[65 Lamnas]

Originally Posted by ZeGermanHam

There is some variation on the internal design of the Dynomax Superturbos dependent on the case size. I have the smaller 16" 17629 model, and it has a totally different design, without the flow directors that most people think of when discussing superturbo mufflers. They just have the dimples in the outer case (see photo attached).

Although I have Dynomax superturbos currently installed on my car, I think the Summit Racing turbo muffler is a better choice. I also own a pair of those (not installed), and they are better constructed (in the US), cheaper, and don't neck down to 2-1/4" internally like the Dynomax Superturbos do.

Attachment 625872

Resurrecting this partly because I'm also in the hunt for some turbo mufflers for the '65 Lamnas.

Unfortunately, I don't want the reduction in diameter on the internals either...but the Summit Racing ones you mention actually DO neck down...at least for the 3" ones...

Summit Racing™ Turbo Mufflers
Made with free-flowing large diameter tubing—as much as 20 percent more than some competitors—Summit Racing™ Turbo mufflers offer you deep performance tone without being too loud. They feature 2.5 in. internal cores with 360 degree perforations, roll-seamed end caps, 100 percent aluminized construction, and seam locked cores that prevent the center baffles from twisting out. Installation is a breeze with their fully reversible design. The mufflers are available in a variety of inlet/outlet diameters and locations. Order the model that best fits your application.

The nice thing about the Dynomax Super Turbos, P/N 17770, is that they maintained the 3" on the inside, but I think they've been long discontinued...

[GtoFM]

Originally Posted by 65 Lamnas

Resurrecting this partly because I'm also in the hunt for some turbo mufflers for the '65 Lamnas.

Summit Racing™ Turbo Mufflers
Made with free-flowing large diameter tubing—as much as 20 percent more than some competitors—Summit Racing™ Turbo mufflers offer you deep performance tone without being too loud. They feature 2.5 in. internal cores with 360 degree perforations, roll-seamed end caps, 100 percent aluminized construction, and seam locked cores that prevent the center baffles from twisting out. Installation is a breeze with their fully reversible design. The mufflers are available in a variety of inlet/outlet diameters and locations. Order the model that best fits your application.

The nice thing about the Dynomax Super Turbos, P/N 17770, is that they maintained the 3" on the inside, but I think they've been long discontinued...

FWIW Summit uses this same description on all of their USA made turbo mufflers, even the 2 1/4”.

First, I’m not an engineer, but retired from the HVAC trade. A sheet metal journeyman told me to increase airflow velocity, the duct size would be decreased then oversized similar to a thumb restricting water from a garden hose. Not sure if this applies to mufflers or crimping down is a production cost savings.?.

[ZeGermanHam]

Originally Posted by 65 Lamnas

Resurrecting this partly because I'm also in the hunt for some turbo mufflers for the '65 Lamnas.

Unfortunately, I don't want the reduction in diameter on the internals either...but the Summit Racing ones you mention actually DO neck down...at least for the 3" ones...

Yeah, I was referring to the 2.5" units that do not neck down internally.