California TJs: muffler, cats, and emissions

wmblore

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What are our choices for the 3 cats, muffler and piping if you live in California in regards to power, performance or sound. I am not interested in swapping stuff out every two years.

What are you CA. people doing for full exhaust packages? Mine is all stock now and ready for upgrade.
 
You're not going to gain much power from anything that you're talking about, honestly. The only way you'll gain some real power is with something like this (and a good tune):

https://americanracingheaders.com/collections/jeep/products/jeep-1998-2006-tj-4-0l-long-system
You can tinker with it all you want, but none of those bolt-on cats you'll find are going to do anything for you beyond negligible and immeasurable gains IMHO.

The real restrictive point on the 4.0 (and I've learned this from talking to Golen and Charles from Magnum Power) is the exhaust manifold and cylinder head. If you open up that exhaust manifold with a set of full headers like I linked to above (NOT any of the other b.s. half headers such as Banks and the likes) and pair it with a good tune (i.e. HPTuners software), you'll pick up sometimes as much as 30 extra horsepower.

But with any of those bolt-on Magnaflow, Borla, or other systems, you may as well just burn your money, as you'll be pissing it away.

Keep in mind (and I always say this), the 4.0 has more in common with a tractor than it does a Ferrari.
 
You're not going to gain much power from anything that you're talking about, honestly. The only way you'll gain some real power is with something like this (and a good tune):

https://americanracingheaders.com/collections/jeep/products/jeep-1998-2006-tj-4-0l-long-system
You can tinker with it all you want, but none of those bolt-on cats you'll find are going to do anything for you beyond negligible and immeasurable gains IMHO.

The real restrictive point on the 4.0 (and I've learned this from talking to Golen and Charles from Magnum Power) is the exhaust manifold and cylinder head. If you open up that exhaust manifold with a set of full headers like I linked to above (NOT any of the other b.s. half headers such as Banks and the likes) and pair it with a good tune (i.e. HPTuners software), you'll pick up sometimes as much as 30 extra horsepower.

But with any of those bolt-on Magnaflow, Borla, or other systems, you may as well just burn your money, as you'll be pissing it away.

Keep in mind (and I always say this), the 4.0 has more in common with a tractor than it does a Ferrari.

And a TJ is about as aerodynamic and a tractor also
 
You're not going to gain much power from anything that you're talking about, honestly. The only way you'll gain some real power is with something like this (and a good tune):

https://americanracingheaders.com/collections/jeep/products/jeep-1998-2006-tj-4-0l-long-system
You can tinker with it all you want, but none of those bolt-on cats you'll find are going to do anything for you beyond negligible and immeasurable gains IMHO.

The real restrictive point on the 4.0 (and I've learned this from talking to Golen and Charles from Magnum Power) is the exhaust manifold and cylinder head. If you open up that exhaust manifold with a set of full headers like I linked to above (NOT any of the other b.s. half headers such as Banks and the likes) and pair it with a good tune (i.e. HPTuners software), you'll pick up sometimes as much as 30 extra horsepower.

But with any of those bolt-on Magnaflow, Borla, or other systems, you may as well just burn your money, as you'll be pissing it away.

Keep in mind (and I always say this), the 4.0 has more in common with a tractor than it does a Ferrari.

I do agree with Chris that if you want performance gains you must go all-in with headers back and a tune. Those headers that lead to one car, I don't think, are street legal, so you may need to think of that if you have emissions testing in your area.

I recently went through buying a muffler and determined that Borla makes a higher quality muffler than most, but it's loud. So if you are looking for quality and loud I would grab that one.

I went with the Banks which is half the price of Borla, not as loud but made out of stainless steel 409 instead of SS304 like the Borla.

Quadratec sells a SS304 Mopar

https://www.quadratec.com/products/17603_7100.htm
 
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Thanks guys. I wasn't really looking for power as much as my old exhaust is in need of updating and I live in California so emissions test is every two years. I do not mind loud and Stainless is preferred.
 
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I do agree with Chris that if you want performance gains you must go all-in with headers back and a tune. Those headers that lead to one car, I don't think, are street legal, so you may need to think of that if you have emissions testing in your area.

I recently went through buying a muffler and determined that Borla makes a higher quality muffler than most, but it's loud. So if you are looking for quality and loud I would grab that one.

I went with the Banks which is half the price of Borla, not as loud but made out of stainless steel 409 instead of SS304 like the Borla.

Quadratec sells a SS304 Mopar

https://www.quadratec.com/products/17603_7100.htm
Do you have a link to the banks one you went with?
 
I do agree with Chris that if you want performance gains you must go all-in with headers back and a tune. Those headers that lead to one car, I don't think, are street legal, so you may need to think of that if you have emissions testing in your area.

I recently went through buying a muffler and determined that Borla makes a higher quality muffler than most, but it's loud. So if you are looking for quality and loud I would grab that one.

I went with the Banks which is half the price of Borla, not as loud but made out of stainless steel 409 instead of SS304 like the Borla.

Quadratec sells a SS304 Mopar

https://www.quadratec.com/products/17603_7100.htm
You are correct the one Chris linked was "off road use only."
 
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Thanks guys. I wasn't really looking for power as much as my old exhaust is in need of updating and I live in California so emissions test is every two years. I do not mind loud and Stainless is preferred.

I am lucky enough to have a home in Calaveras County and they do not require smog testing in that county so all of my cars are registered there and not in Contra Costa County :cool: where I actually live
 
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I do agree with Chris that if you want performance gains you must go all-in with headers back and a tune. Those headers that lead to one car, I don't think, are street legal, so you may need to think of that if you have emissions testing in your area.

I recently went through buying a muffler and determined that Borla makes a higher quality muffler than most, but it's loud. So if you are looking for quality and loud I would grab that one.

I went with the Banks which is half the price of Borla, not as loud but made out of stainless steel 409 instead of SS304 like the Borla.

Quadratec sells a SS304 Mopar

https://www.quadratec.com/products/17603_7100.htm
X2 with the Banks, better sound note than stock but not an obnoxious drone like some others. Stainless steel great fit and CARB legal
 
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