Question on Exhaust Manifold

[niky]

It's not advisable to change exhaust manifolds on diesel engines as this adversely affects torque and can have a nasty effect on your emissions.

For NA gas engines, equal length headers (as opposed to stock log manifolds) are best.

For turbo engines, either gas or diesel, stock log manifolds are designed very short to provide lag free turbo response, but aftermarket equal length short headers are available for most common turbo gas engines to provide smoother light up and more power. I don't know if any are available for turbodiesels, but I doubt it.

[jeanpierre]

It's not advisable to change exhaust manifolds on diesel engines as this adversely affects torque and can have a nasty effect on your emissions.

For NA gas engines, equal length headers (as opposed to stock log manifolds) are best.

For turbo engines, either gas or diesel, stock log manifolds are designed very short to provide lag free turbo response, but aftermarket equal length short headers are available for most common turbo gas engines to provide smoother light up and more power. I don't know if any are available for turbodiesels, but I doubt it.

niky thanks sa info.