Confused picking Moog spring

[mr_senior]

Thanks for asking! We fought the insurance agency for a year and finally got a settlement and bought it back from them. We did pick up a new frame and a 6.0 L LS engine but that's it, it's been in storgae since. My son took the settlement and bought a beater '84 S10 and built a healthy 355 SBC and T-56 6 speed, 18" wheels and decent tires and a dropped suspension. It's almost ready to get back on the road. That'll be his driver and then he wants to rebuild Coppertop the right way instead of just getting it back on the road. I've been working on designing some of my own parts that we'll incorporate into Copper's rebuild too so timing is coming together. I bought another G-body, an '86 Bonneville that'll also get a pro touring build. I plan to start a build thread soon, as soon as I get the garage back I'll go full bore on it. ... Sorry to hijack the thread a little Mr Senior. 🙂

My son's S10...

No worries

 

[fleming442]

I have 5662s on a v6. I don't necessarily agree with the sentiments about drop spindles. For me, on a daily driver, the benefits outweigh the negatives. Yes, the stock camber curve sucks, but that's under full compression. So, if the spring is stiff enough, you don't get into the "bad" part of the curve very often, and retain full suspension travel for when it's needed instead of bottoming out on bumpstops. In the end, it depends on what kind of ride you want, how you drive the car, and how much money you want to spend. You could always just go full-ghetto and torch the springs to drop it.

 

[ssn696]

Since it may carry a payload in the future, you might supplement the rear springs with air bags or air shocks for when it is loaded. (I assume air shocks are still a thing.)

 

[SRD art]

Thanks for taking the time to write that. Definitely shined a little light on the subject. Glad you brought up compression weight. Seeing how it's an elco and it does get used as a truck from time to time would a heavier rear spring be a smart idea to help with cargo load. Suspension has always been my automotive weakness lol. I'm also adding sway bars to my research list

My pleasure. Having worked for one of those main stream Pro Touring suspension companies plus trial and error with my cars has taught me a lot. I'm always open to share that knowledge when I can.

To answer your Elco question, yes it would be nice to have extra rate in the rear to hold up loads better. But consider how much you drive loaded compared to unloaded. If you run a really heavy spring to let's say make it equal to a 1/2 ton truck, then it'll probably ride pretty stiff unless you're loaded. If you only load it up once in a while then it doesn't seem like a very good trade off, and maybe an air helper spring or bag might be a better idea for those occasional loads. I had Lakewood Drag Bags on my wagon to help tune my Eibach rear springs and when I had some weight in the back I pumped them up and ran them basically flat on normal daily driving. Now with the adjustable shocks I can control the ride by cranking up the compression to handle the weight a bit, but it doesn't do much for maintaining ride height with a load.

To create a predictable, balanced handling car front and rear spring rate has to be cohesive and there is a point of good balance. Too much front spring rate and the front will push or "under steer", i.e. in a hard corner the car will feel like it's still going kinda straight even though you're turning the wheels. The factory builds under steer into the car maybe because it's easier for most folks to simply slow down to get the car back under control rather than try to correct an over steer issue. Oversteer is a result of too much rear spring rate and causes the front to dig in and the back to slide out. Imagine Granny driving her 79 Malibu in the rain and if the car has over steer she's drifting around corners. As much as I'd like to see that I think it would be more akin to causing cardiac arrest than Granny adding Hoonigan stickers to her car. With that in mind we can focus on balancing the rear with the front better to find that balance and tune out the under steer.

With my car and it's heavy spring rate I tried 3 different rear sway bars and couldn't get rid of the over steer, and the car's butt would want to slide sideways accelerating out of corners. I finally removed the rear sway bar altogether and the car was suddenly balanced and predictable, and I could fine tune it through adjusting the coilovers. In your case, a heavy rear spring rate to hold a heavy load will need to be balanced with a heavy front spring rate, and at some point you have a dump truck ride instead of an El Camino. That's why air assist is nice, you only have it when you need it.

 

[SRD art]

I have 5662s on a v6. I don't necessarily agree with the sentiments about drop spindles. For me, on a daily driver, the benefits outweigh the negatives. Yes, the stock camber curve sucks, but that's under full compression. So, if the spring is stiff enough, you don't get into the "bad" part of the curve very often, and retain full suspension travel for when it's needed instead of bottoming out on bumpstops. In the end, it depends on what kind of ride you want, how you drive the car, and how much money you want to spend. You could always just go full-ghetto and torch the springs to drop it.

You bring up a really good point. With Pumkinator I'm all about autocross performance, so I'd personally steer clear from a basic drop spindle for that car. However on my '88 S10 Blazer I bought the full Bell Tech drop including drop spindles that maintain factory geometry, simply for a cool looking low cruiser. You really have to decide what you want out of the car, and build it accordingly, both my G-body and my S10 have pros and cons to their set up but do what they need to according to their use. Either way, in my opinion, no matter how you do it, a lowered car always at least looks cool. 😀

 

[mr_senior]

Base on what I've understood before selecting a spring rate there a checklist I should do.
1: I need to determine how the car is going to be used "primarily"
2: budget
3: current weight distribution.
4: body roll is deduced more effectively with sway bars and bushing vs springs

I found a member on here that weight his Elko and got these numbers.
Total = 3440
Front = 2010
Rear = 1440
I went head and lookup his current build and it is pretty standard as far as a cast-iron bottom, aluminum heads, headers, AC, full interior, 8.8 rear-end,

Correct me if I'm wrong. Any spring with an advertised compression rate higher than 2010 in the front would be felt as " stiff " and under 2010 would be felt soft. Now, I know this is an extreme oversimplification. My goal is to determine a rough point of reference When selecting spring rates.

 

[fleming442]

Moog springs are $45 from rockauto- won't break the budget.
Depending on your needs for driving style, stiffer springs need less bar diameter. I have to say that I lucked up with the current combination. It's rock steady up to and over 100mph. I still want to put the 707lb springs up front, but haven't driven it with the rear bar installed. Baby steps.....

 

[mr_senior]

Moog is definitely the way to go. especially, when you're experimenting with different combinations and ride height.

 

[Supercharged111]

Spring rate is different than wheel rate. On a car like the G body, the wheel rate is going to be around 2:1, maybe worse. This is because the springs act on the inboard part of the arm, not the knuckle like on a Mac strut car which is close to 1:1. So your 700# springs end up around 350# at the wheel, so if you add 150# you'll drop closer to 1/2" than 1/4". It's all guesswork until you start measuring pickup points on the suspension.

 

[mr_senior]

Spring rate is different than wheel rate. On a car like the G body, the wheel rate is going to be around 2:1, maybe worse. This is because the springs act on the inboard part of the arm, not the knuckle like on a Mac strut car which is close to 1:1. So your 700# springs end up around 350# at the wheel, so if you add 150# you'll drop closer to 1/2" than 1/4". It's all guesswork until you start measuring pickup points on the suspension.

When you use # are you referring to lbs?