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Resonator Delete, X/H Pipe Question

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539
687
Exp. Type
Time Attack
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3-5 Years
SoCal
Looking for cheap weight reduction and I think an X/H pipe is next on my list but I have a couple questions.

1. I see some for $100 and others for nearly $300. For such a simple part, does the quality vary that much? Is a $300 pipe really worth while over a $100 version?
2. X vs H? I know X generally gives power up top (per internet) and H gives power down low. Is one better for track driving? I suppose that would depend on the track though. Without a tune, would there be any power gain at all?

Thanks in advance!
 
price: difference is basically China vs US made. My noname ebay x pipe is doing just fine. For headers where there's a lot more thermal load you are taking more of a gamble, but for a resonator replacement its not as critical.

There may be a couple hp difference between an H and X, but mostly its the sound. H is older school american V8 sound and X produces a more european V8 sound.
 

Bill Pemberton

0ld Ford Automotive Racing Terror
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Blair, Nebraska
Also fit is usually better with the more expensive ( often American made ones ) and this may sound minor with an X/H pipe but you want things to line up as well as possible in my estimation.
 
303
371
CA
Depends on your muffler setup too. If you have a medium-loud set of mufflers on the car right now, and then go to an offroad x, the sound may be too loud for your liking.

Offroad H-pipe adds some rasp, a lot of volume. But overall quite nice.
Offroad x pipe added insufferable amounts of rasp, crazy amounts of volume. I don't understand how people drive their car on the street like that.

However I will say, x-pipe "smoothes out" the sound in the upper RPM range, say 5-7K rpm, whereas the H pipe does the opposite, the sound gets strained and unrefined at high RPM from my experience.

I don't have dyno sheets to back it up or anything, but it seems common for OR/X pipes to gain more HP than OR/H pipes.

In regards to tunes:
I can't speak to coyote, but for me a tune was necessary for two reasons: 1.) You get a CEL if you go catless (CEL is usually catalyst inefficiency) 2.) For my car, it ran about 3% lean after a midpipe swap. My tuner said I wouldn't need to re-tune, but after putting my car on a dyno, it was running about 4% lean, which is too lean for a track car. So 3% fuel was added with my handheld.

Good luck
 
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Bill Pemberton

0ld Ford Automotive Racing Terror
8,422
8,346
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
I have a LTH x-pipe and it sounds great on the street and track, and I am not sure it is the cause , but there is a lovely cackle on track under downshift/braking .
 
539
687
Exp. Type
Time Attack
Exp. Level
3-5 Years
SoCal
Depends on your muffler setup too. If you have a medium-loud set of mufflers on the car right now, and then go to an offroad x, the sound may be too loud for your liking.

Offroad H-pipe adds some rasp, a lot of volume. But overall quite nice.
Offroad x pipe added insufferable amounts of rasp, crazy amounts of volume. I don't understand how people drive their car on the street like that.

However I will say, x-pipe "smoothes out" the sound in the upper RPM range, say 5-7K rpm, whereas the H pipe does the opposite, the sound gets strained and unrefined at high RPM from my experience.

I don't have dyno sheets to back it up or anything, but it seems common for OR/X pipes to gain more HP than OR/H pipes.

In regards to tunes:
I can't speak to coyote, but for me a tune was necessary for two reasons: 1.) You get a CEL if you go catless (CEL is usually catalyst inefficiency) 2.) For my car, it ran about 3% lean after a midpipe swap. My tuner said I wouldn't need to re-tune, but after putting my car on a dyno, it was running about 4% lean, which is too lean for a track car. So 3% fuel was added with my handheld.

Good luck
That's alarming...an x-pipe can cause it to run lean??
 
303
371
CA
That's alarming...an x-pipe can cause it to run lean??
Yeah, in theory it makes sense:

Exhaust is less restrictive, thereby allowing more air to enter into the engine (ie run lean if additional fuel isn't added to match the additional airflow). In a way it's sorta neat because it proves that the midpipe added power through increased total SYSTEM (ie intake, engine, exhaust) airflow.

The thing that is weird (and I imagine a coyote car won't have this issue) is the fact that my car didn't automatically add fuel on it's own. Stock tunes should be able to adjust for minor changes like that. So I think what I experienced is a bit of a fluke.
 
That's alarming...an x-pipe can cause it to run lean??

That would be very odd in normal circumstances with an Ecu and O2 sensors that are working properly. Short term fuel trim of 3-5% is well within normal bounds. Drive up to a track at 4k feet altitude and it will trim more than that out.
 
539
687
Exp. Type
Time Attack
Exp. Level
3-5 Years
SoCal
That's alarming...an x-pipe can cause it to run lean??

That would be very odd in normal circumstances with an Ecu and O2 sensors that are working properly. Short term fuel trim of 3-5% is well within normal bounds. Drive up to a track at 4k feet altitude and it will trim more than that out.
So resonator on stock tune should be fine?
I would also think the car should be able to measure the increased airflow and adjust fuel as needed.
I'd much rather weigh more than be lighter and potentially run lean.
 
539
687
Exp. Type
Time Attack
Exp. Level
3-5 Years
SoCal
Nah the Ecu is always monitoring air fuel ratio and adjusting. Of course for big changes a retune is needed but resonator delete is safe as the day is long. Same for axle back, nobody recommends returne for that, it’s within the ecu’s ability to adjust.
How about axle back AND resonator delete?
Sorry, just being careful
 

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