4/5" exhaust questions.

[brobeson]

It is my understanding that on our 24v trucks, most of the exhaust is 4".



Going down to 3" at the muffler.



If you remove the 3" and replace with a flow through type 4" muffler, wouldn't you have a 4" exhaust at a fraction of the cost of a complete system.



If so, what does a complete system offer that the stock system opened up to 4" does not?



TIA



Bob

 

[redneckdr]

exhaust

nope. the exhaust is mainly 3" expanding to 4" between the resonator and the inlet to the muffler. 3" out of the muffler to a 4" tip behind the wheel.

 

[fj40charles]

I think the exhaust bottleneck might be the factory downtube. This 3" downtube is press bent and it is not very smooth. Swapping out the factory muffler with a flow-through design would help.



Charles

 

[redneckdr]

exhaust

i know there are tdr members who believe that upgrading the exhaust doesn't help performance. i upgraded to a full 4" mandrel bent (vs the compression bent downpipe)system. if nothing else, it SOUNDS better, and looks better. i still can't believe the muffler isn't a sgnificant restriction, too. you can choose to leave the resonator in, use a 4"-3" adapter, then apiece of 3" pipe back to the current tailpipe relatively inexpensively. i tried it that way. TOO LOUD for my liking. i used a 4" straight thru truck muffler without a resonator. nice deep tone.

 

[fj40charles]

One thing I noticed after I put my 4" exhaust was faster turbo spool up and higher turbo boost. Before the exhaust, I was seeing max 28 lbs of boost. After the 4" exhaust, I can get to 30 lbs easily. Of course losing the factory muffler could have alot to do with this. Anyway, it was well worth the $425. 00 for my Jardine system.



Faster spool up, lower EGT, faster turbo cooldown, cool sound, and higher boost =



Another point. . I think having a different exhaust will make the duradud or powerjoke owner wonder about what you have under the hood and will usually leave you alone.



Charles