Thinking of going to a dual system with two mufflers and an x pipe on my silverado 5.3. The truck is basically a stock LM7 with 243s milled to 61cc, stock cam, Volant CAI and stock manifolds and cats. It's a DD type truck so I don't want to loose low end.

I'm leaning towards dual 2.25" pipes for this setup but not sure if 2.5" would be better? What are you guys running is stock-ish trucks?

I'll be using 5x8x14 or 5x8x18 Magnaflow mufflers and a Magnaflow x pipe.

Anyone have sound clips of a dual with 14" vs 18" length mufflers?

 

On a stockish 5.3 I'd run 2 1/4 if going true duals as I feel that dual 2.5 would be overkill and may slow down the exhaust velocity, affecting low end performance. You may find some vids on Youtube btw...

 

2 1/4 is the way I'm leaning. It flows slightly better than single 3". Now the question is do I want to run 5x8x14" mufflers or 5x8x18" mufflers. I don't want it too loud but not too quiet either. I currently have a single 3" 5x8x14 Magnaflow on it and like the volume level but want the tone of true duals with an x pipe.

 

what year is this truck?


personally i would go 2.5s.. 18" mufflers

 

It's an 06' with an LM7 and 243 heads milled down to keep compression at 9.5:1. Stock manifolds and Y pipe with cats. I would just cut the Y off and run duals down the passenger side after the cats.

It has stock cam, intake manifold, TB. It has a Volant intake and exhaust will be pretty much the only performance mod. It has been tuned for 89 octane by myself.

 

i still say 2.5

 

2.5" with 18" case mufflers is sounding good. I think that it won't really loose any low end with pipes run all the way to back bumper.

I remember when I did duals on my old 98' 5.7L I ran dual 2.5" x pipe into dual 2.5" pipes into Flowmaster 40s and then 2.25" pipes out of the mufflers to the back. It ran well and makes less power than this truck.

 

Just think about any mods U may do later when will want 2.5 just a thought

 

That is true, but this is nothing but a DD. I have a ton of parts and time wrapped up in my TBSS and Camaro. I just want a good sounding exhaust without loosing low end performance for this truck. This truck will not be seeing any more mods other than CAI and Exhaust and Tune.

I think I will split the difference and go 2.5" from the x into the mufflers and 2.25" out for the tailpipes