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Jeep Wrangler TJ Coil-Over Conversion - Coil Correction

Part II: TJ Coilovers For The Rear
By Christian Hazel
Wrangler Coil Over Conversion Front
Wrangler Coil Over Conversion Setup
Here's Miller's pre-conversion... 
   
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Wrangler Coil Over Conversion Setup
Here's Miller's pre-conversion setup. With 3-inch Teraflex coils, 8-inch Walker Evans shocks, and a Currie AntiRock it's actually a great suspension. Although the rear hit the bumpstops on compression now and again, the 9 inches of travel wasn't too shabby. However, in the interests of more potential suspension travel, a cleaner design, and our nagging, Miller removed, cut, and ground the factory spring and shock mounts off the frame and axle tubes for our cameras.
Wrangler Coil Over Conversion Cutoff
Step one is to get happy with... 
   
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Wrangler Coil Over Conversion Cutoff
Step one is to get happy with the cutoff wheel and grinding discs, eliminating the factory coil and shock mounts from the frame and axle tubes. Miller also relocated his Currie AntiRock from its rear-mounted position to in front of the axle centerline just under the tub.
Wrangler Coil Over Conversion Tacking
It's not a Ted Nugent zebra... 
   
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Wrangler Coil Over Conversion Tacking
It's not a Ted Nugent zebra thing, but rather measurement markings off a known location on the frame rails for the swaybar links. Miller test-fit a couple locations for the swaybar end link mounts on the axle and the swaybar mount on the frame before finalizing this arrangement. Miller built some mounts with some 3/16-inch steel plate, a band saw, and a hole saw before tack-welding them into place.
Wrangler Coil Over Conversion Mounting Kit
We ordered a rear coilover... 
   
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Wrangler Coil Over Conversion Mounting Kit
We ordered a rear coilover conversion mounting kit from Gen-Right Off Road (PN RSM 1001), as well as some limiting straps and pirated the 10-inch Walker Evans shocks (PN 700-16-010) that the Jeep was running up front. We put these 12-inch units (PN 700-16-012) in their place. As usual, Eibach had the right combination of coils to hold up the 4,500-lb Jeep.
Wrangler Coil Over Conversion Custom Application
Gen-Right designed its kit... 
   
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Wrangler Coil Over Conversion Custom Application
Gen-Right designed its kit to run 14-inch coilovers with the coil buckets mounted at a 10-degree angle, but Miller went custom on his application. That's the nice thing about Gen-Right coil buckets; you can easily make them work for your application based on your needs and wants. After determining his ideal location with tire clearance, shock movement, and shock mounting height taken into consideration, Miller used the buckets to trace where the cutout needed to be made. Note the extra material on the mount below the framerail allows the buckets to be mounted taller for longer-travel shocks.
Wrangler Coil Over Conversion Cut
You can use a plasma cutter,... 
   
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Wrangler Coil Over Conversion Cut
You can use a plasma cutter, but you'll have better results using a thin abrasive cutoff wheel on an angle grinder or pneumatic cutoff tool. The notch is pretty substantial, but so is the construction of the Gen-Right buckets. Be sure to thoroughly clean any rust, paint, or undercoating from inside and outside the frame rails in preparation for welding.
Wrangler Coil Over Conversion Test Fit
With the shock buckets tacked... 
   
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Wrangler Coil Over Conversion Test Fit
With the shock buckets tacked in place, Miller test-fit the shocks with no springs so the position of the Gen-Right shock mounts could be determined on the axle. As it turns out, we were a bit hasty in our positioning of the lower mounts, welding them on before fully-cycling the suspension with the coils in place. Doh!
Wrangler Coil Over Conversion Travel
Once we installed the coils... 
   
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Wrangler Coil Over Conversion Travel
Once we installed the coils and cycled the suspension to full droop we discovered that increased travel and position of the axle shock mounts allowed some contact with the side of the bucket. Our fix was to raise the shock mounts closer to the top of the axle tube. This not only pulled the coils away from the side of the shock buckets at full droop, but allowed the axle to drop out a bit further.
Wrangler Coil Over Conversion Lift
Up front we wanted to keep... 
   
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Wrangler Coil Over Conversion Lift
Up front we wanted to keep the Jeep's 3.5-inch lift height while curing the front shocks' tendency to top out. The 12-inch stroke coils shod with 150lb over 400lb Eibach springs did the trick. Miller set up the front with five inches of uptravel and seven inches of droop, which he finds perfect for his wheeling.
Wrangler Coil Over Conversion Arms
The finished installation... 
   
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Wrangler Coil Over Conversion Arms
The finished installation out back shows the modified Currie AntiRock swaybar arms that were shortened for clearance. Although shortening the arms stiffens the swaybar's spring rate, Miller reports the Jeep is much more stable on the road now, but off-road flex isn't affected. In reality, the old swaybar was probably too soft with the longer arms needed to reach the axle tubes from the swaybar's old mounting position above the rear bumper.
Wrangler Coil Over Conversion Position
If you undertake a conversion... 
   
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Wrangler Coil Over Conversion Position
If you undertake a conversion like this yourself, don't forget to think in three-dimensions when cycling your suspension and checking your coil bucket mounting position. Notice the clearance between the bottom of the bucket and coils. There's plenty of clearance when the suspension is at rest or dropped out equally on both sides, but when the axle articulates side-to-side, the spring comes pretty close to the bucket.
Wrangler Coil Over Conversion Angle
With a 61-inch WMS-WMS measurement... 
   
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Wrangler Coil Over Conversion Angle
With a 61-inch WMS-WMS measurement on the rear axle and 3.5-inch backspacing on the wheels, Miller reports no tire interference on the coilovers. With the relatively steep 34-degree mounting angle, Miller upped the spring rate and added a couple clicks on the rear shocks' compression adjustment knob and went a bit heavier on the coil rate, at 225lb over 400lb springs. Remember, you'll need to weigh your Jeep and take your shock angle into consideration when choosing your spring rates for optimal performance.
Walker Evans Racing
2304 Fleetwood Dr.
Riverside
CA  92516
Gen-Right Off Road
805/584-8635

genright.com
TAG Motorsports
800/928-1766

tagmotorsports.com
Eibach Spring
800/507-2338

eibach.com

Jeep Patriot Research
Jeep Patriot Our comprehensive information will allow you to compare the new Jeep Patriot and review specs, photos and more. The 2010 Patriot comes with a L4 standard engine and has a manufacturer suggested retail price of $22,740.00. It has drivers side crash test ratings of 4 stars and passengers side crash test ratings of 5 stars. Other similar vehicles are the Jeep Wrangler and the Jeep Liberty.

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