scottgjerdingen

I'm doing the 496 mec exhaust on a 454 upgrade and I currently have a back end on the exhaust that is reduced to 3" all the way out the back.

SO, the 3" components are on their way out and my immediate thought was to start looking for 4" components. But then I started to wonder why limit it at 4" and would larger be more free flowing?

My tips sit just a couple inches above the water line at idle so I am going to want some good external flappers.

Would it make any sense at all to go larger that 4"?

Thanks!

- scott -

thirdchildhood

iTrader: (6)

4" is plenty for a 496. It is what my 525 has.

pqjack

+ 1

scottgjerdingen

Interesting, let me direct the question in an opposite direction.

Am I possibly over estimating the need to replace the 3" exhaust with a 4"? What would I be leaving on the table in terms of HP if I leveraged the existing 3"?

Unlimited jd

iTrader: (5)

Back pressure will help scavenging and increase torque to an extent. Under 550hp I would say 3" is fine under 650 4"

scottgjerdingen

Based on thread feedback I went and measured the inner diameter of my current exhaust tips. They appear to be a bit oblong with a hight of 2.5" and a width of 2.25", is this reasonable for a 3" exhaust?, is there value in getting tips that have a larger inner diameter? then back to the original question, if I am going to replace stuff anyways, is there value in going larger?

Thanks!

- scott

Griff

Use 4" exhaust tips. 4" is pretty much standard

scottgjerdingen

LOL I love the affirmation of coming full circle :-)

Thanks guys!