The 70 Series "Big Block II" uses a large case for increased volume and added sound reduction that will still fit many applications that our 50 series "Big Block/HD" muffler won't fit. It utilizes Flowmaster's patented "Delta Flow" technology for maximum efficiency and reduction of interior resonance. Use on high performance street cars, trucks, SUV's, RVs and tow vehicles. Constructed of 16 gauge aluminized steel and fully mig-welded for maximum durability.
Price: $130.00 Pros: Nice classy rumble down low, good low end torque (when combined with Kolak exhaust), very little to no drone Cons: None unless you don't want a quiet muffler. Recommended? Yes
Comments: I really like this muffler. I got it with my 3" Kolak exhaust for my 5.9. I love the deep sound. It was much quieter than the Thrush I had on before and while it took some getting used to, I really like it. It sounds especially awesome at idle. My Jeep now sounds more like a muscley SUV and less like a screaming loud 68 Camaro. If you're looking for a deep sounding muffler that's not too loud, this is a great option. I could tolerate it being a little louder but once I upgrade my intake and put on headers it'll be perfect.
I got this muffler with Kolak's kit but 130 seems to be a good price for it by itself.