Exhaust leak at flapper rod?

[FastB]

Been noticing black exhaust carbon and water condensation on my oil filter and a spot of clear water on the garage floor at start up. Watched the motor idle and noticed a little puff of smoke coming from the pivot rod in the housing for the flapper...which I'm assuming where my problem might be. Has anyone heard of this?...I'm not aware of any seals there.
Also, the turbo spools slow..crazy boost lag...I know its a good sized turbo but this lag is exessive imho. I do have a precision housing...mods are in sig.



here is a pic of my engine bay...it's coming from where the wastegate rod connects to the housing...flapper rod?





this isn't mine but it's a pic of where I'm seeing the puff of smoke coming from:

 

[DSEROVY]

Mine does the same thing - has since the downpipe was new. It's a fairly loose fit for the shaft to go through- no seal. Mine is a G-Body pipe - I've never worried about it.

As far as your boost lag, I would pop off your downpipe to make sure your puck is sealing the wastegate hole - you should be able to see a complete seal around the hole.

 

[FastB]

Thanks I'll check it out.

I've had a couple turbo cars and the lag on this car is crazy...you can floor it and count to 2 or 3 before the boost comes on...when it does come on it usually lights the tires up so the power is there just slow..LOL. Maybe it's just the way these cars are...I've only had this one for 6 months and still learning it's kwirks.

 

[bison]

The stock elbow has a slight leak in this area. Some aftermarket pipes have too little clearance and the swing valve shaft will seize in the bore. This will cause severe over boost and engine failure. Ive seen it happen. Good aftermarket pipes have at least enough clearance to prevent this from happening. Some have more than others. Id rather have it too loose than too tight. Not too many instances in life where you will ever hear me say that though. What is the converter stall speed at zero boost/zero vacuum?

 

[22lbChevelle]

Great point Bison.

Before I swapped back to an internal wastegate, I had an old external setup and the wastegate would get stuck closed if I didnt drive the car for a while. Next time I went out the boost would go straight to 30psi and luckily I always noticed it was heading to the moon and was able to let off. Then I'd have to remove the wastegate, disassemble, and work the piston loose.

Wastegate sticking closed is real, and real bad. So I agree that a bit morre clearance is better. The leak is after the stock O2 and the turbo so it will not cause lean readings or slow spool.

 

[Jerryl]

The stock elbow has a slight leak in this area. Some aftermarket pipes have too little clearance and the swing valve shaft will seize in the bore. This will cause severe over boost and engine failure. Ive seen it happen. Good aftermarket pipes have at least enough clearance to prevent this from happening. Some have more than others. Id rather have it too loose than too tight. Not too many instances in life where you will ever hear me say that though. What is the converter stall speed at zero boost/zero vacuum?

Most prefer a tighter fit with the P-Trim.

 

[FastB]

So, I need to take the pipe off to check to see if it's stuck or not? Other than the puffs of smoke out of it and the boost lag (which may or may not be the same issue) it's not having any other problems...boost jumps to 26# like it's supposed to.

 

[Jerryl]

So, I need to take the pipe off to check to see if it's stuck or not? Other than the puffs of smoke out of it and the boost lag (which may or may not be the same issue) it's not having any other problems...boost jumps to 26# like it's supposed to.

You can remove the arm and make sure the flapper is moving freely.
No need to remove the pipe.

Now, if you have boost lag (Definition of "lag" varies greatly), you may have;
1-A puck that is not sealing
2-Converter that is too tight/turbo too big
3-Tuning issue
4-Combination of all the above.

That 70 turbo needs a GREAT converter to reduce lag on a 231CI motor.

 

[FastB]

I'm leaning towards turbo is a tad big for my setup. I have a 9.5" 3200-3500 vigilante converter. It makes a lot of power just comes on slow unless brake boost.
If my Flapper moves freely but has a leak is it fix able or should I even be worried about it. Ive only owned this car for about 10 months and haven't driven it much so I'm still learning what's normal for these cars.