High clearance exhaust?

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Whaler27

Whaler27

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That's beautiful.

I wasn't aware there were parts of the country with no hot-rod industry (other than extremely rural areas where there are no services of any kind, of course.) That's hard for us to imagine out here. On the west coast you can't swing a dead cat without hitting an automotive shop of some kind, so even folks who live in the middle of nowhere are within driving distance of a custom exhaust solution. The shop I went to is in an unincorporated area near Eugene, Oregon, but it's not the only one nearby. A quick Google search suggests there are at least a dozen such shops within a 90 minute drive, and that's just exhaust places. We also have lots of fab shops with mandrel bending.

I was looking at the slip on solutions because I was thinking in terms of a tuned solution I knew I could do easily in my shop, and I wouldn't have to use a rare day off to get the work done -- but I was fortunate the shop was able to work me and get the job done quickly in on a Saturday off.





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mgroeger

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I have the Hooker Blackheart hi tuck axle back on the Mrs. Jeep and it is barely louder than stock at idle and normal acceleration and has a nice little growl when you jump on it. She's had her Jeep on some pretty gnarly trails at gnarly angles and practically vertical and the only damage was the tip of the tailpipe got a little banged. Muffler itself is perfect still. To my knowledge she has yet to bang up the resonator so it's staying put for now.
 

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thestein13

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I have the Corsa Sport 21013 axle back installed. There is a quieter Touring version.
It's smaller than the stock muffler so it'll definitely give more ground clearance.

So far, no drone that i've noticed...but it is quite a bit louder when i'm on the gas.
I am looking at getting the same exhaust. Will you post a picture? If you were to buy again, would you stick with the sport or go with the touring?
 

FrostQ

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The Sport is definitely louder. I’m still undecided on whether or not I would prefer it over the quieter Touring version. I love driving this solo, but I’d like a quieter one to chauffeur the family around.
One thing for sure is that it sounds awesome. Nice and deep with a nice tone. The vids on YouTube doesn’t do it any justice.
inside the cabin you can definitely hear it. Acceleration over 3k rpm and you can’t really carry on a normal conversation. Cruising is nice without drone. But you still notice the sound back there.
Bottom line is...if you want it louder than stock. Get the Sport. But if you just want to change the tone then get the Touring.
It feels much more like a toy with the Sport. No more minivan exhaust.
 

thestein13

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The Sport is definitely louder. I’m still undecided on whether or not I would prefer it over the quieter Touring version. I love driving this solo, but I’d like a quieter one to chauffeur the family around.
One thing for sure is that it sounds awesome. Nice and deep with a nice tone. The vids on YouTube doesn’t do it any justice.
inside the cabin you can definitely hear it. Acceleration over 3k rpm and you can’t really carry on a normal conversation. Cruising is nice without drone. But you still notice the sound back there.
Bottom line is...if you want it louder than stock. Get the Sport. But if you just want to change the tone then get the Touring.
It feels much more like a toy with the Sport. No more minivan exhaust.
Awesome, I'm going to get the sport. Thanks for the info and the pics!
 

AnnDee4444

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Nobody around here has a mandrel bender, so if you want a constant cross sectional area you've got to order a pre-made system or piece it together yourself. I've done that before and was hoping to avoid the hassle. Here is the system I build for my CJ-7.

Pic262.JPG


Pic264.JPG



Pic265.JPG
It almost looks like you built a set of 180° headers... had to do a double take. Nice work!
 

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It almost looks like you built a set of 180° headers... had to do a double take. Nice work!
Thanks!
Actually, they are 180° Tri-Y headers. My own invention. Overlapping exhaust pulses from each bank are kept in separate tubes until they join in the single 4-1 collector. The primaries are 1.75", secondaries are 2" and the collector is 3.5" which splits to dual 2.5" mufflers. Trusty old AMC V-8 dyno'd at 480 ft-lb and 437 HP.
 

Kreepin1

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For those not familiar with 180° headers, almost all V-8 engines utilize a cross-plane crankshaft which is an inherently balanced design (like straight six engines). The tradeoff is that the firing order can't alternate between banks creating a situation where one exhaust valve opens while another is not done with it's cycle, creating a bit of a traffic jam in the exhaust manifold. While this is happening, there is no exhaust being dumped into the other manifold, creating a bit of a vacuum due to momentum of the exhaust stream. This is what gives V-8's with a dual exhaust that classic burble and why X or H-pipes make power, they help even out the flow through the mufflers. It also is impossible to get the same consistent cylinder to cylinder scavenging you get in a 4 cylinder engine.

There are two typical solutions. You can utilize a flat-plane crankshaft as Ferrari and Ford's latest GT350 do (which required dealing with the unbalanced crank somehow) or build a 180° header which routes the offending cylinders to the opposite bank.

On my CJ-7 I didn't have room to run an exhaust down the passenger side as the transfer case has been clocked flat. But I needed more flow so I came up with this contraption. It keeps exhaust pulses separate until they reach the collector and is almost equal length (#6 and #8 are off).

Funny story: While on the dyno the guy's nephew ran in to see what was going on. The exhaust exits from the roof with no muffler and he said it sounded like we had a superbike on the dyno. Why? Because with the evenly spaced exhaust pulses my V-8 at 5,500 rpm sounds like a superbike at 11,000 rpm!
 

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Here is how this relates to our Jeeps. The engineers put that stupid exhaust loop in to equalize the length of the two banks to the muffler. If you take it out you gain ground clearance but there will be a power drop unless you increase to a 3" exhaust system or run dual exhaust.
 

Chocolate Thunder

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Just picked up this one from northridge

https://www.northridge4x4.com/part/...-stainless-steel-cat-back-exhaust-system-3-6l

I mean for 273 shipped and it’s afe might as well give it a shot. Cheapest I saw it anywhere else was at least 100$ more, will report back.
I’ve seen that one for a while and it looks great except that I think it’ll increase sound levels more than I’d like. Would you post before/after sound clips when you install it? I know AFE has one but another can’t hurt. There looks like there’s room for a small muffler to be installed immediately after the resonator if it’s too loud so I may end up doing that if it’s too loud as is.
 

Adventure.AS

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I’ve seen that one for a while and it looks great except that I think it’ll increase sound levels more than I’d like. Would you post before/after sound clips when you install it? I know AFE has one but another can’t hurt. There looks like there’s room for a small muffler to be installed immediately after the resonator if it’s too loud so I may end up doing that if it’s too loud as is.
I deleted the factory muffler and installed the Flowmaster American Thunder Axle back exhaust (817837). I found it a bit too loud so I had a shop weld in the Flowmaster Series 40 Muffler (952549) just aft of the factory resonator. To me (and my wife) it sounds find, with just a hint of rumble. No drone.

Flowmaster American Thunder Axle back exhaust 817837.jpg


Flowmaster Series 40 Muffler 952549.jpg
 

Chocolate Thunder

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I deleted the factory muffler and installed the Flowmaster American Thunder Axle back exhaust (817837). I found it a bit too loud so I had a shop weld in the Flowmaster Series 40 Muffler (952549) just aft of the factory resonator. To me (and my wife) it sounds find, with just a hint of rumble. No drone.

Flowmaster American Thunder Axle back exhaust 817837.jpg


Flowmaster Series 40 Muffler 952549.jpg
The “axle back exhaust” looks like just the end section of the exhaust with no muffler. A muffler delete. You removed the OEM muffler and replaced it with the delete pipe pictured above, and also welded in the 40 series in-line. Got any sound clips or photos of what it looks like?
 

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