You're still a fool for thinking this. Please stop being ignorant. Just because the header has two outlets doesnt mean that it goes to two different cats, mufflers, tailpipes, etc. I guarantee I know much more about jeeps than you. I've picked up a lot of things since Ive been on here. I've got a 98, but does anyone on here have an 00-01? Can anyone post some pics? You just have a problem with assuming. You know what they say about people that ASSume right?PurpleCherokee said:
How free flowing should the XJ exhaust be?
- Thread starter Quills
- Start date
But answer this purplecherokee, have you ever noticed the stock replacements get sold in front and back (3 cylinders each), that obviously means they aren't one part and they eventually Y down into a single entry into the cat. I know its not hard to understand and I wish someone on here with an 00-01 would chime in to give me some more validity.
Here's another link. Dont bother with the pics because they are obviously for a 4 cylinder, but please give reading a shot kid.
http://parts.jpartsonline.com/buy.php?make_text=jeep&model_text=cherokee&ml=cher-sport_4wd-002&year=2001&part_name=exhaust_manifold&brand_name=crown&make_code=JP
Here's another link. Dont bother with the pics because they are obviously for a 4 cylinder, but please give reading a shot kid.
http://parts.jpartsonline.com/buy.php?make_text=jeep&model_text=cherokee&ml=cher-sport_4wd-002&year=2001&part_name=exhaust_manifold&brand_name=crown&make_code=JP
alex22
NAXJA Forum User
- Location
- CT: waterbury area
Do you have two mufflers or one with two inlets and two outlets? This is a long thread and i have forgotten if you are running cats or not, if so, do you have two of those? Do you have any better pictures of your system?
~Alex
~Alex
Forget all this dual exhaust and hiflow cat nonesnse.
Try my new "turbotips" exhaust technology guaranteed to give +20hp and +20tq !
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Then with my "hypercharger" intake system, get an easy 150hp and 150tq for thousands less than products that actually work !
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.
Try my new "turbotips" exhaust technology guaranteed to give +20hp and +20tq !
http://images.channeladvisor.com/Sell/SSProfiles/43000222/Images/3/62-1625e.jpg
Then with my "hypercharger" intake system, get an easy 150hp and 150tq for thousands less than products that actually work !
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hurry order now, supplies are limited !
.
wolfpackjeeper
NAXJA Forum User
- Location
- 500' and 500KCAS, RAF lakenheath
I love it.
I tell you that I think dual on a cherokee are pointless and give you a mechanical reason why, and instead you call me an idiot and tell me I know nothing, good credibility there. I think you have fallen into the category of people who see performance gains because they paid for them and want to see them.
I know exactly what manifold you are talking about, pacesetter makes one like it, most of the kits I have seen like that come with a nice ypipe to connect the two as part of the kit. the reasoning for it being more or less what I said. the performance gains to be had on a single bank of cylinders is lost after the collector. It is more efficient from a flow velocity standpoint to merge the banks in order to maintain the flow velocity.
I tell you that I think dual on a cherokee are pointless and give you a mechanical reason why, and instead you call me an idiot and tell me I know nothing, good credibility there. I think you have fallen into the category of people who see performance gains because they paid for them and want to see them.
I know exactly what manifold you are talking about, pacesetter makes one like it, most of the kits I have seen like that come with a nice ypipe to connect the two as part of the kit. the reasoning for it being more or less what I said. the performance gains to be had on a single bank of cylinders is lost after the collector. It is more efficient from a flow velocity standpoint to merge the banks in order to maintain the flow velocity.
Hey Purple, I know clifford has been in the jeep aftermarket business for years and is a reputable co. like hesco. I am curious as to what their header looks like and if you could get pics of yours posted, it might(might) reduce the tension around here a bit(or at least back your words up a bit).
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alex22
NAXJA Forum User
- Location
- CT: waterbury area
seanyb505
NAXJA Forum User
- Location
- Simpsonville, SC
PurpleCherokee said:
Well lets look at this. Six cylinders. 6. Two collectors. 2. Downpipe brings it all together to how many? 1. 6-2-1. How do you think that is isnt 6-2-1? How many mufflers do you have?
wolfpackjeeper
NAXJA Forum User
- Location
- 500' and 500KCAS, RAF lakenheath
I got 30 total when I did lt's and a lid on my camaro, after a tune. The 4.0 header is not bad, it is already a tube design, lt's are good but most have a primary diameter that is based on V8 flow not L6 flow
PurpleCherokee
NAXJA Forum User
- Location
- MO
BBeach said:
BBeach said:
I'm a fool for thinking that dual exhaust out performs single exhaust??? Wow... do I really need "mechanical proof" that dual exhaust performs better than single exhaust??? And that's funny, because my exhaust system (and any true dual exhaust system) DOES have dual mufflers and pipes all the way back. Sounds like you "just have a problem with assuming". "You know what they say about people who ASSume right"? And btw, my Jeep IS a 2000 and trust me, it didn't (nor will any other) come stock with dual exhaust. What part of STOCK do you not understand? Crown, is NOT STOCK. It's called AFTERMARKET.
alex22 said:
2 1/8" pipes, dual resonators, no cats, and a dual in/out X-pipe muffler. The "resonators" are just glasspacks, and here's the muffler: http://www.dynomax.com/products/ultraflox.html
wolfpackjeeper said:
Sorry, but you're just plain wrong. Let me educate you on a little something I picked up in some mechanical and aerospace engineering classes. Air flows better (more effeciently) not through a single larger diameter tube, but through many tubes of a smaller diameter. In other words, a bigger scale example would be that an 8" tube has an area of about 50.25 square inches. An array of 16 tubes 2" in diameter also has an area of right at 50.25 square inches. But the 2" tubes will outflow the 8" tube even though they have the same area. Hmmmm... what's that remind you of? Maybe a single 2.5" exhaust pipe vs. dual 2.125" exhaust pipe? Simply put, it flows much better. Why do you think a 24 valve six cylinder or a 32 valve eight cylinder head will outflow a 2 valve per cylinder head even though the 24 or 32 valve head has smaller valves? It's the same principle. Smaller pipes and more of them. And if that's enough, just look at ANY high performance car and notice what kind of exhaust they have.
I guess you didnt realize I'm saying you're a fool for thinking that I think jeeps come with stock dual exhaust when the entire time im saying dual outlet headers. I guess with tards like you I must be very very specific or else you start assuming im crapping on your super duper exhaust. Do you honestly think I've spent the last 4 years of my life in a bubble, not understanding anything about jeeps and just posting for the hell of it? Like I said, I've picked up a few things and obviously dont think that jeeps had a true dual setup, but rather the dual outlet exhaust manifold. Crown is an OEM replacement. OEM style, oem everything. I dont even think mopar sells exhaust manifolds anymore, and if they do...they usually have to go through a company like crown or the like.
And as far as what you said to wolfpackjeeper....You have 2.125 pipes huh....You remember a post a little while back about lingenfelter having a 600hp vette and using pipes close to that size. Your jeep is making a third of that power....Plus dont forget the whole diameter vs velocity debate. Especially with the less restriction you have now (read: a good thing, although not environmentally/legally), you have an even lesser need for larger pipes. You just doubled the area of a 100% stock setup while also decreasing the restrictions considerably.
And as far as what you said to wolfpackjeeper....You have 2.125 pipes huh....You remember a post a little while back about lingenfelter having a 600hp vette and using pipes close to that size. Your jeep is making a third of that power....Plus dont forget the whole diameter vs velocity debate. Especially with the less restriction you have now (read: a good thing, although not environmentally/legally), you have an even lesser need for larger pipes. You just doubled the area of a 100% stock setup while also decreasing the restrictions considerably.
wolfpackjeeper
NAXJA Forum User
- Location
- 500' and 500KCAS, RAF lakenheath
you keep mentioning high performance cars that have dual exhaust, I never disagreed with that, It is better to have them on a High performance......V8. How about we look at some inline six cylinder cars that are high performance. Two buddies both have turbo supras, both make well over 400hp, neither one has a dual exhaust.
Seriously, they have 2 exhaust manifolds, thus the 2 outlets. You have one. And I never said anything about having a huge pipe diameter. I would love to see a flow meter of some sort put to your exhaust showing that it flows anything other than marginally better than a single outlet design. My single outlet exhaust has a higher flow out the back just by feel than my friends cammed v8 mustang. His is strait through, you could drop ping pong balls in his headers and have them come out the tailpipe.
Seriously, I know we are all enthusiasts on here, but who really considers a cherokee a High Performance vehicle. My posts have been about whether it is worth it to dual out a cherokee, money/gain wise, but since you cant seem to counter that argument you just argue that high performance cars all have that type of exhaust so obviously it is worth whatever it cost on my cherokee.
F-Body V-8s, most would argue are a performance vehicle. NONE have a dual exhaust setup, I guess if it was that important maybe the manufacturer would have found a way to do it
Seriously, they have 2 exhaust manifolds, thus the 2 outlets. You have one. And I never said anything about having a huge pipe diameter. I would love to see a flow meter of some sort put to your exhaust showing that it flows anything other than marginally better than a single outlet design. My single outlet exhaust has a higher flow out the back just by feel than my friends cammed v8 mustang. His is strait through, you could drop ping pong balls in his headers and have them come out the tailpipe.
Seriously, I know we are all enthusiasts on here, but who really considers a cherokee a High Performance vehicle. My posts have been about whether it is worth it to dual out a cherokee, money/gain wise, but since you cant seem to counter that argument you just argue that high performance cars all have that type of exhaust so obviously it is worth whatever it cost on my cherokee.
F-Body V-8s, most would argue are a performance vehicle. NONE have a dual exhaust setup, I guess if it was that important maybe the manufacturer would have found a way to do it
Speaking of Supras, last year at the Pittsburgh Vintage Grand Prix(I highly recommend going if you live w/in 6hrs of Pitt or take a mini weekend vacation--thousands of awesome automobiles), there was one Supra on the golf course with a big turbo and a 6" exhaust all the way to rear--was kinda ridiculous, but the whole car was professionally done(probably 500+hp). Speaking of HP, weren't the cheap dyno pulls you were considering this past weekend(I still want to get a baseline on the 96 engine before the stroker)?
PurpleCherokee
NAXJA Forum User
- Location
- MO
BBeach said:
Ok, fine "tard", show me a stock jeep with dual outlet headers. Please.
And as far as a Lingenfelter Vette having 2.125" exhaust, you're again, just plain wrong. A 600 horsepower Lingenfelter Vetter has 3" exhaust and it's for a REASON.
Ok, for one thing, horsepower is a RATE, not a VOLUME. But what IS a volume is engine size. Which is why engine size matters when it comes to pipe size, but not horsepower. Ideal individual pipe diameter difference between a 4 liter engine and a 7 liter engine is actually minimal. Especially when being split across two pipes since you've then halved the difference in pipe diameter per pipe.Do the math buddy. 2.125" pipes flow almost exactly half the volume of 3" pipes. WOW, that's weird! Because a Vette motor has almost exactly DOUBLE the volume of an XJ!!! It's almost like they engineered it to be that way!!! Isn't that weird???
Another thing you've failed to wrap your brain around is the fact that your engine is essentially a pump. Compare it to an electric pump, it doesn't matter how powerful the motor is, the pump is only gunna flow how much the intake and "exhaust" allow it to flow. Therefore, your intake and exhaust mods are VERY important especially if you do plan on doing more than just intake and exhaust. Having an efficient intake and exhaust system will make every other mod you do more effective.
wolfpackjeeper said:
Ok, lets talk high performance straight six's. How bout the highest performing straight six, the BMW M3. Wait what kind of exhaust does it have? Oh, DUAL 2.25" exhaust. Wow... that's weird. Cause ya know, I'm sure BMW knows nothing about performance just like I do. I mean, they only get a measly 300+ horsepower out of that motor. But yea, you're prolly right, dual exhaust only does any good on V8's. And the reason your buddies' supras don't have dual exhaust is because they're SINGLE turbo Supras :dunce:. If they wanted to double their horsepower numbers, they could run a twin turbo set up with DUAL EXHAUST.
wolfpackjeeper said:
The number of exhaust manifolds you have has NOTHING to do with anything. Only how many outlets the manifold has matters. I could take a two piece exhaust manifold and weld the two pieces together with a piece of steel stock and whoopdy freakin doo I've now got a one piece dual outlet manifold. And mine has TWO outlets, hence the DUAL exhaust.
So if your single outlet exhaust flows better than your friends cammed Mustang "just by feel", then why don't you bring your "feel-o-meter" over here and see how much better my dual exhaust flows than single exhaust?
gradon said:
Yes they were. And they freakin got rain/sleeted out :flamemad:. So I guess I'm just gunna have to wait. But wait, why do you wanna know about the dyno pulls if they're not gunna mean anything anyways?
:wave: Just messin w/ya buddy :cheers:I think knowing your vehicle's specs is very informative--I just didn't think you could say this is what this exhaust setup added when you didn't get the baseline and were gonna use what Jeep says the stock specs were(many of us know the torque spec was low-balled). I'm totally about modding my Jeep, so Kudos(and I hope my #'s are better than yours, lol).
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PurpleCherokee
NAXJA Forum User
- Location
- MO
Haha I do too man. Hey if you can pull it off better than I can, then tell me how and I'll be happy 
Here is a previous post by Ehall....I'll respond to the rest later...
What does Borla say -- http://www.borla.com/faqs/#7
Quote:
Q. Is a bigger pipe and muffler system better?
No, there has to be a balanced design to enhance the maximum engine output, exhaust gas velocity, and sound. If the diameter of the tubing is too large, the exhaust gas velocity will be reduced and rob the exhaust of thermal efficiency. Unfortunately we often disprove accepted racer mentalities like bigger is better. We must spend a great deal of energy explaining to someone how a 4" exhaust pipe will not work as efficiently as a 3" pipe. That is hard sometimes, but it is why we have magazine editors. Even with our excellent "track record" winning more professional car races than all the other muffler makers combined, we still often have to prove our theories to very well know top racers. One of these issues is volume versus velocity. The late John Lingenfelter helped us prove this over and over with his legendary Corvette exploits. People were often amazed how he would run 600 plus horsepower Vettes with 2 1/2" exhaust. If 4" would have made John go faster, he would have run it. We need to have a pipe large enough to overcome the boundary layer restriction in a dynamic flow situation while maintaining exhaust speed and evacuation. This isn't a simple axiom to understand, but the second best explanation is to say in race classes where let us say the budgets are seldom limited and the rules are not restrictive regarding exhaust, you will observe much smaller exhaust header tubing and exhaust pipes than some kids run on their 190-horsepower hand-me-down Honda sports compacts on the street.
I wonder if they know anything about exhaust systems
What does Borla say -- http://www.borla.com/faqs/#7
Quote:
Q. Is a bigger pipe and muffler system better?
No, there has to be a balanced design to enhance the maximum engine output, exhaust gas velocity, and sound. If the diameter of the tubing is too large, the exhaust gas velocity will be reduced and rob the exhaust of thermal efficiency. Unfortunately we often disprove accepted racer mentalities like bigger is better. We must spend a great deal of energy explaining to someone how a 4" exhaust pipe will not work as efficiently as a 3" pipe. That is hard sometimes, but it is why we have magazine editors. Even with our excellent "track record" winning more professional car races than all the other muffler makers combined, we still often have to prove our theories to very well know top racers. One of these issues is volume versus velocity. The late John Lingenfelter helped us prove this over and over with his legendary Corvette exploits. People were often amazed how he would run 600 plus horsepower Vettes with 2 1/2" exhaust. If 4" would have made John go faster, he would have run it. We need to have a pipe large enough to overcome the boundary layer restriction in a dynamic flow situation while maintaining exhaust speed and evacuation. This isn't a simple axiom to understand, but the second best explanation is to say in race classes where let us say the budgets are seldom limited and the rules are not restrictive regarding exhaust, you will observe much smaller exhaust header tubing and exhaust pipes than some kids run on their 190-horsepower hand-me-down Honda sports compacts on the street.
I wonder if they know anything about exhaust systems
Something else for you to look at when you're talking about our head flow from Dino's 4.0 page. HP is a good way to look at torque produced (which is related to the gas in the cylinder as well as engine rpm (more rpm's means more cfms). CFMs is a big part. Think of volumetric efficiency too, im sure the vette has much better flowing heads and such as well.
HO head #7120 & #0630
Valve lift (in)... 0.1 ... 0.2 ... 0.3 ... 0.4 ... 0.5 ... 0.6
Intake flow.... 66.0 128.0 179.0 206.0 209.0 209.0
Exhaust flow. 55.0 100.0 120.0 136.0 141.0 141.2
HO head #0331
Valve lift (in)..... 0.2 ... 0.3 ... 0.4 ... 0.5 ... 0.6
Intake flow.... 114.0 165.0 194.0 199.0 205.0
Exhaust flow....94.0 117.0 126.0 130.0 133.0
HO head #7120 & #0630
Valve lift (in)... 0.1 ... 0.2 ... 0.3 ... 0.4 ... 0.5 ... 0.6
Intake flow.... 66.0 128.0 179.0 206.0 209.0 209.0
Exhaust flow. 55.0 100.0 120.0 136.0 141.0 141.2
HO head #0331
Valve lift (in)..... 0.2 ... 0.3 ... 0.4 ... 0.5 ... 0.6
Intake flow.... 114.0 165.0 194.0 199.0 205.0
Exhaust flow....94.0 117.0 126.0 130.0 133.0
