Originally Posted by ISMSOLUTIONS

There is flex in the system. We have retained the rubber mounts and allowed for system torquing with the use of flanges for all of the coupled joints.

We have also verified that there is no binding in the system - unlike most all of the other systems - which then require flex joints. I have noticed with most all of the of the clamped systems, that there is a lot of binding that occurs - primarily because exact fitment cannot be guaranteed with slip fit systems - hence the use of clamps. This system is designed to be an exact fitment - no clamps at all - all flanged.

There should be no issues with cracking at all. I have been running this system on my car for thousands of miles already, with headers as well for many miles with zero issues - the test car has may miles too.

Rick

Originally Posted by DaveB

Nissan puts flex sections in the stock exhaust for a reason.....to reduce NVH. I know the FI system doesn't use flex sections nor does Borla, Stillen, and most others. I think HKS is the only one that was smart enough to incorporate flex sections into their design. You may want to consider having a shop install some 2.5" flex sections into the y-pipe while you're getting the other work done.

Originally Posted by ISMSOLUTIONS

flex joints are used to relieve binding in an exhaust system - it allows a certain amount of travel for the exhaust as to not break headers/manifolds or CATS, etc, that are in a fixed installation.

Most all aftermarket systems are made far more stout than a factory system, thereby not requiring flex joints, as long as the jigs are made properly and to tolerance, there will be no binding in the system and the rubber mounts will provide the needed flexibility under general driving conditions as heat expands the system and tolerances get even closer.

Originally Posted by ISMSOLUTIONS

Nissan uses flex joints as their exhaust system is made to Zero tolerance specifications. Therefore flex joints are needed to allow some play in the system, otherwise they would be replacing manifolds and CATS due to the stress relief need, for expansion due to excessive heat, over time.

Originally Posted by DaveB

The purpose of the flex sections is to reduce NVH (primarily vibration and harshness) and to let the exhaust move freely instead of torquing the exhaust manifolds and cats. The flex section removes vibration by letting the engine move more freely from the exhaust. The flex sections along with the exhaust hangers and engine mounts dissipate vibration. When you remove the flex sections, you'll get more vibration. It's really that simple. I've installed numerous exhausts on my last three car. I quickly learned the value of the flex sections and I should have known better prior to buying the Borla system, but I was too dumb and believed what I read on this site from those saying it didn't cause any additional NVH. It was quite obvious after installing the Borla TD that it was creating a lot of vibration. You could literally see the pipes vibrating at idle and you could feel heavy vibration through the muffler. Under load, the increased vibration was pretty apparent. In a 350Z, it would be fairly acceptable, in a G35 is seemed a bit too much.

Originally Posted by KapVu

what's the difference between the polished and the stainless steel? I look a pictures and it looks like on both, mufflers and tips are polished on either set. Is the polished set polished all the way through (x-pipe, etc.) and stainless steel is only mufflers and tips polished? Thanks.