Another exhaust question.

[jmpSHO]

If the SHO motor needs a certain amount of back pressure to gain or keep its low-end torque then what is the benefit of an after market y-pipe? Why not just keep the stock y-pipe and all it's restrictions. Just in case anyone is wondering I am mostly referring to an ATX since that's all I own except a non-running MTX.

 

[FastAndFurious]

People get aftermarket y-pipes to get better top end.

 

[zblackbeast]

Theres a difference between restriction and over ****....

 

[LOUDSHO92]

The stock MTX y-pipe has too much resriction.

 

[shobote]

The stock ATX y-pipe does not have the restrictive 90 degree bend that the MTX y-pipe has. The bigger gains with the equal length ypipe upgrade are for the MTX.

 

[frosho]

If the SHO motor needs a certain amount of back pressure to gain or keep its low-end torque... [snip]

That's a myth. It takes velocity, not pressure, to optimize the scavenging effects of the exhaust gas.

The stock ATX y-pipe does not have the restrictive 90 degree bend that the MTX y-pipe has. The bigger gains with the equal length ypipe upgrade are for the MTX.

I'll vouch for this, the SHO Source equal length pipe rocks.

 

[K-Dawg]

What he said.

 

[PJV9126]

Alright I have a question then related to this. (don't mean to hijack but its easier than making a new thread). I have a 95 MTX. If I wanted a new Y Pipe would it be best to go with cats or without. I am a fan of the low end torque. Without cats does it lose a ton of torque? If it has them is there still gonna be an addition in the power?

Thanks

 

[SHOtime2511]

Alright I have a question then related to this. (don't mean to hijack but its easier than making a new thread). I have a 95 MTX. If I wanted a new Y Pipe would it be best to go with cats or without. I am a fan of the low end torque. Without cats does it lose a ton of torque? If it has them is there still gonna be an addition in the power?

Thanks

no,if you use the proper size piping you will not loose but gain torque.
as someone has stated exhaust requires speed or velocity and good flow.
a balance between the two is the goal of a good exhaust system.

in an optimal system the balance between the two is achieved with pipe size and proper bends as opposed to obstructions to flow,I.E. converters.

 

[PJV9126]

So then an equal length pipe like the one from sho source without cats would give me torque because it is bent better and flows better than stock? I guess what effect (if any?) do the cats have on the power? Why would someone get them versus not get them?

 

[jedhead]

I got cats with my y-pipe because I need to pass smog and why pollute when its not necessary. Cat-less pipe also causes more rasp in the exhaust sound.

Bob

 

[jmpSHO]

The stock MTX y-pipe has too much resriction.

If you read my post I was referring to an ATX.

 

[K-Dawg]

I use cats because they seem to sound better and I don't like my car to stink.

 

[SHOtime2511]

So then an equal length pipe like the one from sho source without cats would give me torque because it is bent better and flows better than stock? I guess what effect (if any?) do the cats have on the power? Why would someone get them versus not get them?

depends on your plans with your car,how much you drive it ext.
cats won't have enough effect on power really one way or the other,at least not enough for you to notice.

 

[illSHOyou]

Back pressure has nothing to do with making power. Velocity is everything. More importantly, the events that are happening and there timing when that exhaust valve opens. Every change made to a exhaust system alters the events and timing of pulses around the exhaust valve. Those changes can be merge points, muffler choice, system length, pipe diameter, collector length, collector diameter, primary diameter, primary length, etc...

Building a good exhaust on a car is more like trial and error. There isn't no exact science on it. There are some good guidelines, but in the end slap parts on and dyno test...