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Flowmaster

Flowmaster 70 Series Big Block II Mufflers

4.69 out of 5 stars 124 Customer Reviews

These 70 Series Big Block II mufflers are designed around a large case for maximum volume and efficiency. They're 2 in. narrower than the original Big Block muffler, making them easier to install into tight areas. Other features include a mild, mellow exhaust tone and a resonant tuning chamber for reduced interior sound levels.

Showing In Stock Items. Show All 7 Items.

Results 1 - 7 of 7

Flowmaster 70 Series Big Block II Steel 3 Inch Muffler 53071

Flowmaster 70 Series Big Block II Steel 3 Inch Muffler 53071

Flowmaster 70 Series Big Block II Steel 3 Inch Muffler 53071

Muffler, Big Block II 70 Series, 3 in. Inlet/3 in. Outlet, Steel, Black, Each

Part Number: FLO-53071

4.53 out of 5 stars ( 19 )

Estimated Ship Date: Monday 11/24/2025

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Estimated Ship Date: Monday 11/24/2025

Flowmaster 70 Series Big Block II Steel 2.25 Inch Muffler 524703

Flowmaster 70 Series Big Block II Steel 2.25 Inch Muffler 524703

Flowmaster 70 Series Big Block II Steel 2.25 Inch Muffler 524703

Muffler, Big Block II 70 Series, Dual 2 1/4 in. Inlet/3 in. Outlet, Steel, Black, Each

Part Number: FLO-524703

4.54 out of 5 stars ( 13 )

Estimated Ship Date: Monday 11/24/2025

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Estimated Ship Date: Monday 11/24/2025

Flowmaster 70 Series Big Block II Steel 2.5 Inch Muffler 52571

Flowmaster 70 Series Big Block II Steel 2.5 Inch Muffler 52571

Flowmaster 70 Series Big Block II Steel 2.5 Inch Muffler 52571

Muffler, Big Block II 70 Series, 2 1/2 in. Inlet/2 1/2 in. Outlet, Steel, Black, Each

Part Number: FLO-52571

4.89 out of 5 stars ( 9 )

Estimated Ship Date: Monday 11/24/2025

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Estimated Ship Date: Monday 11/24/2025

Flowmaster 70 Series Big Block II 409 Stainless Steel 3 Inch Muffler 853072

Flowmaster 70 Series Big Block II 409 Stainless Steel 3 Inch Muffler 853072

Flowmaster 70 Series Big Block II 409 Stainless Steel 3 Inch Muffler 853072

Muffler, 70 Series Big Block II, Oval, Stainless, 3 in. Center Inlet, 3 in. Offset Outlet, 22 in. Case Length

Part Number: FLO-853072

4.67 out of 5 stars ( 27 )

Estimated Ship Date: Monday 11/24/2025

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Estimated Ship Date: Monday 11/24/2025

Flowmaster 70 Series Big Block II Steel 2.5 Inch Muffler 52573

Flowmaster 70 Series Big Block II Steel 2.5 Inch Muffler 52573

Flowmaster 70 Series Big Block II Steel 2.5 Inch Muffler 52573

Muffler, Big Block II 70 Series, 2 1/2 in. Inlet/2 1/2 in. Outlet, Steel, Black, Each

Part Number: FLO-52573

4.83 out of 5 stars ( 6 )

Estimated Ship Date: Monday 11/24/2025

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Estimated Ship Date: Monday 11/24/2025

Flowmaster 70 Series Big Block II Steel 2.5 Inch Muffler 52572

Flowmaster 70 Series Big Block II Steel 2.5 Inch Muffler 52572

Flowmaster 70 Series Big Block II Steel 2.5 Inch Muffler 52572

Muffler, Big Block II 70 Series, 2 1/2 in. Inlet/2 1/2 in. Outlet, Steel, Black, Steel, Each

Part Number: FLO-52572

5.0 out of 5 stars ( 3 )

Estimated Ship Date: Monday 11/24/2025

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Estimated Ship Date: Monday 11/24/2025

Flowmaster 70 Series Big Block II Steel 3 Inch Muffler 53072

Flowmaster 70 Series Big Block II Steel 3 Inch Muffler 53072

Flowmaster 70 Series Big Block II Steel 3 Inch Muffler 53072

Muffler, Big Block II 70 Series, 3 in. Inlet/3 in. Outlet, Steel, Black, Each

Part Number: FLO-53072

5.0 out of 5 stars ( 3 )

Estimated Ship Date: Monday 11/24/2025

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Estimated Ship Date: Monday 11/24/2025

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