

 

[siceclipse]

Ok that clears everything up, and thanks for the pics ive been using them as models to port my own stuff.