I have been working on these for a while now and waited until I had a few sets made and my design worked out. These are to remove the torsion bar setup and install coilovers as the front suspension. My first thought was to use the LCA from a 2500hd, but it turns out the mounts for the arm are wider than the 1500s, and the steering knuckle is placed further out than the 1500s, so much for an easy swap using factory parts, so I made these brackets.
Why Coilovers?
There are several advantages to coil overs from torsion bars. The biggest one is they ride much, much better, and depending on what shocks and springs you use can have many different ride settings for many different conditions. Torsion bars, on the other hand, leave you pretty much stuck and only able to adjust shock dampening rates and not the spring rate itself. Many 4wd guys crank or decrank the bars to adjust ride height (yes this applies both to lifted and lowered guys), and this changes the ride drastically.
The torsion bar setups are basically meant to ride on the bump stops or slightly above them. On lifted setups when you crank the bars the ride is usually the biggest complaint since the bump stop is so far away its not used. On lowered setups its basically the same just the opposite direction and you are constantly riding on the bump stops even after trimming them.
Second advantage is going to be the huge selection of shocks and springs available in the aftermarket. I use QA1 shocks and hyperco springs, however king, fox, qa1, and whoever else make coilovers can be used. Spring wise, hyperco seems to offer the biggest range in lengths and spring rates that I could find, and they are well priced. I used 1000lb springs with qa1 ds301 shocks. The spring sounds stiff but these shocks only have 2.5" of travel, and my truck weighs approximately 1250lb of sprung weight so in order to get in the middle of the shock travel 1250/1.25 = 1000lb. To calculate with other shocks will be similar. I may end up trying some different spring rates, but this seemed like a good starting point.
Third advantage, and this is less than I thought, is weight. All of the stock torsion bar stuff including keys, crossmember, bars, shocks, and bolts weighs 71lbs. My shocks with my brackets (upper and lowers), and 6" 2.5" springs and limiting straps weigh 15lbs each. So total weight savings is only 40lbs, but it IS weight savings with a much better riding and handling front end.
The only real disadvantage I can think of is it costs money and you maybe have to modify your frame (drilling). Both of which are par for the course in this hobby it seems.
Lower Mount
I drew these up in AutoCAD and had them laser cut from 3/8" steel and powdercoated them a matte black. They are doweled and have been professional welded. It is the male end of the dowel into the sides supporting the weight, not the weld, so there is no need for a lot of welding. In addition, the bolts holding these to the frame (the lower shock bolt hole) and new coilover bolt hold them together. These are not going anywhere. The need for these is because the lower mount on the 1500 4wd LCA is a male-style mount. All aftermarket coilovers that I have found also have a male style mount, so the issue is trying to hook up two male style mounts togther. These brackets sit on top of the shock mount and prevent the coilover lower mount from rotating on the LCA.
The included hardware is all grade 8 stuff. Either bolt makes a good mounting location for limiting straps if you plan on going that route. There is plenty of clearance for the cv shaft and everything else. This is literally a slide-over and bolt in place of the shock deal.
The width inside is roughly 1 3/8". My QA1 shocks have a lower mount thickness with the bearing of approximately 1". To prevent it from sliding around I use a pair of these spacers: http://www.summitracing.com/parts/aaf-all18571. I was not sure if different coilovers have different mounting widths, but these should be wide enough to accommodate anything. These spacers are not included with my kit.
Upper Reinforcement
Similar to the lower mounts, these are laser cut 3/8" steel that have been professionally welded and powdercoated. These are optional for the coilover swap and do require some drilling or welding. I say they are optional because guys have not reinforced the top mount and been fine. However, many feel this is not safe because the shock hoop was not designed with carrying the full weight of the vehicle in mind, especially over harsh terrain if thats your thing. These are side dependent and work by sitting up inside the factory upper shock mount and use two 1/2" grade 8 bolts through the frame to secure it. I call this a reinforcement mount because it is reinforcing the mount that is there, not just carrying the full weight by itself. When you drill the holes for these, I recommend bolting them through the top to ensure they fit tight to the frame before you start drilling. Remember when drilling, use lots of oil and go slow with moderate pressure. Cobalt drill bits are great for drilling steel.
The passenger side is relatively easy to get to, but because of the differences in the frame, the driver side is a bit hard and needs to be reached by using a wrench under the truck. This is kind of a pain...ok its a pain in the ass since there is not a lot of room, but can be done. I used the trick of using a piece of tape to hold the nut and washer to the wrench as I put it up there. The upper mount works well as an anchoring point for limiting straps as well, although this is more difficult on the driver side because of where the holes are in relation to the spring. This may not be an issue on other setups but it was on mine. The other option than drilling through the frame is to simply weld them in place and not use the bolts. The coating will need to be stripped on both the mounts and the frame to make sure you get a good weld. I bolted mine on, but if you have a good welder or know a guy, go for it. A note on bolting them in, do not overtighten these. The frame bends rather easily, you just want to take up the slack in the bolt. You can easily overtighten and bend the frame, so be mindful.
I you ever decide to convert back to torsion bars (dont know why you would), you can leave the top mount in place, the factory shock will still fit fine. So if you want to weld to the frame, this is not something that is completely irreversible.
Adapting The Top Mount
Most coilovers have an eyelet upper mount. If you do not want to change this, you need to use a shock adapter like this one: http://www.summitracing.com/parts/exp-690001. I used this exact one. The inner width is roughly 1.5" and similar to the bottoms the mount on my QA1s is 1", so I used these spacers to take up the slack: http://www.summitracing.com/parts/aaf-all18572.
While we are on this, if you use this mount, it will move the mounting point 1.5" down. This is not a big deal for lifted or leveled trucks, but for guys wanting to go really low you may want to try the second method. QA1 offers a conversion kit to convert the bearing style upper mount to a stud style: http://www.summitracing.com/parts/hal-ss110sdm. I have not used these, but they negate the need for the shock adapter and should allow the use of a longer shock or to go lower with the same size shock than the procomp adapters. I probably would have gone this route if I had known about them before I bought the procomp adapters.
My kit does not include any of these options, only the upper mounts with bolts to bolt to the frame.
If someone decideds to do these top mount stud conversion instead of the procomp adapter, please take some time to measure it as im curious to how much it changes the mounting height.
Why Coilovers?
There are several advantages to coil overs from torsion bars. The biggest one is they ride much, much better, and depending on what shocks and springs you use can have many different ride settings for many different conditions. Torsion bars, on the other hand, leave you pretty much stuck and only able to adjust shock dampening rates and not the spring rate itself. Many 4wd guys crank or decrank the bars to adjust ride height (yes this applies both to lifted and lowered guys), and this changes the ride drastically.
The torsion bar setups are basically meant to ride on the bump stops or slightly above them. On lifted setups when you crank the bars the ride is usually the biggest complaint since the bump stop is so far away its not used. On lowered setups its basically the same just the opposite direction and you are constantly riding on the bump stops even after trimming them.
Second advantage is going to be the huge selection of shocks and springs available in the aftermarket. I use QA1 shocks and hyperco springs, however king, fox, qa1, and whoever else make coilovers can be used. Spring wise, hyperco seems to offer the biggest range in lengths and spring rates that I could find, and they are well priced. I used 1000lb springs with qa1 ds301 shocks. The spring sounds stiff but these shocks only have 2.5" of travel, and my truck weighs approximately 1250lb of sprung weight so in order to get in the middle of the shock travel 1250/1.25 = 1000lb. To calculate with other shocks will be similar. I may end up trying some different spring rates, but this seemed like a good starting point.
Third advantage, and this is less than I thought, is weight. All of the stock torsion bar stuff including keys, crossmember, bars, shocks, and bolts weighs 71lbs. My shocks with my brackets (upper and lowers), and 6" 2.5" springs and limiting straps weigh 15lbs each. So total weight savings is only 40lbs, but it IS weight savings with a much better riding and handling front end.
The only real disadvantage I can think of is it costs money and you maybe have to modify your frame (drilling). Both of which are par for the course in this hobby it seems.
Lower Mount
I drew these up in AutoCAD and had them laser cut from 3/8" steel and powdercoated them a matte black. They are doweled and have been professional welded. It is the male end of the dowel into the sides supporting the weight, not the weld, so there is no need for a lot of welding. In addition, the bolts holding these to the frame (the lower shock bolt hole) and new coilover bolt hold them together. These are not going anywhere. The need for these is because the lower mount on the 1500 4wd LCA is a male-style mount. All aftermarket coilovers that I have found also have a male style mount, so the issue is trying to hook up two male style mounts togther. These brackets sit on top of the shock mount and prevent the coilover lower mount from rotating on the LCA.
The included hardware is all grade 8 stuff. Either bolt makes a good mounting location for limiting straps if you plan on going that route. There is plenty of clearance for the cv shaft and everything else. This is literally a slide-over and bolt in place of the shock deal.
The width inside is roughly 1 3/8". My QA1 shocks have a lower mount thickness with the bearing of approximately 1". To prevent it from sliding around I use a pair of these spacers: http://www.summitracing.com/parts/aaf-all18571. I was not sure if different coilovers have different mounting widths, but these should be wide enough to accommodate anything. These spacers are not included with my kit.
Upper Reinforcement
Similar to the lower mounts, these are laser cut 3/8" steel that have been professionally welded and powdercoated. These are optional for the coilover swap and do require some drilling or welding. I say they are optional because guys have not reinforced the top mount and been fine. However, many feel this is not safe because the shock hoop was not designed with carrying the full weight of the vehicle in mind, especially over harsh terrain if thats your thing. These are side dependent and work by sitting up inside the factory upper shock mount and use two 1/2" grade 8 bolts through the frame to secure it. I call this a reinforcement mount because it is reinforcing the mount that is there, not just carrying the full weight by itself. When you drill the holes for these, I recommend bolting them through the top to ensure they fit tight to the frame before you start drilling. Remember when drilling, use lots of oil and go slow with moderate pressure. Cobalt drill bits are great for drilling steel.
The passenger side is relatively easy to get to, but because of the differences in the frame, the driver side is a bit hard and needs to be reached by using a wrench under the truck. This is kind of a pain...ok its a pain in the ass since there is not a lot of room, but can be done. I used the trick of using a piece of tape to hold the nut and washer to the wrench as I put it up there. The upper mount works well as an anchoring point for limiting straps as well, although this is more difficult on the driver side because of where the holes are in relation to the spring. This may not be an issue on other setups but it was on mine. The other option than drilling through the frame is to simply weld them in place and not use the bolts. The coating will need to be stripped on both the mounts and the frame to make sure you get a good weld. I bolted mine on, but if you have a good welder or know a guy, go for it. A note on bolting them in, do not overtighten these. The frame bends rather easily, you just want to take up the slack in the bolt. You can easily overtighten and bend the frame, so be mindful.
I you ever decide to convert back to torsion bars (dont know why you would), you can leave the top mount in place, the factory shock will still fit fine. So if you want to weld to the frame, this is not something that is completely irreversible.
Adapting The Top Mount
Most coilovers have an eyelet upper mount. If you do not want to change this, you need to use a shock adapter like this one: http://www.summitracing.com/parts/exp-690001. I used this exact one. The inner width is roughly 1.5" and similar to the bottoms the mount on my QA1s is 1", so I used these spacers to take up the slack: http://www.summitracing.com/parts/aaf-all18572.
While we are on this, if you use this mount, it will move the mounting point 1.5" down. This is not a big deal for lifted or leveled trucks, but for guys wanting to go really low you may want to try the second method. QA1 offers a conversion kit to convert the bearing style upper mount to a stud style: http://www.summitracing.com/parts/hal-ss110sdm. I have not used these, but they negate the need for the shock adapter and should allow the use of a longer shock or to go lower with the same size shock than the procomp adapters. I probably would have gone this route if I had known about them before I bought the procomp adapters.
My kit does not include any of these options, only the upper mounts with bolts to bolt to the frame.
If someone decideds to do these top mount stud conversion instead of the procomp adapter, please take some time to measure it as im curious to how much it changes the mounting height.
