Dynomax Ultraflo Catback For 8.1l

Hulk1999 · June 6, 2009

Just wanted to tell everyone that I installed a dynomax ultraflo catback on the big block yesterday evening. It was easy as hell, the hardest part was getting the old one off (stock 3 inch with a magnaflow muffler). It's got a deep thoarty sound too it but it isn't annoying at highway speed. I have to say that i'm really happy with it. Feels like when i get on it, throttle response is better. It was also cheap, i spent $332 total (including tax and shipping). Better yet dynomax has a $75 rebate. It takes the stock 3 inch pipe and turns it into a 4 inch pipe from the cats back and a muffler that looks like a huge cherrybomb and finishes up with a 5 inch stainless steel tip. Something else i found is I can take the muffler and tailpipe off leaving the 4 inch Y-pipe and clamp the stainless steel tip on it. Talk about rumble.

Hulk

dewfpo · June 6, 2009

You have to posts pics and sound clip now.

DEWFPO

Matt427 · June 6, 2009

...i spent $332 total (including tax and shipping). Better yet dynomax has a $75 rebate...

Where did you buy it from?

Hulk1999 · June 7, 2009

...i spent $332 total (including tax and shipping). Better yet dynomax has a $75 rebate...

Where did you buy it from?

Summit Racing

Kodiak450 · June 11, 2009

Was the catback exhaust a T304 stainless steal exhaust?

Hulk1999 · June 11, 2009

Aluminized Steel

rick graffrath · June 18, 2009

is that the same kit for the 6.0 motor too? if it is,dynomax(walker) should keep that for just the 8.1 engine. the engineer i talked too about the noise and resonance problems said if my truck was a 8.1 eng, i wouldn't beleve the difference in sound from 6.0 to 8.1. he said it was actually quieter with no interioir sound issues.

L29er · June 19, 2009

good choice on the exhaust! I have the same on my BB, fricken love it! If you have headers it sounds even better!!!!

Hulk1999 · June 19, 2009

is that the same kit for the 6.0 motor too? if it is,dynomax(walker) should keep that for just the 8.1 engine. the engineer i talked too about the noise and resonance problems said if my truck was a 8.1 eng, i wouldn't beleve the difference in sound from 6.0 to 8.1. he said it was actually quieter with no interioir sound issues.

Just looked on the Dynomax website. Says it's the same for the 6.0. Compared to the Magnaflow i had on there, it's way better. Took a 300 mile trip last weekend and it was quiet in the cab at 65-70mph. I like it a bunch

Hulk1999 · June 19, 2009

good choice on the exhaust! I have the same on my BB, fricken love it! If you have headers it sounds even better!!!!

Thanks!, the only reason i got it was ease of installation and 4 inch pipe size (factory is already 3inches). Sound and performance were an added bonus. I wish someone made some longtube headers for my truck. The only ones i saw were the shorty style. Not worth the money according to most people.

Hulk

ss502gmc · June 19, 2009

Does this exhaust seem to give you any more power or just sound? Im asking because my stock muffler has a hole in it on the top somewhere and i wanted to get a nice custom exhaust but money is tight now and i saw you said it was only like $300 so i am considering this now. also do you know how it compares to a 50series flowmaster?

Hulk1999 · June 19, 2009

Does this exhaust seem to give you any more power or just sound? Im asking because my stock muffler has a hole in it on the top somewhere and i wanted to get a nice custom exhaust but money is tight now and i saw you said it was only like $300 so i am considering this now. also do you know how it compares to a 50series flowmaster?

the seat dyno says more power. But that's only percieved. it does flow better too. But if i were u i would get a aftermarket muffler or fix the other (if you can). From what i heard, the stock exhaust flow good already but mine had a magnaflow muffler on it and the previous owner did a bad job putting it on. it was queit and rusted. I think what people are doing is cutting the pipes behind the cats and putting two 44series flowmasters mufflers with tips. I might do that a year or two down the road. Look on youtube for it. It's sounds pretty good. Also i've heard good things about Flow Pro mufflers. Then again there's always no mufflers. I don't have any expiernces with flowmasters other then youtube. If money's tight, get creative. I got a money from going TDY.