03TKMRacing
New Member
I’m definitely far into the project to be posting about the car but I have a 1971 Dodge Demon that I am swapping a 6.7 Cummins from an 09 Ram 3500.
Originally the car was a slant six 225 with the 904 and 7 1/4. I thought of turboing the slant six, ls swap, and even a 2j swap but ultimately I wanted a Cummins. I started with a 12v block and got the engine mounts in, oil pan cut, trans mounted, radiator moved in front of the support but the 12v just didn’t seem right. I always wanted to do a 6.7 build but they were always too pricey. That was until I found a great deal on an engine from a wrecked truck with an upgraded turbo and was meticulously maintained.
I then found out that the 6.7s are a lot bigger everywhere than a 12v. The oil pan is wider and the crank/rods dip below the bottom of the block and the valve cover assembly is a lot taller too. Surprisingly when I remade the engine mounts I was able to get the engine to sit lower and further back this time. I clearanced the floorboard crossmember to fit the large 47re and made a bolt in tranny crossmember that also works as crossbracing to triangulate the subframe connectors I made.
For suspension I installed all the QA1 goodies; upper/lower control arms, strut rods, k member. I plan on getting a large sway bar and some shocks other than KYBs. For torsion bars I got 1.20” from SwayAway that are roughly 480inlbs spring rate. For steering I have a borgeson quick ratio ps box and I’m going to make my own center link/tie rods to clear the oil pan but keep the correct geometry.
The rearend I will eventually minitub and swap to a 9” (I know it’s not an 8 3/4 or a Dana 60 but I’m going for ultimate strength and really tall gears). For now it’s just got the 7 1/4 so I can get the engine and trans tuning good for easy driving and make it a solid cruiser.
There’s honestly a ton I’ve done to the car and I can’t think of everything off the top of my head but I plan on posting about it more often now so hopefully I’ll remember more later.
Originally the car was a slant six 225 with the 904 and 7 1/4. I thought of turboing the slant six, ls swap, and even a 2j swap but ultimately I wanted a Cummins. I started with a 12v block and got the engine mounts in, oil pan cut, trans mounted, radiator moved in front of the support but the 12v just didn’t seem right. I always wanted to do a 6.7 build but they were always too pricey. That was until I found a great deal on an engine from a wrecked truck with an upgraded turbo and was meticulously maintained.
I then found out that the 6.7s are a lot bigger everywhere than a 12v. The oil pan is wider and the crank/rods dip below the bottom of the block and the valve cover assembly is a lot taller too. Surprisingly when I remade the engine mounts I was able to get the engine to sit lower and further back this time. I clearanced the floorboard crossmember to fit the large 47re and made a bolt in tranny crossmember that also works as crossbracing to triangulate the subframe connectors I made.
For suspension I installed all the QA1 goodies; upper/lower control arms, strut rods, k member. I plan on getting a large sway bar and some shocks other than KYBs. For torsion bars I got 1.20” from SwayAway that are roughly 480inlbs spring rate. For steering I have a borgeson quick ratio ps box and I’m going to make my own center link/tie rods to clear the oil pan but keep the correct geometry.
The rearend I will eventually minitub and swap to a 9” (I know it’s not an 8 3/4 or a Dana 60 but I’m going for ultimate strength and really tall gears). For now it’s just got the 7 1/4 so I can get the engine and trans tuning good for easy driving and make it a solid cruiser.
There’s honestly a ton I’ve done to the car and I can’t think of everything off the top of my head but I plan on posting about it more often now so hopefully I’ll remember more later.