92Landyacht
OBS Enthusiast
OK, here's the deal. My 1992 Airstream Land Yacht motorhome (P32 chassis and a 454 engine) is having an issue. A couple of weeks ago I noticed a strange sound coming from the engine. It's not a hard knock but more of a PFFFFT.. PFFFFT sound. The sound gets louder when the engine is under load and gets faster with engine speed. At idle and deceleration it's not very audible if at all. Thinking it's an exhaust manifold that either cracked or a stud that's failed along with the gasket. Seems to get a little quieter after it's been run and it's louder on some days than others. Really hoping it's not a rod bearing.
Assuming it's an exhaust problem, what would you guys recommend. If the manifold is bad, would you guys be thinking of some long tube headers or replace the manifold with a stock replacement. I've looked in the Banks Power Plus systems that includes the complete exhaust system and a fresh air intake. It a lot of work to install but if the manifold has to come off anyways, it would be the best time to do it.
Assuming it's an exhaust problem, what would you guys recommend. If the manifold is bad, would you guys be thinking of some long tube headers or replace the manifold with a stock replacement. I've looked in the Banks Power Plus systems that includes the complete exhaust system and a fresh air intake. It a lot of work to install but if the manifold has to come off anyways, it would be the best time to do it.