I called Flowmaster about a year ago concerning a recommendation for the 6BTA Cummins in our trucks. At that time I was told that they had no muffler that would flow the volume of exhaust that the Cummins produced. They flat out told me not to use one of their mufflers.
The 6BTA Cummins flows from around 1300 to over 1500 CFM of exhaust depending on power level. A modified engine would exceed these numbers. There a quite a few mid size truck mufflers that will handle this flow. Most heavy duty muffler catalogs have charts that will give the specifications regarding flow at given back pressure.
I have selected a 4" straight thru muffler from the Donaldson catalog for my truck. I don't have the info at hand right now but it is a muffler used on several mid range trucks.
Some of the TDR advertisers offer mufflers in the 4" size and they would be able to offer you one that works. But after what I was told by Flowmaster I would not install one of theirs on my truck.
Hope this helps!
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92 D250 Auto Trans-Currently stock except for TCI special torque convertor. Now adding 16cm turbo housing, complete 4" exhaust, tachometer, pyrometer, and transmission temperature gauge. Injectors in the near future.
Also have 1984 Volvo D260 with inline 6 diesel made by Volkswagen.
The 6BTA Cummins flows from around 1300 to over 1500 CFM of exhaust depending on power level. A modified engine would exceed these numbers. There a quite a few mid size truck mufflers that will handle this flow. Most heavy duty muffler catalogs have charts that will give the specifications regarding flow at given back pressure.
I have selected a 4" straight thru muffler from the Donaldson catalog for my truck. I don't have the info at hand right now but it is a muffler used on several mid range trucks.
Some of the TDR advertisers offer mufflers in the 4" size and they would be able to offer you one that works. But after what I was told by Flowmaster I would not install one of theirs on my truck.
Hope this helps!
------------------
92 D250 Auto Trans-Currently stock except for TCI special torque convertor. Now adding 16cm turbo housing, complete 4" exhaust, tachometer, pyrometer, and transmission temperature gauge. Injectors in the near future.
Also have 1984 Volvo D260 with inline 6 diesel made by Volkswagen.