350 mag Exhaust

[ShakerTransAm]

Looks like my stock mercruiser manifolds are starting to rot out. What is a good replacement? Don't need anything spectacular, I'm ok with running stock again. Has anyone used the GLM manifolds? Sierra? Thanks

[gold-n-rod]

I have a pair off a 305.

Does anyone know if the Mag/non-Mag manifolds are the same?

They can be shipped, I'm sure.

[duckhunter]

I'm a fan of the GLM aluminum manifolds and risers. Supposedly they add a couple of horsepower due to the cast-in runners. Maybe so, but the real selling point is ease of installation! Wrestling the old cast iron anchors out was a bear, but dropping in the new GLMs was a breeze. And besides, who doesn't want to lose 80# out of their stern?

Availability might be a pain. It's been a few years since I bought them, but they were hard to find at the time. Price is maybe $200 more than GLM (Sierra, etc) cast iron units. Part of that you make up in shipping, and the rest from hernia avoidance.

[Ghost]

FWIW, I'm a big fan of the Stainless Marine manifolds. I suspect they are actually close to cost-effective, despite paying the extra up-front.

[duckhunter]

FWIW, I'm a big fan of the Stainless Marine manifolds. I suspect they are actually close to cost-effective, despite paying the extra up-front.

Good point, especially in a boat that will (or even might) see salt.