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252,000+ Miles
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1,316 Posts
Discussion Starter #1 (Edited)
So, I have decided on a magnaflow 93422 cat and a magnaflow 15847 dual exhaust since I have my Tiregate to carry my spare, and I like the look/sound.

Since most of my engine to-do's are done, I need a new list...my manifold is cracked (but only leaks under a heavy dose of seafoam in the head) so it needs to go...the exhaust is 10 years old this July and still kicking, but I can convince the wife to let me upgrade if it's a budgeted replacement.

It also knocks one more thing off my list before getting a tune.

My question is on headers, specifically the JTR ceramic shorty vs the KPE shorty. I'm looking for bolt & go, but being in NYS I need to pass emissions tests both on the PCM and at the tip of the exhaust.

Anyone have any experience with either in NY?

And no, no interest in Al's headers or in the Magnaflow Manifold (since it's basically stock).

Advice/Opinions/Comments welcomed. (On any of the above)
 

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[MTS] Who is this guy?
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3,779 Posts
What year is your truck? Neither the JTR or the KPE will help you pass emissions any better than the other. The KPE is ready to go for 07+ trucks with 2 o2 bungs (plus has an o2 plug for 04-06), is stainless steel equal length, and requires no modification to anything whereas the JTR requires extended o2 wires, mild steel, but can be purchased ceramic coated. For performance the KPE is the way to go if not going long-tube.

Also, don't bother with the Magnaflow cat you won't see much in gains if any as our stock cats are already "high-flow."

As for the PCM on emissions testing: If you have an 04-06 you can get rid of the first cat and nothing will be triggered in the PCM. If you have 07+ I believe you will have to do the o2 non-fouler mod to not trigger an o2 code.

As for the sniffer, if the truck is warmed up it will pass emissions with only the second cat with no problem. The first cat is only there to aid in startup emissions.

As for visual inspection (if you have them) you will probably fail with a header either way but I really don't know. I'd imagine that would have more to do with the shop/person than your truck.
 

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252,000+ Miles
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1,316 Posts
Discussion Starter #3 (Edited)
No visual inspection that I know of. They need to pass the sniffer and the PCM.

I have an 05 (signature), so no worries on passing the emissions test is good to know.

Not really looking to go long tube, no worries there. Stainless or ceramic coated is fine by me.

What makes the KPE better than the JTR, other than the material? I thought someone said JTR's put about 10hp at the wheel. KPE's website is pretty crappy and vague with no actual mention of gains or engineering. Just "we sell it".
 

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[MTS] Who is this guy?
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3,779 Posts
No visual inspection that I know of. They need to pass the sniffer and the PCM.

I have an 05 (signature), so no worries on passing the emissions test is good to know.

Not really looking to go long tube, no worries there. Stainless or ceramic coated is fine by me.

What makes the KPE better than the JTR, other than the material? I thought someone said JTR's put about 10hp at the wheel. KPE's website is pretty crappy and vague with no actual mention of gains or engineering. Just "we sell it".
KPE is an equal length header which are generally* better than unequal length. Also, somewhere the KPE header was advertised as a gain of 27hp and 35tq on the 3.7 which we all agree is over-inflated...however the cat gut is dyno proven for 10 hp to the wheels and I noticed an improvement with the KPE header over my gutted manifold on my 3.5 so that should tell you something. Also, you can still ceramic coat the KPE as well but it really isn't necessary and the header looks better bare.

* rare cases when headers are specifically engineered to a single engine to match exhaust pulses with firing order, blah blah blah I don't know the individual specifics.
 

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[MTS] Who is this guy?
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I thought someone said the KPE was advertised as an equal length header but really wasn't when it arrived? I have to check the thread.
No the KPE is actually equal length...check out my thread in my signature. However, the Orion header is or was advertised as equal length but is not.
 
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