3" drop springs

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TravisB

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I have been searching all over for the best way to drop my truck and have found the endless possibilities a bit of a chore to wade through. I am thinking about using Western Chassis for the stuff to lower my truck but they have a couple options I am considering.

This drop uses 3" drop coils and the price is nice. https://westernchassisinc.com/1973-87-Chevy-GMC-C10-Lowering-Kit-Coil-Spring-Flip-Kit/

This kit comes with everything but it uses spindles and coils. https://westernchassisinc.com/1973-87-Chevy-C10-Complete-Suspension-Lowering-Kit-Spindles-Flip-Kit/

I have a few questions that maybe the experts here can answer.

  1. Will I be able to use factory shocks with the cheaper kit? It doesn't come with shocks. I expect I will need to buy extenders for the rear but I am not sure.
  2. Will the 3" drop coils ride harsh?
  3. Will I still be able to run the rally wheels with the spindles in the more expensive kit? I see a lot of talk about grinding to run 15s.
Created an account to ask these questions but it looks like there is a lot of good info here. Thanks
 

Jrgunn5150

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My personal favorite, is a dropped spindle with trimmed 3/4 ton springs to get the front down. Any more than 2" of spring drop screws with the geometry.

I think they ride and handle pretty good with a CPP 2.5" spindle, 1/2 coil cut off a 3/4 spring, and a flip kit out back.
 

TravisB

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I am considering the flip kit because I don't want to
My personal favorite, is a dropped spindle with trimmed 3/4 ton springs to get the front down. Any more than 2" of spring drop screws with the geometry.

I think they ride and handle pretty good with a CPP 2.5" spindle, 1/2 coil cut off a 3/4 spring, and a flip kit out back.

Any issues with the original wheels with that spindle?
 

Jrgunn5150

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They fit the steel hubcap wheels fine, I don't know about the Rallyes.
 

1980Spartan

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My personal favorite, is a dropped spindle with trimmed 3/4 ton springs to get the front down. Any more than 2" of spring drop screws with the geometry.

I think they ride and handle pretty good with a CPP 2.5" spindle, 1/2 coil cut off a 3/4 spring, and a flip kit out back.

Im no expert in this, so you'll have to help me out here... what about the geometry gets messed up beyond 2 inches?

My guess would have been to use a coil before a spindle, as spindles change the distance between the lower control arm and create clearance issues. Not an issue, but I'm not interested in grinding suspension components. I'd go with a larger rim to tune of whatever the spindle raise was.

Lastly, is there a reason no one really sells progressive springs for these trucks? Everything is constant. There aren't many modern performance applications that aren't progressive. Why hasn't this crept into the older models? Currently Eibach is the only progressive rate spring that claims to fit that I can find. They offer springs 1 inch to 4 inch drop! I'm a little weirded out by the 4 inch drop spring! I can't believe that would really work that well, but again, I don't know. Per your statement, you might be able to shed some light on that.

Thanks.
 

Jrgunn5150

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Im no expert in this, so you'll have to help me out here... what about the geometry gets messed up beyond 2 inches?

My guess would have been to use a coil before a spindle, as spindles change the distance between the lower control arm and create clearance issues. Not an issue, but I'm not interested in grinding suspension components. I'd go with a larger rim to tune of whatever the spindle raise was.

Lastly, is there a reason no one really sells progressive springs for these trucks? Everything is constant. There aren't many modern performance applications that aren't progressive. Why hasn't this crept into the older models? Currently Eibach is the only progressive rate spring that claims to fit that I can find. They offer springs 1 inch to 4 inch drop! I'm a little weirded out by the 4 inch drop spring! I can't believe that would really work that well, but again, I don't know. Per your statement, you might be able to shed some light on that.

Thanks.


As you shorten the springs, through whatever method you use, the angle of the control arms changes, they go further from being parallel to the ground like this =, they start tilting upwards instead, like this, /. It makes everything go all wonky-doodle when you start cornering, and one side flattens out, and the other gets even more severely tilted upwards.

I'm not sure on the second part, but I'm willing to be that a call to MOOG would find you progressive springs that fit our application. I know for a fact the Trailblazer springs fit C10's, and are available as progress rates. There probably just isn't a demand to list out an applicable spring.
 

smoothandlow84

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X2 regarldless of a 2 inch or three inch spring installed or cutting a coil, the geometry changes and a front end alignment is needed.
I always preferred a 2 inch sping paired withna 2 inch spindle for a static drop.

If you install drop spindles...they DO NOT change the alignment, only the wheel position on the suspension.

Back when my build was in the early stages, I ditched the 15" steel rally and went with 20x8 up front and 20x10 out back. I planned ahead and knew that the larger the wheel diameter, the more clearance I would have. You will run into lower control arm clearance issues if you have a 15" wheel and go with a 3 inch drop spindle.

As far as progressive rate coils, I personally never worried about that. My static drop was temporary as I ended up bagging my truck and selling off the drop coils, spindles, flip kit etc after I installed the air ride.


Sounds like you will be better off with this combo ultimately. ..


2 inch drop coils
3 inch drop spindles
stock shocks front and rear
rear axle flip kit (drops approx 5-6inches)
Rear shock extenders in order to use stock shocks (cheapest way to go unless you want to upgrade socks)
20" wheels 60 series tires max sidewall

The problems you may face with the oem raly 15"....with too tall a tire, your front end will rub the fenderwells with 3 inch drop coils...no doubt. YES the ride with a 3 inch drop coil...well....sucks. unless you live in an area with flat roads, no potholes or speedbumps you might be fine, but it is rough regardless since 3 inch coils limit the amount of spring travel in the front end.

With 3 inch drop spindles, lower control arm clearance issues (complete hacks grind the lower control arm and take away structural integrity in order to make something that doesn't fit...kinda fit).

I am NOT a fan of cutting coils EVER...another hackery. Do it right and get the right springs. People USED to do the old school cut a coil because drop coils were not on the market.

I have always suggested to keep the factory cols and replace them with the drop coil of your choice. It's easier to swap out an aftermarket coil for something different, then to chop your oem and have to scrounge through a junkyard for a replacement....or worse try to source a new oem coil
 
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1980Spartan

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As you shorten the springs, through whatever method you use, the angle of the control arms changes, they go further from being parallel to the ground like this =, they start tilting upwards instead, like this, /. It makes everything go all wonky-doodle when you start cornering, and one side flattens out, and the other gets even more severely tilted upwards.

I'm not sure on the second part, but I'm willing to be that a call to MOOG would find you progressive springs that fit our application. I know for a fact the Trailblazer springs fit C10's, and are available as progress rates. There probably just isn't a demand to list out an applicable spring.

Very cool. Thanks for the explanation. Makes sense I guess. That's why 3 and 4 inch springs are seldomly used and 2.5 and 3 inch spindles coupled with 2 inch springs are so prevalent for achieving desired drops.

As for progressive springs, thanks for the insight there. I appreciate it. These trucks generally go in straight lines. I'm sure there wasn't really a major need outside of what was already on the market.
 

idahovette

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In my experience any time you take anything apart on a front end the alignment is gonna change . Whether the ball joint stud is a little off or whatever ,I always recheck the front end. It makes a big difference that I have all my Hunter equipment from my old shop set up in my home shop, so it's not a cost just time. Anyway everything changes when you take it apart. Tires cost . One of the best ways to tell if it did change is check steering wheel position, if it's not the exact same as before it's out of alignment
 

Jrgunn5150

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I'm not using alignment interchangeably with geometery.

Yes the alignment changes when you mess with stuff.

How the suspension reacts, does not, at least not in a significant way, until you stray too far. My experience is anything over 2" drop on the spring, has the arms going uphill outwards from the frame, rather than flat, or slightly downhill as they were designed to.
 

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