No cast iron? Are GLM exhaust components aluminum (i.e., manfolds, risers)?

[Philster]

I know the notorious GLM brand. Generally considered cheap, but some folks find the discount price worth it when they take time to check mating surfaces, etc. However, I never gave any thought to it, but being a salt-water boater, are GLM exhausts aluminum?

I never see a reference to them being cast iron or offering a cast iron version.

I almost consider aluminum to be out of scope for salt water user. So, what gives here? Are GLM exhaust pieces aluminum, and -- if so -- is aluminum recommended against in salt water applications (e.g., on a big block 502 Merc, I/O, raw sea water cooling).

 

[Bondo]

Re: No cast iron? Are GLM exhaust components aluminum (i.e., manfolds, risers)?

I never see a reference to them being cast iron or offering a cast iron version.

Ayuh,... I believe they do Both, iron, 'n aluminum...