Mufflers ?

I wasn't sure where to put this question as it applies to both of my vehicles with big block and small block .
So I drive both of these on the street and I also race with them mostly 1/8 mile.

My question is what are your thoughts about mufflers and power loss ? I would like personal experience accounts and not internet copy and paste.
I just installed a pair of spin tech mufflers on the small block car and future plans are to install them on the big block car.
Thanks Whitefield

whitefield wrote:I wasn't sure where to put this question  as it applies to both of my vehicles with big block and small block .
So I drive  both of these on the street and I also race with them mostly 1/8 mile.

My question is what are your thoughts about  mufflers and power loss ? I would like personal experience accounts and not internet copy and paste.
I just installed a pair of spin tech mufflers on the small block car and future plans are to install them on the big block car.
                                   Thanks Whitefield

I tested a bunch of 3" mufflers a few years ago for my Engine Masters Contest entry and I can tell you for sure that although doing a decent job of quieting, the Spin-Tech's were the absolute worst for power.
Use the muffler you can actually see through with the largest volume body which you can fit under the vehicle, for noise and resonance reduction.
The long, square oval ones from "Extreme Technologies" were all around the best:  www.extrememufflers.com

EDIT: I looked-up that actual number ... 1018-3030

From my EMC testing MagnaFlows did very well.