Exhaust Flexi's Explained
What is an Exhaust Flexi?
An Exhaust Flexi is constructed of three layers, the inside has a interlocking inner, a middle ribbed section (similar to a Exhaust Bellow) that re-enforces the inner layer, and a outer woven stainless steel wire exterior, its purpose is to act as a point of movement in an exhaust. (these can also be used for external wastegate pipes).
They reduce the weight and vibration being transferred back up through your headers or turbo setup, this weight and vibration is created from the length of exhaust systems. If your exhaust is well mounted and supported then you will have less chance of issues. Without an Exhaust Flexi the chances will increase of bolts, studs and nuts loosening, and the cracking of exhausts, downpipes, headers & turbo manifolds.
Can an Exhaust Flexi be repaired?
One common issue of an Exhaust Flexi is that if fitted to a vehicle that has poor ground clearance over time they scrape and can quickly wear through creating an exhaust leak.
Once this occurs they cannot be repaired because of the thin material and stainless steel wire exterior, these materials are too thin to weld successfully and if damaged they will need to be replaced.
x4 Helpful tips to install an Exhaust Flexi
To eliminate the issue of a Exhaust Flexi deteriorating from scraping on the road try mounting it up near the downpipe more on a vertical than the typical horizontal method. Another method to stop it scraping on the road is to mount it up above the lowest point of your exhaust tube.
Do not use the inner wire mesh type flexi, these collapse due to high pressures from exhaust flow and the heat that is created from turbo vehicles. If your flexi collapses it can quickly cause major damage to your turbo charger and or engine
If you are having trouble achieving a consistent weld around the card sleeve of the flexi try running a quick weld around the ends first to fuse all the layers together. This will allow for a more solid base for welding instead of trying to fuse all the layers together and weld to the tube at the same time.
Mount the flexi up near the front of the exhaust, generally around 500-1000mm from your engine. We prefer to mount the flexi joint just after any bracing. Ultimately you want to keep your downpipe section common to the engine then use the flexi so the exhaust can move freely after any solid bracing.