<VV> Non-turbo mufflers restrictive?

[Bill Elliott]

In terms of backpressure, baffled mufflers are the worst. The "turbo" muffler was the first design of its type. Still significant backpressure, but much better 
than the baffled mufflers.

Modern turbo mufflers are a quantum leap above the original. Some (like the Walker Dynomax series or Flomaster) have nearly the same flow as a stright 
pipe. Very low backpressure numbers.

Surprisingly, some of the loudest mufflers (Cherry bombs, glasspacks, etc) generate high levels of backpressure. The better designed ones (Walker 
TurboTube, Smithy's, the old "straight Thrush" are better, but still only about equal to the better turbos (and with the side effect of a lot more noise).

I run 2" diameters Walker Superturbos on stock 140 U-pipes. Almost the same power as straight pipes.

For a 140 with a manual trans, the top end power difference is noticable. For a PG, you'll get better overall performance with the stock mufflers due to 
better low end torque.

Bill Elliott

On Sun, 21 Nov 2004 22:05:06 -0500, RKAT wrote:

>I have been reading about the turbo mufflers being restrictive. How
>bad/good are the non-turbo mufflers? I purchased a set of mufflers from
>one of the vendors, and have not installed them yet on my 140. Would I
>be gaining much by going with a more free flowing muffler on the 140?