Exhaust help

I have a 302 2V 100% stock and will remain that way internally, and I want to free up the pressure in exhaust, but without permanently modifying the car, so drilling holes or wields are not eligible. I need to keep the cats and all other emission equipment. Plus I need to keep it as cheap as possible. Any suggestions….. Horse power is not the issue with a 2.47 rear end but sound and little mpg might be nice.


My thoughts……

Dual exhaust with stock manifold, cats, and small cherrys, out in front of the rear tire.

Or

Singe 3 inch a with stock manifold, performance cat, and small cherry out the back with twin tail.

Or

Leave it be…..

 

im not sure why you have to stay with a cat. if you are in California you can only have the same amount of cats that the car came with. so with that in mind i would replace the stock cat which origanly would have been a pellet type cat that is highly restrictive with a modern honeycomb style cat. then a 2.5" single exhaust following the factory routing out the rear of the car. a performance muffler of your choice for sound level will finish it off.
if your in a state the doesnt limit you to the factory cat location you can do a dual exhaust system. you can put exhaust hangers for the drives side system on the seat belt bolts that stick out. its hard to fit a tail pipe in on the drives side so its easiest to just have the exhaust dump before going over the back axle.

 

I vote leave it be.

 

Will this alone make a big difference? How much horse power and mileage can I expect with dual vs. single? In my state each pipe has to have a cat.

Why?

 

Run straight pipe without the muffler. The cats quieten it down more than the muffler does anyway.

 

Single pipe?

 

That's your call.

 

I was asking what you thought...


Does it need dual? Is it constricting?

 

The reason I ask is that 302 HO GT’s, 351 HO Trucks, and 351 HO Crown Vic all have single yet have at least 157 HP.

 

Run a dual 2.25 to 2.5 inch system or a single 3-3.5" pipe. I would try it without the muffler first, then if you don't like the sound, put a muffler on it.

 

Because you said you want to do it as cheap as possible. In that case...why do anything? With your motor described as: 302 2V 100% stock and will remain that way internally I don't see any advantages to be gained with any exhaust modification.

 

Ok, thanks.