96 5vz xcab 4x4 TACO TURBO BUILD

Not sure what you are trying to say.

Exhaust leaking out is ok (unless you are from the EPA). Atmosphere leaking in is not. All I know is an open wastegate is better for performance than a closed loop wastegate. You just have to make sure you have a good quality wastegate that won't leak if you are open. If you are closed looped, a leaky wastegate should still be fixed, but at least you aren't screwing up your O2 sensor. Why I replaced the Cx wastegate with a Tial.

Wastegate should be connected to the vacuum fitting on the turbo and only react to boost at the turbo. If you have a vacuum leak in the manifold, the turbo will continue to spin up as manifold pressure will be lower than boost pressure at the turbo itself. Its a safety thing. I don't think its a big issue when running 8 psi though. I don't know if vacuum will damage the wastegate but it def sees some vacuum, even at the turbo fitting.

 

Lol I don't know how else to say it. On my truck, open wastegate in closed loop part throttle boost=poor(er) performance. Closed wastegate in closed loop part throttle boost=very smooth and no hesitation in timing. There is NO other explanation for this. It is 100% a timing issue. I'm well aware that a wastegate that is dumped back in creates more back pressure and resistance that lowers horsepower, but this has nothing to do with that.

 

If open waste gate is an issue, you might have a leak. My CX leaked pretty bad. If the machining isn't perfect on the valve seat, it will leak which will cause your O2 to think you are too lean. The issue is (especially when at idle) you exhaust runs in pulses which would give you pulses of atmospheric air leaking into the exhaust and cause your ECU to go a bit wonkers.

When my waste gate was leaking, I would get surges and falls during idle, low to mid range pulls were a bit shitty and not smooth at all, sometimes I'd get a surge or fall randomly as I started off form a stop. Replaced the wastegate and get great response again, good idle, and quicker boost.

You may have a leaking wastegate.

 

That's the thing though... truck drives fantastic now... like better than ever. it would feel squirrelly regardless of where the vac line was hooked up if the squirrelliness was in fact due to a valve seat leak.

 

Not do to the vac line but the wastegate itself is leaking past the valve seat and into the down pipe. When the down pipe was open, you were probably sucking in air through the waste gate, into your exhaust, and screwing up your O2 sensor readings. When you close looped the wastegate, its still leaking, but now its not sucking in air from the atmosphere. But its still letting some exhaust gasses by which can slow down your turbo spool. Probably not by much

 

No, my lag is non-existent. Full boost at 2300 RPMs. It is a timing issue when the wastegate opens in closed loop and ONLY when the wastegate opens in closed loop. It no longer opens in closed loop since I attatched the line to the mani so the weird timing retard no longer exists.

 

Interesting

 

Why would there be vacuum at the turbo outlet and/or in the charge pipe? The vacuum is in the manifold, not in your charge pipe.

 

Sure there will. Anywhere you have high velocity air or fluid rushing over a smaller opening, it will create a vacuum at that opening.

 

Yup.

 

OMG I'm cmn r u..... Within the next couple weeks I will be among the few and proud.

 

Lol yeah dude it definetely gives you a chubby every time some guy in a v8 whatever thinks you're going to be slow and you end up waving at him in your rear view mirror... and you're probably going to be rockin at least 8 psi before I do. That is going to be rediculous haha

 

You'll never see 20 inHg worth of vacuum in the charge pipe like you'd see at the manifold during closed throttle. Hook your boost/vacuum gauge to the charge pipe and have a look.

 

Boost gauge should be hooked up to your manifold, waste gate should be hooked up at the Turbo. Sure you can do it any way you like, that that's what's recommended

 

It's also reccomended to tie your WG dump back into the exhaust.
I can assure you guys that there are WAY more people running their WG from the manifold than there are guys running BG's from their charge pipes. My truck runs way better with the WG on the mani, so that's how I choose to have it... end of story.

 

Is there anything that I need to use threadlock on?

 

Anything you don't plan on taking off. I bought a second nut for my V-band clamps to use as lock nut. I used high temp lock tight on exhaust head bolts IIRC.

 

Damn, that locktite is $25. Once again the $$$ fly away. Worth it though for some ultra secure headers.......

 

Yes it is very worth it... unless you feel like tightening down all the nuts every few months like I do (ugh)

 

Oh man, no thanks......Wondering if I should put it on the vbands too, or could that end up being dangerous if they need re tightened?