BIC DDP+Turbonetics 62-1= wastegate problems?

[gixxer750]

well, I've got a 5 psi-15psi adjustable wastegate actuator on my turbo, I've got the spring set low, around 5 psi. Well, when I get to 5 psi under WOT, it settles there for a second, and I can hear the dump on the DDP open. The dump stays open, and then the boost takes off.... 5-10-13-15....+ I've seen 20 psi one time.

The wastegate flap is larger than the ct, I'm wondering if it is partially blocking the dp dump tube and causing my boost creep. Any other ideas?

 

[MDCmotorsports]

Gix:
See if the flap is hitting the flange on the DDP.

 

[gixxer750]

no... its not, we cut the weld out of the dump tube with a die grinder because it was at first. But the flap is amost the same O.D. as the dump tube. It does open all the way though.

 

[jtamulis]

It sounds like the turbonetics exhaust wastegate. That's why I went with the
LIPP stainless one . I helped fix that problem back in the day, but some
still don't have it fixxed. The wastegate "rod" is warping and rusting under the
heat and stuff.

Jeff

 

[gixxer750]

Its brand new turbo and the wastegate actuator is a modded 300zx one.

 

[jtamulis]

yep, sounds about right. The Turbonetics rear exhaust housing is complete and utter
CRAP, period. The LIPP stainless one is light years better, hence why I'm using it in
my turbo line.

 

[hottscennessey]

I'm in the same boat as you gixxer.. only with a SP61GT and a cooleze DP. I've already replaced the actuator, checked clearance several times, and hit 22psi once, which was enough.

 

[jtamulis]

Dammit, why do they still use the old design. I taught ITS, and Turbonetics
how to fix that damned exhaust housing 4 YEARS ago. That shit is gonna blow
up another car (blew my 454rwhp MKIII up because of that thing, and Two of
Eric Verah's motors). Pretty much I can sell the LIPP housings because I fixxed
Brent's Turbo way back in the day when LIPP was buildling their new stainless
houseing.


Guys, listen VERY carefully. Take the turbo OFF the car, cut the old flapper
ROD out of the turbo, replace it with a 12mm bolt, reweld the flapper and
the wastegate arm, and stick it back in. OR contact me and I'll get Greg at
LIPP to get you guys the fix kits. They made those up years ago to fix the
problem you guys are having.

Jeff

 

[gixxer750]

this is possible with a turbo with 63 miles on it? The wastegate arm moves freely. I was thinking the problem was in the dp itself, because the diameter of the wastegate flap is the same size as the dump pipe inlet.

 

[aye mate]

Drive it without the DP and see what happens.

 

[LuvMySilverSupra]

gixxer, if u have a air compressor, hook it up to the waste gate inlet, and see how much pressure it needs to open the waste gate. the internal we got for dziuggy's sp61gt back in the day was supposed to be 10psi spring, but on the compressor, it didn't open till after 30psi, and we were having same problem as you.

worth a try i guess, and aye mate's idea sounds good too.

 

[jtamulis]

this is possible with a turbo with 63 miles on it? The wastegate arm moves freely. I was thinking the problem was in the dp itself, because the diameter of the wastegate flap is the same size as the dump pipe inlet.

Yes it's possibly, but realisticly only if you only drove it a few miles and then let it sit. It's pretty much junk from the start

HOWEVER it's unlikely till about 500 or so miles.

Jeff

 

[gixxer750]

turbo has only been installed for about 6 days, and I've driven it a few of those. It's done this since day 1. I pulled the actuator rod off, and the flap moves freely. I checked the actuator, and it opens at 6 psi with compressed air.

I can hear the dump tube open around 5 psi, so I know the thing is opening.

 

[jtamulis]

the "rod" and "housing" are of two different steels. The "rod" expands different
when it gets hot, causing it to stick. My wastegate worked just fine OFF the
car. But I would have problems that it wouldn't build boost, and wouldn't build
boost, so I thought my diaphram was messed up on my turbo and drove to my
wife's mom's place in Canada. When I got there I went driving late at night, and
hit the gas, in 3rd, expecting nothing and it stuck the wastegate shut and
boosted to 30psi. I was impressed to feel the car go sideways at 80MPH tho!

Jeff