Muffler's effect on RPMs?

smalls · 08-18-2006, 05:49 AM

I added the flowmaster 40 series last week, and I will start off my saying that I love the sound. One thing I noticed on my way to work this morning is that I was was running close to 2000 RPM's at 60 where I used to only run 1800. Is this the effect of my dissapation of back pressure?

What can I expect from gas milage?

Any other effects I might notice?

haulin79 · 08-18-2006, 08:53 AM

The muffler has a large placebo effect.

Other than that, if the rpm change you noted is real, your transmission/clutch is or was slipping and is not related to your muffler in any way.

FJFlorida · 08-18-2006, 09:17 AM

I put a flowmaster 40 on my Defender and did not notice an RPM change, but it did help on gas mileage some. Now I get 4 MPG

smalls · 08-18-2006, 10:57 AM

maybe it runs higher RPM's first thing in the mornign when is isnt warmed up?

TBarnaby · 08-18-2006, 11:48 AM

Quote:

haulin79 previously said:

Other than that, if the rpm change you noted is real, your transmission/clutch is or was slipping and is not related to your muffler in any way.

+1...look to your clutch

cantdrive55 · 08-18-2006, 02:59 PM

It's impossible for a change in muffler to affect the RPMs of the car in gear.

A change in tire diameter or transmission will only effect the RPMs.