New Ford Racing Products SOHC kit...

[Afboy143]

...their new exhaust kit utilized dual 2.5" mufflers, and an X pipe, full 2.5" piping....on an SOHC 4.0 motor (mustang 4.0 SOHC; however, we have the same motor)? I can personally attest that when I had dual 2.25" piping, I did lose low end....why would Ford Racing Products slap true dual 2.5" exhaust on a 4.0 mustang? Does the X pipe have something to do with making up for the lost back pressure? hmmm...those kits do sound amazing on the 4.0 mustangs tho...

 

[Rick]

My guess is they did it to meet the demand for a performance "sounding" exhaust. While it may lose low end torque, there will probably be an increase in peak HP. That way they can say it adds 10HP, or whatever. They just fail to mention that you won't be feeling that 10hp until you're up near redline.

You SOHC guys are lucky they put that motor in the Mustangs. The 4.0 OHV has been basically unsupported since it came out. Go figure... there are millions of them on the road yet barely any aftermarket support. When I bought my Explorer in '93 I fully expected that it would be supported by the aftermarket like every other Ford.

 

[Afboy143]

My guess is they did it to meet the demand for a performance "sounding" exhaust. While it may lose low end torque, there will probably be an increase in peak HP. That way they can say it adds 10HP, or whatever. They just fail to mention that you won't be feeling that 10hp until you're up near redline.

You SOHC guys are lucky they put that motor in the Mustangs. The 4.0 OHV has been basically unsupported since it came out. Go figure... there are millions of them on the road yet barely any aftermarket support. When I bought my Explorer in '93 I fully expected that it would be supported by the aftermarket like every other Ford.

Hmm.. I wonder exactly how much low end you lose. I know I lost a lot compared to a single pipe. They sound amazing though...very throaty.