hey guys i have a 305 in my 84 Z28 it has the usual holley carb, performer intake, bigger cam (not sure of specs, but 15-16" vacuum at 900 rpms) 700r4 w/shift kit 3.73 and will soon have a new limited slip. right now i have a 3inch i-pipe back into a flowmaster 80 series with dual 2.5 inch tips, but im wonder if maybe i would be better of with a single 3" tailpipe system ie: 3inch i-pipe to mac 3" offset/offset to single 3" tip. the reason i' m considering this is that it is quite loud but also i feel it has to much resonance and is just a little louder than i would like. so what do you think of the single 3" tip idea? would this increase my perofrmance or decrease or remain the same

 

Do you have a cat? I'll assume you do not.

The resonance is probably coming from the lack of a cat. For a 305, the performance difference between what you have and what a single outlet muffler would offer would be next to nil. I chose that muffler because I liked the balanced look of dual opposite outlets better than a single or same-side duals, and figured the 305 wouldn't overwhelm the muffler.

To cure the resonance, put a 3" Bullet muffler where the cat is supposed to be.

 

Keep the setup you have...Just add a second muffler like Five7 said. It doesn't have to be some awesome muffler...Just a straight-through style that won't fall apart after a few months.

 

sorry i have a catco 3in high flow cat, basicly i just want a muffler slightlt quieter than the 80 series i have now and while im at it figured i would get one that would flow better than the flowmaster cause from what i have read on here they are less than ideal what do you think?

 

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the flow 80 aint that loud. LOL

try edelbrock muffler

its quiet and flows a ton

 

If you still wanted the flowmaster sound, but quieter and don't mind the single outlet, you could get a 50 series. It's only 1 or 2" longer.

 

I have a Single In / Out Flowmaster 40 DeltaFlow (supposed to lower interior resonance) Its as load if not maybe a little louder than my old Flowmaster 80. The 40s does have some interior resonance but at cruise with the radio on you can’t hear it at all, with the radio off it’s hardly noticeable.

Here is a small video of it the day it was installed its oggten a little louder with age as do all flowmasters.

http://members.***.net/-nuclear-/going.mpg

PS I bumped the Shifter into nuteral on accedent and i also know now my tail light is out.