I'd install the H. The cost is nominal and it helps balance exhaust pressure and reduce drone. No material performance differential however.

 

Im getting my full Flowmaster exhaust "with H-pipe" hooked up Thurs. I ve never had an H pipe on it. so I am excited to see what happens. But I am jumping from 2 in to 2.5 so I wont know about difference the H pipe makes.

 

The H pipe does help a little and makes it sound better. I like the sound of the X pipe so that is what I am going to use.

 

I drove mine a few days without a H-pipe, then had one put in. In addition to mellowing the tone just a bit, there was a noticeable increase in torque.

 

A big Hot Rod dyno test about 25 years ago showed the crosstube was worth an additional 5-15 hp. Bottom line, Ford didn't invest 2¢ in any part in these cars unless it worked.

 

My problem with the X is similar. Basically, It converts the car to single exhaust with two mufflers. No matter how well it works, I just can't get past that.

 

So does an H. Any crossover whether H or X by design allows more ex system volume per cylinder. Basically if you have single ex from head pipe out back per side that flows 500 cfm, either crossover doubles that per cylinder....in theory. In reality there's still 8 cylinders filling the same 2 pipes. But, the effect of the cylinders from the opposite bank when connected by H or X tend to help scavenging as well as kill soundwaves. It's a proven fact the X makes more power than the H but the H maintains the true musclecar sound Ford and Mopar designed them for and still work as designed with a couple bonus hp. That said would I add either one on a daily driver? Nope. Not unless you're looking for that specific sound.

 

So does an H.

No, it does not. Connectivity is NOT the same as a single pipe.

If you saw through the middle of the X pipe, you get a single exhaust.

O

There is no point in the H pipe that you would not get two pipes.

O O

Even if you saw through the middle of the crosspipe, you still get two pipes.

O===O


So whether we're talking about this-

Or this-

You're really only arguing about the length of the single section.

It's a proven fact the X makes more power than the H

Not so fast. The specifics of any installation, and type of use can vary this a lot. Did you not read my66gt's post? Is he making it up?

I spoke to the guys at Pypes when the X-pipe first got popular. They found no real advantage to the X vs H in their testing, but demand due to the fad had them marketing the X in droves.

 

i've heard the x pipe is the way to go cause it works for every car. the H pipe is for sound and drone control. H pipes help performance wise if you are specially tuning and tweaking that motor in sync with the H pipe. so its mostly for a fine tuned racecar is what i got from all this. i'm doing an X. By the way, which trick flows do you have on your 302?

 

By the way, which trick flows do you have on your 302?

TFS 170's

 

I promise I'm not making it up. Granted these were full out race engines (Mopar in this case) but the X would give about 5-7 hp at the wheels in the 6500-6800 rpm range and were worse below 6500 and above 6800.

 

H sounds boring and cheap esp with boring old Flowmasters. I know I have them too.

X sounds more exotic even on Flowmasters.

I always thought X made more power becasuse the point was one side moving past or across the other was supposed to create a vaccum, and help pull exhaust out of the other side. I've had both on crazy high powered Mustangs and I say decide on the sound you prefer. I'm about to put an x pipe in with my flowmasters and if I still don't like it I'm getting some dynomax ultraflows to run with an x pipe.

 

We have an X-pipe on the race car and yes, it sounds cool coming out of the burn out box and at the top end at 7500 and 27 lb of boost but, on the Wife's car it will either be 2 straight pipes or an H. If the H will give a nice sound than that will be the choice--probably going that route, I figure that it can't hurt.

 

oh yeah well she may prefer the smoother sound of an H.

X pipes tend to sound meaner and nastier (to me more exotic and therefore more expensive sounding)

The general rule of thumb has been go with an H pipe with chambered mufflers, and an X pipe with straight though mufflers. Flowmasters and those similar hollow types of mufflers of being the exception in which case you can run either X or H pipes just choose the preferred sound.

 

Easier than explaining. Pay particular attention to the paragraph on page 2. This is real life hands on comparisons.


Exhaust

 

The miniscule performance difference in that test isn't enough to convince me. Too many variables are unaccounted for (at least in the writeup) that could skew the results. Add that to the fact that two of the companies listed there are pushing X type crossovers and I think it is more of a puff piece. I'd go with whatever sound you like to hear best. Personally I prefer the H and glasspacks. Based on the experience I've had in the past regarding performance I'd take the H in 90% of applications--even if it is contrary to popular opinion.

 

Like was already said there are many many variables when it comes to which system works best and how much power it makes....I think everyone can agree that either one will be of some benefit over straight duals....On a street car I would just go with which sound you like best..H pipe is a more of an old school muscle car sound and the X is a more raspy exotic type sound...I put an X pipe on my car at the recommendation of the muffler shop who bent up the system..I didn't really like it at first but it does sound good at higher rpms....I don't like the sound at idle as much as an H pipe..

 

lately I'm loving this exhaust set up below ...... see the videos

Motor: 302 block, 289 heads, mild cam, Edelbrock 1406 (600cmf) carburetor,

Edelbrock performer 289 intake manifold, Patriot mid-length headers, 2.5" X-pipe, dual Dynomax Ultra Flo Welded mufflers, pipe runs over the axles and turns down at the rear valance.

1966 Mustang Dynomax Ulta Flows 2.5" - YouTube

LELUS66 Mustang Driving 03-18-12 - YouTube

 

What mid length headers are you guys using with an. aod tranny? I'm assuming there is. It fitment issues with an aod trans and mid length headers like the patriot performance ones?