Hooker Blackheart 1967-72 C10 Truck LS/LT Swap System Info Thread

[derotoreut]

Originally Posted by toddoky

Exhaust bellows are typical only used on hot-end exhaust assemblies where necessary to allow for material expansion between two rigid components located in close proximity to each other (i.e. the exhaust manifold to turbo connections on the back of the Duramax Diesel engines), or to provide a means to deal with the slight mis-alignment of components that is expected to exceed a specific production tolerance. Exhaust system H and Y pipes themselves don't present either of these issues (especially ones used in systems without catalytic converters) and therefore don't require the use of bellows, as long as the fixtures for the components are designed correctly and their manufacturing is carried out as intended.

So I'm assuming any flex generated in the system by engine torque is insignificant in this application. And without catalytic converters there is no concern of excessive heat that may cause thermal expansion issues. Thank you for taking the time to explain this.

[toddoky]

Originally Posted by derotoreut

So I'm assuming any flex generated in the system by engine torque is insignificant in this application. And without catalytic converters there is no concern of excessive heat that may cause thermal expansion issues. Thank you for taking the time to explain this.

Yes, your assumption would be correct. You can use exhaust systems designs of OE manufacturers as an example as to whether bellows are required from an engineering standpoint. You will be hard pressed to find one used in any OE exhaust system other than at a critical or highly constrained hot-end component connection. They don't spend a nickle or dime they don't have to.