I have a 85 TPI 305, with usual low-buck mods ( Ported Plenum, airfoil, no screens, gutted air box, K&N's, no cat, Corvette Servo, etc)! It is low miles, still has stock G.M. crossflow muffler, and stock exhaust manifolds. With no cat, it sounds pretty strong this way. Has anyone out there tried the Dynomax Welded Ultraflow #17227 on a 3rd, or 4th Gen, 305 or 350, with or without cats? This muffler flows something like 940 C.F.M, by far the best flowing crossflow around. If so, how do you like both the sound AND performance gain? I'd be changing it mostly for performance, but am wondering about sound level of these also. Also, I've been told that due to the straight through design of these, and the fact that it's a crossflow style, that most of the exhaust goes through one of the tailpipes more than the other(?!?!?). Has anyone else found this to be true? Thanks in advance!

 

Alright, has anyone tried ANY Dynomax Ultraflow crossflow, or even their Super Turbo crossflow, and what did you think. I know everybody digs Flowmasters, but that might be a little loud for what I'm looking for. Opinions?

 

I actually have a dynomax super turbo on mine. The previous owner put it on the car. I like just fine. It is, however, only slightly louder than stock. As far as perfornance goes I couldn't tell ya, I haven't really pushed my car to find out.

 

I have their Magnaflow brand muffler. Looks like a glasspack but is pretty mellow at cruise and loud enough at WOT.

 

Nice photo, James_85Z28! That puppy looks like it would flow great, and roar at WOT! What kind of muffler did you have prior to that one and did you notice any performance difference with this one? Thanks, man!

 

I have an Ultra-Flow.....the SS polished one....i love it....it is pretty loud and i like the sound and it does not rust.... It came with the car as part of a cat-back. I also had the Super Turbo...it was alot quiter.

 

I had the Flowmaster 3" single in/out muffler that came with the american thunder system. It sounded cool but my car became louder and louder and then sounded crappy and was unbearable at even part theottle. So I wanted something that walked a little softly but still let me carry a big stick so I got the magnaflow, which has to flow better than the flowmaster, but is still quiet at cruise and idle, and sounds cool idling when stopped. My flowmaster sounded nasty and too loud because my cat hit too many speed bumps and blew out the exhaust. I found that out when I didn't pass smog a few weeks ago.