Swapping 6.1 into Duster, What manifolds? (NO TTI)

The short answer is the ONLY CONFIRMED factory exhaust manifolds that will fit into an A-Body are Jeep 5.7L exhaust manifolds from a 2005, and these require a bit of grinding.

The 5.7L 2003-2008 have a square exhaust port while your 6.1L Hemi has a D-Port design. They will still bolt up but needless to say you'll have significant exhaust restriction.

Some people will say that 2006-2010 Jeep 6.1L SRT-8 Manifolds will fit, THEY WILL NOT. They do fit those with aftermarket K-members but will hit the steering column on stock K-member A-bodies.

Since 2009, chrysler redesigned the 5.7L head (known as the Eagle head) these heads use the same D-Port configuration as the 6.1L Head. FYI, the Eagle heads allegedly flow nearly as much as the 6.1L Head.

Since the Eagle head has the same exhaust port a 2009 and later 5.7L exhaust manifold might be the best bet for decent flow.

The problem is I can't find any confirmation of ANY 2009 and later 5.7L exhaust manifolds actually being used.

So best of luck, and if you actually do use a 2009 and later manifold please tell us about it. And remember pictures or it didn't happen. ;)

Regards,

Joe Dokes