Coil over shock specs?????

[jfwelding]

Ok I know that this is probably an old subject and that each rig is differnt but I'm trying to gather ideas as far valving and spring rate on coil over shocks that you guys are running. I'm mainly looking at running a pair of coil overs on my front end. My buggy is simple with a sbc, auto trans, t case on rockwell axles with 43's.
So give me your specs and opinions as to what setup might work good for my rig.

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[Technician]

You need to weigh the rig.

 

[jfwelding]

I know I really need to weigh it but if I had to guess it's about 4500 lbs total and really close to equal weight front and rear, so ball park in at 1125 lbs per corner and most of the weight is down low with axles tires and wheels. Wish I had or knew someone close with corner scales so I could get an exact weight

 

[Neal3000]

you just need your sprung weight, if you do a spring calculator using your total weight its going to tell you to get springs way to heavy.

 

[jfwelding]

I understand that I need a scale weight to really determine coil rate but I'm trying to gather information and ideas as to what has worked for others with similar rigs like spring rates and valving. I'm thinking about 175 / 200 for my springs as a starting point and then go from there. I know to run a 2" longer bottom spring helps so that's already in my design plans.

 

[Neal3000]

All you really need to do is get your shocks mounted and put one spring on, theres a formula that will give you your corner weights, then call your shock guru of choice and see what they recommend for you.

 

[zukimaster]

I bet it weighs a good bit more than 4500lb! you have over 2000lbs worth of axles and wheels and tires, it will surprise ya how fast it adds up.

 

[TBItoy]

Re: Re: Re: Coil over shock specs?????

All you really need to do is get your shocks mounted and put one spring on, theres a formula that will give you your corner weights, then call your shock guru of choice and see what they recommend for you.

X2

overall weight really isn't important at all when you are trying to get your corner weights to get springs

 

[jfwelding]

Iv talked with a couple differnt people and thank you all for the input.
This is what iv come up with so far and this is not knowing the weight of the buggy, please feel free to give your all opinions

16'' travel shocks running a 16" top spring with 18" lower spring

spring rate 175 top / 200 lower or 150 top / 175 lower

valving some where around 75 / 50

 

[TBItoy]

Re:

I would probably buy a set of 16" 150lb, set the truck on it, see how much it compresses, do math, calculate what lb lower I'd need to get a little preload and desired ride height. Then order my lower springs


Or if you could borrow some springs of known rate from someone, use them to get your baseline

 

[matth_85]

spring rate 175 top / 200 lower or 150 top / 175 lower

valving some where around 75 / 50

Rates seem awful light for a cab truck to me. That valveng is about standard and should work pretty well for the front.

 

[Neal3000]

How much shaft do you want showing at ride height?

 

[jfwelding]

The way I'm looking at setting up the coil overs with 16" shocks I can run the shaft extended out exactly half way with 8" of extension and 8" of compression. But with limiting straps and bump stops be probably more like 7" both ways

 

[jfwelding]

Rates seem awful light for a cab truck to me. That valveng is about standard and should work pretty well for the front.
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It might be low on spring rate but it's a starting point basically, I'm really trying to find someone with corner scales so I know What my weight really is

 

[Neal3000]

The way I'm looking at setting up the coil overs with 16" shocks I can run the shaft extended out exactly half way with 8" of extension and 8" of compression. But with limiting straps and bump stops be probably more like 7" both ways

I bet 150/200 would get you real close to that

 

[TBItoy]

Re: Re: Re: Coil over shock specs?????

Rates seem awful light for a cab truck to me. That valveng is about standard and should work pretty well for the front.
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It might be low on spring rate but it's a starting point basically, I'm really trying to find someone with corner scales so I know What my weight really is

Once again, I think you are getting total weight and sprung (supported by the shocks) weight confused.

It doesn't matter if you had Samurai axles and 29" tires or Rockwells and 54s, you would still need the same springs to hold your truck up at the desired shock position.

 

[jfwelding]

I know that' it's critical to have the unsprung or chassis weight to get the correct spring rate for holding up the rig but it's also good to have the total or sprung weight per corner for the rebounding and valving if I'm correct.

 

[pachary]

I bet you are just as good starting with the 150/200-225 and 70/50 valving.

I also bet most folks with corner weight still have to tweak from their starting points.

I know this for sure, the calculators will spend a lot of your time and money....

 

[Neal3000]

I know that' it's critical to have the unsprung or chassis weight to get the correct spring rate for holding up the rig but it's also good to have the total or sprung weight per corner for the rebounding and valving if I'm correct.

Not really, every rig and driver tunes a little different. Generic rockcrawling setup will be a decent starting point for him i would imagine though.

 

[Neal3000]

I'm in the process of changing my springs now, and i bet my sprung weight is pretty close to your cabtruck, i have the same drivetrain. On the front I just put on 150/200 with 1" of preload 200 psi of Nitrogen and i've got 7.75" showing at ride height, i'm looking to get down to 6ish though, so i've got a softer top spring on the way.