91 Q45 Exhaust Manifolds

[campbelljj]

I know the Q uses an integrated exhaust/catalytic manifold from the head. Typically how long do these manifold cats last? My car has 86k. Are there any aftermarket headers or alternatives anyone has used? Can the catalytic converters be removed?

[maxnix]

They can be cored out, but there is no gain.

They will last the life of the engine, typically 350K+ if well maintained.

For custom headers, read rswicki's posts.
Modified by maxnix at 1:18 PM 2/10/2007

[Q45tech]

Never seen or heard of a 90-93 manifold failing unless they get melted from a fuel injector leak or very lean conditions for years.

Robust is a mild word.

All JDM engines come in with unusable manifolds so every engine we've swapped got the old oem manifolds reinstalled..................they last 300k+.