57 Nomad-C4-LS1 called "Ozzy"

[Custer55]

Looks good to me!! Nice to see some progress.
Brian

[rockytopper R.I.P 5-13-2017]

Whats to pick looking Great!!!!

[chevynut]

Looks great Paul. Are you planning to get it to the point of driving it before you tear it down to finish it?

I'm curious where the adjuster is on your front shocks at this point. I realize you still have fluids and a hood to bolt on, as well as glass and a bumper. Going through the spring calculations with another customer recently, we decided to have him try a 350 lb/in front spring and run it near the top of the adjustment to get a lower wheel rate and a softer ride. His 56 HT is set up just like your Nomad using QA-1 shocks.

One thing I'm lacking is actual empirical data on spring rates on finished cars. I got some from Wade and Bruce long ago but really need more to validate my spring calculator. I'm pretty comfortable with the front spring calculations, but the rear is still fuzzy. Their rear shocks were set up differently than I do them now.

[WagonCrazy]

Heading out the door for the day, but tonight i'll get the QA1 order and spring specs together and post those. Just so you know what I did as another baseline.

And yes, I''m going to get it together to drive it and work out the gremlins BEFORE I tear it all back down for paint, polishing,etc.

[WagonCrazy]

Fronts are ViKing #C218. The shock body is advertised as 10.48 max compressed (eye to eye) and 15.05 max open (eye to eye). I have 10 inch 500 pound springs on them, and I have them adjusted to the very bottom of the shock (as uncompressed as I can get them). If I adjust the spring tighter, it raises the front end. Not sure if I need to go with shorter springs or just lighter springs so i can compress them. I dont' have the bumper, hood or glass installed yet, so there will be more weight before I can get this dialed in.

Rears are ViKing #C210. The shock body is advertised as 11.57 max compressed (eye to eye) and 16.78 max open (eye to eye). I have 12 inch 400 pound springs on them. Same thing...spring is set all the way "loosest" and the rear of the Nomad sits higher than I'd like. BUT...I don't have the interior, glass, bumpers or tailgate/liftgate installed yet, so they will compress a bit more when I install all of that.

With all 4 mounted, it looks like each shock will allow about 3 inches more of compression...before the shaft "bottoms out".

[chevynut]

Paul, I think we've discussed your shocks in the past but imo the C218 is just a tad long for the front application. We set the front suspension up for around a 12" ride height length shock. At 1/2 compression yours are at 12.77".

Wade's Nomad weighed in at 1870 pounds in front and 1816 in the rear, for a total of 3686 pounds with a full tank of fuel, I believe. Yours should be a bit heavier with the AME center section that's around 70 pounds, distributed approximately evenly, perhaps a bit more in the rear.

So I estimate your front end at 1900 pounds and the rear at 1856 with no passengers.

Using those weights and your shock lengths and a 12.1" ride height length, this is what my calculations show for the front:

If the nut is at the bottom of the shock (no spring preload) the spring rate should be 489 lb/in
If the nut is 1" from the bottom of the shock the spring rate should be 367 lb/in
If the nut is 2" from the bottom of the shock the spring rate should be 294 lb/in

The reason for these low spring rates is that the spring is significantly compressed at the ~12" ride height. If you go higher than that, the spring rate will be higher.

Using the rear weight and your shock lengths and a ~13.5" ride height length, this is what my calculations show for the rear:

If the nut is at the bottom of the shock (no spring preload) the spring rate should be 667 lb/in
If the nut is 1" from the bottom of the shock the spring rate should be 508 lb/in
If the nut is 2" from the bottom of the shock the spring rate should be 410 lb/in

Again your rear shock is fairly long so it's more than 1/2 compressed at ride height. You have a lot of weight to install in the rear.

I'm much more uncertain about the rear calculations and I used a "fudge factor" off of bruce's car to "calibrate" my calculator. His shock angle in the rear was much more than I do now (he built them himself) and he was using different shocks than you are.

My standard shock recommendation is QA-1 401/402 in front with 14"/10.125" extended/compressed length. In the rear I recommend a QA-1 501/502 with a 17"/11.625" extended/compressed length. I like to run the rear springs softer so they're compressed more at ride height. A longer shock helps accomplish that.

[chevynut]

Just to be clear, when I refer to the height of the nut from the bottom of the shock, it's really the preload on the spring from it's free length with the shock fully extended. Also keep in mind that no matter where the nut is adjusted, the spring rate and the wheel rate is the same with a given spring. Wheel rate does change slightly as the shock angle changes throughout suspension travel but I only calculate it at ride height.

[WagonCrazy]

Just a quick note here to say that I haven't fallen off the earth, but have been preoccupied with a planned move across town from a tract house, to a house on 1/2 acre with room to build that nice garage I've always wanted. So I haven't done anything to the Nomad in months now, except stuff it (and everything else) into a small freestanding 2 car garage on the property and try and get moved into the house. I'll start a new post on all of that soon. Maybe by Sept I'll be back in the garage working on this Nomad build. Aargh....moving sucks. (after 24 years alot of chit needs to go...)

[chevynut]

Congrats on the new house Paul. The problem is the new shop is going to take a lot of time too . Mine was supposed to be done in 3-6 months and it ended up taking around 2 1/2 years since I was plugging away at it myself after accepting an unplanned early retirement offer. It's still not really "done" since I haven't installed any cabinets and benches or air lines yet but some day I'll do that. At least it's usable.

[WagonCrazy]

At least it's usable.

That's the first goal...