Project: Recycle

[aggie91]

Looks good Scoti. Would you mind sharing the specs you used to get your shocks? Part numbers, extended length, compressed length, etc? I am planning something similar on my next project (1975 C10) but want to work with parts I already have instead of buying a whole next coil over package deal...

[SCOTI]

Originally Posted by aggie91

Looks good Scoti. Would you mind sharing the specs you used to get your shocks? Part numbers, extended length, compressed length, etc? I am planning something similar on my next project (1975 C10) but want to work with parts I already have instead of buying a whole next coil over package deal...

As for the specs.… I based things off of what's currently sold via the aftermarket.

I studied some generic weight break-downs for choosing a spring rate but that just gets me started. I understand I'll possibly need to make changes as I don't have scales so I'm guessing on some criteria for the calculations.

Since the manufacturers that offer bolt-in C/O systems base things off of the original build platform, one can use their set-up. But, Porterbuilt didn't offer a bolt-in alternative for my DM's upper mount (it is a pre-'07 version) so I was on my own as there was nothing available (he did try to help). I did get an offer for an older DM specific C/O bracket that possibly would have worked but it would have required that 3.6 stroke shock & I had already made templets for my own. I pressed forward...

Anything based on the original platform is limited to that platform when building their bolt-on kits or the costs go higher & closer to complete replacement x-members which might hurt sales. Since I wasn't limited to any original platform, I looked @ what builders used when fabbing one-off pieces as well as lots of suspension/shock/spring research. One thing I know is a longer spring/shock combo helps ride quality as long as you have room for the travel. Using that info & researching what is commonly used in a stock chassis C10 C/O set-up, I just looked to see how much I could increase the shock length. I know PB & Ridetech use a 3.6 stroke shock up front so I went from there & chose a 5" stroke shock. Based off of shock stroke, they recommend certain length springs. I did calcs & chose to start w/a 750# spring rate up front & go from there once I'm no longer guessing on certain factors.

But, I didn't just drop bucks on some C/O's only hoping they would work.... I constantly plan/try to have a Plan-B. Ironically, the C/O's shock length I chose are what PB & Ridetech both spec for the rear of their C10 kits AND it's also the same length for the Ridetech G-body rear kit. Since I based my rear shock set-up off of a G-body w/the specific idea of possibly going to a coil-over in the future, any G-body spec'd C/O would be a possible candidate AND since I mess w/G-body's, I can always utilize them there if I run into an impass on using them for the 64.

Ridetech lists the shock as a 5.2 stroke:14.5 @ ride height; 11.25" compressed; 16.75" extended. They call for a 12" spring but there are variances & a 10" seemed like a good choice (their C10 kit calls for an 8" spring w/a 1.6" shorter shock). As for the spring rate.... Weights, angles, & pivot dimensions are required to narrow it down. From the kits I noted, my shock is slightly more upright vs theirs & my dimensions are shorter (A-arm pivot to BJ C/L; A-arm pivot to shock bottom C/L). They spec an 800# & I'm trying a 750# which also happens to be what these came with.

The 2nd set of coils purchased are 12" 275# springs which is what the rears are spec'd for.