Hello

Has anyone have experience determining the difference between the two exhaust systems (x-pipe & h-pipe) on the FE 360 or 390?

I am planning to put long headers on my 360 (along with 390 manifold or Edler pro and longer rods later on). With this in mind - how should I go about determining the right pipes?

I was thinking of just running straight pipes out of long headers - would it be an overkill considering the amount of noise it will create.

Any info is valuable and appreciated.

Thanks,
Nick

 

If fabbing yourself, the H is easier to fab than an X.

Performance-wise, toss up! But I would go with an H given the RPM range of FEs in a truck.

Tubing... 2.5-inch tubing maximum. Again, based on RPM and typical HP numbers. And the cost difference between 2.5- and 3-inch tubing is significant. Your call but technically 2.5-inch duals are appropriate.

Obnoxious and loud trucks are for kids... be an adult about it. Headers and straight pipes might result in finding a brick on your bench seat.... and a side or rear window shattered.

.

 

Most of my vehicles are y pipe but if given the choice I'd run neither unless someone has a good reason to put them in

 

X-pipe: Mid-pipes built with a crossover, or "X" shaped design, purposely cross exhaust streams to even out flow and streamline exhaust gasses through the rest of the system. X-pipes are generally raspier and louder than H or Y-pipes and have been shown to provide slightly more power than their counterparts. You are likely to see most of the power gains higher in the rpm band with an X-pipe.

H-Pipe: An H-pipe is better at balancing sound and produces a more consistent, classic muscle car growl. It does less than an X-pipe in the way of balancing exhaust gasses but still flows quite well. H-pipes maintain the back-pressure necessary for torque gains earlier in the rpm band, as opposed to the top-end power seen from an X-pipe.

 

Dose it matter on the location of the h pipe was thinking making it bolt in and close to the drive shaft input to the c6 on mine or skipping it all together using long headers and thrush turbo mufflers
Just a daily driver with a holly and alumin intake

 

Your decision to leave hp and tq unrealized is OK by us.

 

Do you need to connect the two sides, would dual exhaust not work better and easier?

 

It is a dual exhaust system we are discussing... and whether configuring the dual exhaust as an X or connecting each side with an H pipe (tube) is better.

"Need"? No. But there are marginal benefits by doing so.

.

 

Are you making a tractor pull truck? Losing torque down low is, like beauty, in the eye of the beer holder.
I have dual 3 inch pipes with an X-pipe on a little old 347 and I have no issues with bottom end torque.
What it boils down to is what do you want? An fe has more bottom end then my motor. There are a few articles and info on proper placement of a X-pipe, with enough digging can be found. It involves a crayon and trial and error to see where the crayon melts on the exhaust pipes.

 

I was going to stay out of this but ya know. I personally prefer the burble you get with dual exhaust and no crossover at all, added benefit easier to install/ fabricate.

 

Sounds good to me. Thus trying to balance it out with the proper hardware. If I were to install straight 2.5 piping what mufflers would be sufficient to provide reasonable sound without an overkill on loudness.

Also, I saw few trucks having double exhaust with mufflers run to the mid section of the truck and end it there with tips pointing downward. Is that enough piping to have the exhaust muffled down to create a good balanced burble.

Thank you

 

I run ultra flo mufflers they are really only loud when you get on it, with a nice sound at idle and my exhaust ends with turn downs before the rear axle under the bed.

 

So HIO you would recommend a 2.5" vs a 3" exhaust? How so? I was going to run a 3 in all the way back on my 347.

 

I have done a lot of experimenting with exhaust over the years. If you are towing and need the low end torque the H-Pipe is ideal. I run a modified 460 with 2 ½’s and the H-Pipe into Wicked Flow straight thru mufflers. They are loud but since I am a 78-year-old kid I love them. It pulls my 7.5K 5th wheel like a beast.

 

Yes..2.5-inch duals for typical rigs.

If going merged, 2.5-inch tubes into a dual inlet muffler and a single 3-inch outlets OK too.

In my book, 3-inch duals is for 450hp or more and at sustained RPMs.