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Old 09-06-2012, 03:04 PM   #1 (permalink)
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Jeep Cherokee Chop Top: Opinions?

So I've been looking at "chop top" jeep xjs lately, like the one below. I like the look of them and the utility of the small pickup bed.

I know it's a major mod, but I was thinking that with a removable cover, like the on in the photo, except designed with an optimal curve and perhaps made from rigid materials, that you could see some serious drop in Cd.

In addition, you could create some nice mounts for a full boat tail & start your tail further up on the jeep, making the total length of the car w/ tail shorter than it could otherwise be. Not an improvement in Cd, but perhaps in handling and ability to park.

What's everyone's thoughts on this? are there significant gains to be made here compared to adding a full tail to a stock xj?

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Old 09-06-2012, 03:48 PM   #2 (permalink)
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Although the chopped XJs look amazing...note that they are unibody vehicles and cutting the rear will decrease the structural integrity of the Jeep. Not that big of a deal on the trail but if it's a highway car...you might want to reconsider.

Back to your question I would think that the chopped XJ with a full boat-tail would be more streamline than stock XJ with full boat-tail. i wouldn't chop it just for the mpgs though.
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Old 09-06-2012, 04:02 PM   #3 (permalink)
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That thing ain't gonna fall apart, especially with the added bars.
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Old 09-06-2012, 05:27 PM   #4 (permalink)
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Why not make a boat tail that attaches to the receiver?
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Old 09-06-2012, 05:40 PM   #5 (permalink)
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Yeah, you'll have a boat tail that's a couple feet shorter overall- if you can get the plan view taper in line with the profile. Plan on cutting the sides off too?

You'll surely get some nice percentage numbers from it- perhaps 15% FE improvement. But is it worth it to you for only 2-3mpg overall?
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Old 09-06-2012, 05:48 PM   #6 (permalink)
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Most of the boat tails don't even see 15%. You'd be lucky to see anywhere close to half of that.

My opinion is buy a car. Keep the Jeep for the weekends or whatever.
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Old 09-06-2012, 06:26 PM   #7 (permalink)
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Slant chop, from kach22i:
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Old 09-06-2012, 06:42 PM   #8 (permalink)
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thoughts

Quote:
Originally Posted by ac6404 View Post
So I've been looking at "chop top" jeep xjs lately, like the one below. I like the look of them and the utility of the small pickup bed.

I know it's a major mod, but I was thinking that with a removable cover, like the on in the photo, except designed with an optimal curve and perhaps made from rigid materials, that you could see some serious drop in Cd.

In addition, you could create some nice mounts for a full boat tail & start your tail further up on the jeep, making the total length of the car w/ tail shorter than it could otherwise be. Not an improvement in Cd, but perhaps in handling and ability to park.

What's everyone's thoughts on this? are there significant gains to be made here compared to adding a full tail to a stock xj?
You're whole thought process is perfectly linear to me.And I think you have a complete command of the logic surrounding boat-tailing.
If you are very attached to this kind of vehicle,and will be keeping it long enough to compensate for the time and material of the mods,then it looks like it's the best match for your project.
The roof profile will have a jump on the competition as far as pressure recovery goes,so length for length she'll have the advantage.
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Old 09-06-2012, 09:06 PM   #9 (permalink)
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I can see a few advantages to trying to eco mod a cherokee. First is, it would be pretty easy to hang chloroplast off of; there's "frame" rails and crossmembers and, because it is an offroad vehicle (sort of ..), none of that stuff hangs down

Second, you can find a bumper that is made for a winch. They stick out a bit and, by nature of their design, divert air around the front. If you cleeaned up the bottom, one of these bumpers would be perfect to "split" the air to the bottom.
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Old 09-07-2012, 11:55 AM   #10 (permalink)
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Over the years I've seen easily hundreds of this sort of chopped up "let's turn a SUV into a sorta sedan-truck thing!" idea. Most on 4x4 forums, a dozen or so in meatspace - I have yet to see one that wasn't terrible.

I think sometimes people just feel like they have to change something to change something, even if the end result is going to be worse than what they started with.

If you have it in your head that you've gotta do this, well then I guess get on it. Soon there will be yet another one of these on the road and after a few weeks of tolerating it you'll put it on craigslist because it was a terrible idea in the first place, and you'll never again hack up another car.. some lessons I guess you've gotta learn first hand. Enjoy!

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