Not sure how you can't find a savings, because the savings is dramatic.
RMS Alterkation w/engine mounts and without brakes - $4,995
RMS Street Lynx - $1,995
Total: $6,990 (keep in mind this doesn't include installing the street lynx, which takes welding)
My Duster
Front:
1.12" torsion bars from Firm Feel: $355
BAC UCA's:$395
Howe Racing upper ball joints: $130
Moog lower ball joints:$80
QA1 LCA's: $395
Hotchkis Shocks: $475
Hellwig 55905 front bar: $175
Flaming River 16:1 steering box: $610
QA1 tie rod sleeves: $50
Moog tie rods (all): $60
Moog pitman and idler arms: $80
Adjustable PST strut rods:$300
Rear:
Hellwig 6908 rear bar: $180 (this is the Ebody bar I run with my B-body rear axle)
AFCO 20231M springs: $320
AFCO leaf spring sliders: $200
Dr. Diff 1/2" spring offset:$150
Leaf spring perches: $15
Front suspension: 3,105
Rear suspension total: 865
Total: $3,970
So, my parts total is $3K cheaper than just the parts for the RMS alterkation and street lynx. In fact, my parts total is $1k less than just the Alterkation, and I did the whole car. My prices are mostly all Summit racing. Firm Feel, Bergman Autocraft, PST, and SD truck springs (sway bars) were also used.
Obviously, that's not the total cost. Brakes aren't included, neither is any of the chassis stiffening or wheels and tires. But that cost is the same regardless of which system you use, and the prices for the RMS conversions doesn't include any of that either. And you would still need all of it. And I included all the parts to make everything new, ie, pitman, idler, tie rod ends, ball joints etc, so that everything replaced by the RMS components would also be new on the torsion bar/leaf car. Realistically, you could save A LOT of money by not using tubular UCA's and LCA's, and just using offset UCA bushings (moog 7103) and boxing your stock LCA's and replacing the LCA bushings. Like about $700. And if you kept the stock steering you save $600. Or add a Howe steering quickner to the stock steering and still get a ratio improvement, the 1.5:1 is only $90. Drop the leaf spring sliders and save $200. Another $150 for the 1/2" spring offset. Not necessary, but without a mini-tub it gets you the same tire clearance as you'd get with the 4-link.
I also used all BRAND NEW prices. I didn't spend that much. I bought my Flaming River 16:1 manual box for $300, new in the box but secondhand. My strut rods were made by maddart, and I paid much less for them. But they're not available anymore so I included the new PST price. Maybe I forgot a bushing or two, but by all means, add them to the total. You won't get anywhere near the $7k you need for the RMS conversion, and that's just parts.
