[Steelmesh]

After installing the ZZP downpipe / mid-pipe I noted some really wacky fueling and reduce mpg. I found the vband clamp was completely loose (spinning with fingers).

I lifted the car and loosened the cat flange bolts and the muffler bolts. With the V-band loose enough to still let the pipe shift a little, I shook down the pipes to help it settle a little. I then snugged the V-band not to full torque, then torqued the flanges. I then tightened the V-band to 125 in-lbs (OEM 115 in-lbs). I started the engine and let it idle for a bit, then was able to turn the bolt more to reach 125 in-lbs.

After every drive, I check the torque, it has dropped and requires about 15 degrees of turning to reach torque again. After a few times, I tried 145 in-lbs, this does not help.

I will get a new V-band clamp and see if this solves it.

Does anyone else have experience with the 1.4T v-band clamp?

 

[obermd]

Sounds to me like you damaged the threads somewhere.

 

[Steelmesh]

Sounds to me like you damaged the threads somewhere.

Not sure how I would have besides over-torquing.

eautorepair.net has very limited details about how to properly deploy the v-band clamp. They show a 1950's bw cartoon image of the clock angle of the v-band bolt and say hand tighten it to torque the exhaust system, then come back and torque it to 115 in-lbs. That's it.

I see some tips googling, like using dry lube and even silicone sealer on the band, all for the purpose of helping the components move into place. Several also say drill the bolt head to wire it to prevent loosening.

 

[Steelmesh]

Following up here: I only had to torque it a couple more times after this last post. It is maintaining 125 ft-lbs and holding. I assume everything must have nestled. If it happens again, I am going to test out a 3.5" aftermarket clamp.

 

[Tmiller39]

Hey which one is the vclamp?on my turbo on the front right below the radiator my clamp isn't even connected it's just dangling.do you happen to know what size it is? I have a 13 Cruze lt turbo