need some advice

[19Walt93]

I have 2 1/2" single exhaust with cast iron manifolds on both my 351 Ranger and 13 second 302 Mustang. The engine doesn't care how many exhaust pipes you have as long as the flow isn't restricted. A single 2" system should be plenty for a 2.9 unless the goal is to make more noise.

 

[jerkyboyxiii]

I have a flowmaster super 44 on my 01 ranger, and it sounds really nice. My wife's Colorado has the same muffler. Her inline 5 banger sounds better than my 4'oh sohc, IMHO. I had dual super 44s on my 08 5.4 f150. They sounded nice too. Im a big fan of super 44s.
To add: all of my exhausts get dumped before the rear axle.

 

[19Walt93]

I have a flowmaster super 44 on my 01 ranger, and it sounds really nice. My wife's Colorado has the same muffler. Her inline 5 banger sounds better than my 4'oh sohc, IMHO. I had dual super 44s on my 08 5.4 f150. They sounded nice too. Im a big fan of super 44s.
To add: all of my exhausts get dumped before the rear axle.

Flowmasters sound good if they have a little help to get rid of the hollow tin can sound. If you used them behind cats that would do it. I put the engine out of my Mustang into an 81 Cougar sedan in 2009 with a 2 1/2" single system, a 50 series Flowmaster and an 18" glass pack behind it. It had a nice deep sound and wasn't too loud.

 

[lil_Blue_Ford]

A single 2.5” will flow enough for a modded 4.0 OHV, that’s what’s on my Choptop with a 4.0, I did headers, high flow aftermarket cat, and it currently has a Flowmaster 10 series (I told the shop I wanted a 40 or 44, but they did what they wanted). It’s alright, surprisingly somewhat quiet at idle but gets loud at higher RPMs. Before the 4.0, it had a 2.9 with no headers, high flow cat, and Flowmaster 40. I want to say it might have been 2.25” pipe back then. I was pretty happy with it.

For true duals on a 2.9, you would need 2” pipe if not smaller. There’s a good argument for smaller unless it’s a heavily modded engine and if you’re gonna go that far, you might as well go to a 4.0, which is basically a bored and stroked 2.9 for the OHV. My green 2000 Ranger with a 5.0 got headers and dual 2.5” exhaust which is more than adequate, it should be plenty for handling the engine mods I have planned. I did dual high flow cats and a Magnaflow crossover muffler to save space and eliminate the need for an X or H pipe for exhaust scavenging.