X pipes???

[BTZ201]

Ok guys, I plan to fab a new 3" exhaust on my 75 gmc truck.
Motor for now is 350 with older nicely ported 034 bowtie heads, and a elgin 1090p elgin solid flat tappet cam. Just some old parts thrown together before the sbc 400 build.
This winter I plan to fab a new 3" exhaust with magnaflow type mufflers.
Planning to run an X pipe, are the stamped steel ebay type X pipes good or should I use another brand?
Or no X pipe?
Or should I run a H pipe?
Or none of these, just straight dual exhaust?
Sb 400 will be a little while from now, but thinking ahead...
I welcome any thoughts on this!!!
Thanks,
Brent

[mag2555]

A X pipe is the best and since your dealing with a truck you should have no issue getting one into the exh system unlike some cars where the sub performing H pipe is the only way to go!

[BTZ201]

Thanks Mag2555
Any thoughts on style of X pipe, have been looking at the stamped steel type?
Look like a little more volume then the other style?

[1980RS]

I have run the X pipe on my car with the 406 and have had great results using the 3" setup and 2 of the smaller case Flowmasters. Car has run low 10.90's@123.5 and with the other milder 406 ran 11.06@118mph.

[Moparboy440]

X-pipes does nothing to improve the flow of an exhaust. However they can reduce exhaust sound and drone.
https://www.dailymotion.com/video/x5s8nr8

[lefty o]

x or h, but buy a quality piece, not some ebay junk.

[GARY C]

I always use Jegs universal kit. https://www.jegs.com/p/JEGS/JEGS-Univer ... 2/10002/-1

[englertracing]

X-pipes does nothing to improve the flow of an exhaust. However they can reduce exhaust sound and drone.
https://www.dailymotion.com/video/x5s8nr8

Weird.
The video seems to show an h better than none. And an x slightly better

[dondon]

didn't big joe say that there were only helpful on grossly unpowered engines and he had 289 ford in parentheses.

[n2omike]

You can get HORRENDOUS results with a bad x-pipe. Some muffler shops (and individuals) will simply cut a hole in one pipe and run a second pipe through that hole. This cuts the area IN HALF in the best case scenario, killing power like adding a cork. In many scenarios, the hole is not cut well, and it ends up all boogered up with weld, absolutely killing flow. An X-pipe needs to be a merging of two mandrel bent pieces of pipe with the smallest area of the merge being LARGER than a single pipe. Welds also have to be CLEAN.

If an x-pipe is done 'right' it might be worth a little bit of midrange... similar to an H-Pipe... It will just sound a lot more shrill, like it is turning an extra 3k rpm. lol.. which is what a lot of people are after when installing one.

[Moparboy440]

X-pipes does nothing to improve the flow of an exhaust. However they can reduce exhaust sound and drone.
https://www.dailymotion.com/video/x5s8nr8

Weird.
The video seems to show an h better than none. And an x slightly better

Average power was basically the same for all three and within dyno variance for a Carbureted engine.

[eric8]

You can get HORRENDOUS results with a bad x-pipe. Some muffler shops (and individuals) will simply cut a hole in one pipe and run a second pipe through that hole. This cuts the area IN HALF in the best case scenario, killing power like adding a cork. In many scenarios, the hole is not cut well, and it ends up all boogered up with weld, absolutely killing flow. An X-pipe needs to be a merging of two mandrel bent pieces of pipe with the smallest area of the merge being LARGER than a single pipe. Welds also have to be CLEAN.

If an x-pipe is done 'right' it might be worth a little bit of midrange... similar to an H-Pipe... It will just sound a lot more shrill, like it is turning an extra 3k rpm. lol.. which is what a lot of people are after when installing one.

Oh I know from experience!

883B6422-B436-427D-8654-2AA86AE6E65B.jpeg

0F07BA8D-2A6F-4D54-B84F-30A237022785.jpeg

[eric8]

Just FYI if you want a little sound attenuation you can go this route. This is what I used to replace the soup sandwich of an X pipe shown above. Magnaflow part number 11385 for the 2 1/4” version, and 11386 for 2.5”

AB7D874C-26D2-451B-8363-65D261A9BDEA.jpeg

5CB5AE3D-5BFD-4FFD-A00D-3C05517C885E.jpeg

[BradH]

I like an x-pipe better than an h-pipe because it helped reduce some mid-range drone in the car, plus it's slightly more "mellow" at lower RPMs. I'd have to search to see if any of the old tests comparing x vs h are still around online, but *usually* an x-pipe was worth "something" in terms of ET & MPH, all else being the same.

I've run x-pipes in two different configurations:
- Dr. Gas 3.0 x 3.0 into 3" mufflers w/ 2.5" tailpipes; car ran as quick at 10.9s, typically low 11s, and was surprising quiet
- TTI 3.0 x 3.0 setup shown in attachment w/ 3" mufflers and 3" tailpipes; car ran mid-to-high 10s and was "not as" quiet w/ the larger tailpipes

FWIW, the red rectangles on the image are where I'm considering adding AR chambers after the x...

[Bill Chase]

Optimal placement from the primary pipes end seems to be key, trouble is most chassis rarely allow 100% optimal placement. Strongly suggest having someone run the numbers through pipemaxx. Safe to say they do more than cut noise, if that's all they did I doubt you would see them on newer model performance vehicles from the factory.

Khaos motorsports makes a nice 3" x, superb design, excellent welds, and priced good.