C10 coil drop vs spindle drop

[Chevy nutcase]

I'm itching to start ordering parts so I can lower my new 66. My original plan was 2 1/2 drop spindles, disk conversion, dual master cylinder and possibly a booster and 3" rear coils. Well after a bit of study I quickly realized my original wheels may not jive with a modern disk setup soooo I priced out new wheels and tires and it's a minimum $1200 tacked on to my original plan. While I was at it I priced out swapping the rear axles for 5 lug which opens up an ocean of wheel choices and woo hoo the $1200 jump is now $1800 on top of the lowering parts. This got me thinking. The truck stops fine with drums so why not just drop it front and rear using coils. Now obviously a disadvantage of this is loss on suspension travel and disks are superior in almost every way but is there a reason I'm unaware of that 99.999% of lowered trucks upgrade the front hardware to disk when lowering over using just coils? I can get my truck down where I want it for less than half of a disk and or 5 lug conversion. I'll completely replace every drum, shoe, spring, wheel cylinder, hard line and soft line and still have a lot left over for other improvements. It will be interesting to hear what you guys think

[Paul Y]

Drums work fine but do have their limitations, usually when pushed hard or poorly maintained.

If you are on a budget then stick with them, just carry out the preventative maintenance you described.

As for coils I copied Skinny G and used Moog 6454 1 ton coils trimmed to fit up front- I must admit that I am using a dropped spindle and disks but there is no reason why these won't work with a more severe cut to reduce your altitude.

Out back the coils came with the truck but think they are the jeep ones with 2" lowering blocks.

I have seen drop spindle and disk conversions with 6 stud - what is the reason you dont think these will work with your existing wheels?

Share some pictures so we can oooh and aaaaarrr over your purchase!

P.

[bigmoe]

Originally Posted by Paul Y

As for coils I copied Skinny G and used Moog 6454 1 ton coils trimmed to fit up front- I must admit that I am using a dropped spindle and disks but there is no reason why these won't work with a more severe cut to reduce your altitude.



P.

I've read the Skinny G method of using one ton front coils (trimmed) but geez that must make for a stiff ride? I put stock HD coils on front and the ride was pretty harsh (v8/auto). I ended up getting the lightest stock coil (ACDelco # 45H 2104) to use with drop spindles.

[Paul Y]

Originally Posted by bigmoe

I've read the Skinny G method of using one ton front coils (trimmed) but geez that must make for a stiff ride? I put stock HD coils on front and the ride was pretty harsh (v8/auto). I ended up getting the lightest stock coil (ACDelco # 45H 2104) to use with drop spindles.

Time will tell as Woody is still in bits but hopefully it will not be unacceptable. Sure the man himself will be along shortly to corroborate.

P.

[verdell]

I think how you intend to use the truck should be part of the determining factor in your plan to achieve your desired stance/ride height. For occasional cruising around and sticking to a budget, the drums on stock spindles will suffice. However, you can't beat the overall performance, reliability and correct geometry of drop spindles and discs though. Good front suspension parts, shocks and sway bar up front combined with upgraded brakes does wonders for these old trucks. The brakes and front suspension was the very first thing I addressed when building my C10s..

[Chevy nutcase]

Thanks everyone for the insight. I know the limitations of drum brakes and the advantages of disk brakes and that was my original plan all along and I was prepared to pay for the upgrade but the front wheels accepting the new setup is so unknown. My fear is getting the kit with drop spindles and 6 lug rotors, if they fit, fantastic, if not I'm stuck waiting for tires and rims from a limited selection. I could then get 5 lug rotors and new axles but that in total would be a husky chunk of change when all is said and done. Again not a cheapskate here but theres other things I'd like to be able to afford for this like a new back bumper, power steering and eventually a T5 transmission. I've looked for people parting out a 71 or 72 that has a 5 lug rear diff that could be a direct bolt on swap after rebuilding the brakes of course but I have yet to find one. Here's a few pics if the thing that's been occupying my thoughts lately

[curvedglass]

I used CPP front disc kit with stock rear drums. CPP power brake booster with included proportioning valve. CPP 2 1/2 spindle and a 1" spring up front and 1 1/2 inch blocks in the rear. I am running 8" 80's 4x4 wheels (6 lug) 235-70-15 tires fit just fine.

Literally the first day after the upgrades I had to jam on the brakes for deer. Discs are worth every penny. No pulling or fade. If you plan to drive the truck in todays traffic (texters etc) they are a must.

[LostMy65]

Beautiful truck!

[EricS76]

Just cut your stock front coils and it’ll cost you $0.00.

[Chevy nutcase]

Originally Posted by EricS76

Just cut your stock front coils and it’ll cost you $0.00.

�� that's a fantastic idea and I feel stupid not thinking of it. My only question would be is how much removed equals how much drop? For example 1 complete twist equals 1" ⬇️? Another question is the spring rate different from lowered coils? Thank you for suggesting that

[SkinnyG]

Originally Posted by Chevy nutcase

how much removed equals how much drop?

Roughly one coil is 2".

Cut the bottom of the coil spring NOT the top - the top needs to secure itself properly, and if you cut that off it's harder to do so.

As you go lower, you really need to go stiffer or it will bottom out too easy. Try your stock springs and see if you like it. My squarebody had stock springs cut 3/4 of a coil (with 3" spindles), and then 1-ton springs with about a coil and a quarter removed (stiffer springs need more coils cut).

Good luck. And report back!!

[EricS76]

Originally Posted by Chevy nutcase

�� that's a fantastic idea and I feel stupid not thinking of it. My only question would be is how much removed equals how much drop? For example 1 complete twist equals 1" ⬇️? Another question is the spring rate different from lowered coils? Thank you for suggesting that

I cut one complete coil out and it was just a little less than 2” of drop when I put it all back together. As for different spring rate, I don’t know. Mine rides about the same with the coil cut out.

[Chevy nutcase]

I thank everyone for their input on this matter. I wish I had parts ordered a week ago but I like to get a certain amount of ducks in a row before I pull a trigger this big. Looks like I'll be cutting the front coils and replacing the other stuff. I'll absolutely let you guys know when parts start flying

[AcampoDave]

Nice truck you got there.....I too didn't want to invest big time money on a mostly stock truck which is used around town and on open roads. I redid my drum brakes and split the system to dual reservoir M/C. Then I installed a 2/4 coil drop spring kit that came with shorter shocks, shock relocation brackets, and an adjustable panhard bar. The ride is fine, it only hits the snubbers on big bumps and if I nail the brakes the rear wheels lock up. It's a longbed too. Here's how it sits on 225/35/15 tires and stock wheels....(It's got a barely perceptible rake when you can get it on level ground.)

[Chevy nutcase]

Originally Posted by AcampoDave

Nice truck you got there.....I too didn't want to invest big time money on a mostly stock truck which is used around town and on open roads. I redid my drum brakes and split the system to dual reservoir M/C. Then I installed a 2/4 coil drop spring kit that came with shorter shocks, shock relocation brackets, and an adjustable panhard bar. The ride is fine, it only hits the snubbers on big bumps and if I nail the brakes the rear wheels lock up. It's a longbed too. Here's how it sits on 225/35/15 tires and stock wheels....(It's got a barely perceptible rake when you can get it on level ground.)

That's a beautiful truck and sitting exactly how I picture mine. You also did to yours what will likely be done to mine since another board member Erics76 suggested cutting my front coils. Besides that I need 3" rear coils a dual reservoir master cylinder, adjustable track bar and rebuild all 4 corners of the brake system "if necessary " and bada boom vroom vroom

[AcampoDave]

On my shortbed I dropped the rear with a 2" spring and a 1" axle block. Obviously, this did affect the shock angle and travel although not severely. (The spring changed the shock but the block didn't.) Anyhow....someone posted a mod to the upper shock mount where you drill a new hole higher and in a more direct line to the bottom. I did it and it worked great. I searched for that thread but can't find it. This pic will help explain, basically you are redrilling the hole in the red area and cutting it off at the yellow line. This of course only approximates the info given in the actual thread but hopefully someone else knows where it is and will drop in and link it up
Edit: I would've used a drill press if I had one but managed it with a handheld placing the bracket in a vise.

[AcampoDave]

Hey, I found it. I didn't mess with the lower mounts, only the top because 63-'66 are different than 67-67 on the bottom. http://67-72chevytrucks.com/vboard/s...d.php?t=359399

[Chevy nutcase]

Originally Posted by AcampoDave

Hey, I found it. I didn't mess with the lower mounts, only the top because 63-'66 are different than 67-67 on the bottom. http://67-72chevytrucks.com/vboard/s...d.php?t=359399

That's awesome. Thank you for finding this. Like you I think I could get away with only modifying the upper mounts since I'm only dropping the rear 3". 4 or 5 would probably need lowers changed as well

[SCOTI]

Originally Posted by Chevy nutcase

That's awesome. Thank you for finding this. Like you I think I could get away with only modifying the upper mounts since I'm only dropping the rear 3". 4 or 5 would probably need lowers changed as well

Since I'm the guy that originally posted the info, yes, you can just do the upper mount mod but travel gains won't be as much. As @Paul_Y suggested, the outboard mounting offers better results.

As for just cutting coils.... Yes, it can work; but it def will leave some ride quality on the table. For a part time rig & a temporary set-up it gets the truck closer to what you want while saving for the better braking set-up.

The issue you mention (6-lug discs working w/your OE 6-lug wheels)? There will be interference as the barrel of a drum brake wheel was different vs when disc brake wheels came into play. There will be caliper clearance issues. Options are to find/purchase just some new front aftermarket steel wheels in the same size. That allows the front tires to swap over so no additional costs & they'll work w/the disc set-up. With hubcaps on, you really won't notice a difference.

My disc swap combo was typically dropped disc brake spindles & one coil off the original springs (if I liked the ride quality of the un-cut springs & there was no excessive lean). If you cut the coils beyond that 1-coil, that's where you'll start to muddy the waters.

The original springs usually don't have enough spring rate when the springs height is reduced drastically (say 2-coils removed). My research stated that removing 1-coil was the equivalent of increasing the spring rate by </= 20%. The more you cut, the more the rate increases but it may/may-not be enough of an increase for the reduction in travel.

If the original spring rate is 700# & 2 coils are removed w/a rate increase of ~20% you would be around 840#. You might need 980# for that height of spring to yield a ride that's not constantly compressing to the point of contact. This is where the combo's provided w/the kits have some value (unless they're not doing the homework & just tossing parts together). The longer the coil, the better the ride quality.

[Paul Y]

You could always look at mounting the rear shocks outside the chassis like FrizzleFry did. I copied his methodology on my truck when I first did the suspension upgrades and it made a noticeable difference.

Not his post but his pictures.

http://67-72chevytrucks.com/vboard/s...d.php?t=612934

P. D

[AcampoDave]

SCOTI that was a great write up on the shock brackets. After I did the top, a tape measure revealed the installed shock length to be unchanged, simply because the shock became straighter and the distance between the top and bottom shortened. But then the higher mounting point restored it to its former length. The real benefit to me was restoring the shock to its original angle. What I've wondered for some time however is this; if the shock set up on the 60-62 was superior to 63-66, why did Chevy change it?

[verdell]

Originally Posted by AcampoDave

SCOTI that was a great write up on the shock brackets. After I did the top, a tape measure revealed the installed shock length to be unchanged, simply because the shock became straighter and the distance between the top and bottom shortened. But then the higher mounting point restored it to its former length. The real benefit to me was restoring the shock to its original angle. What I've wondered for some time however is this; if the shock set up on the 60-62 was superior to 63-66, why did Chevy change it?

As a 60-62 owner, I've always wondered the same thing. Especially with companies like No Limit Engineering selling shock mount kits that replicate the 60-62 rear set up.

[SCOTI]

Originally Posted by AcampoDave

SCOTI that was a great write up on the shock brackets. After I did the top, a tape measure revealed the installed shock length to be unchanged, simply because the shock became straighter and the distance between the top and bottom shortened. But then the higher mounting point restored it to its former length. The real benefit to me was restoring the shock to its original angle. What I've wondered for some time however is this; if the shock set up on the 60-62 was superior to 63-66, why did Chevy change it?

My guess it's relayed to the actual change w/the frame. Eliminating the x-center & revision @ the rear x-members allowed incorporating the shocks there. That being said, the farther out the springs & shocks are, the more stable the ride will be.

[Chevy Fleetside]

http://67-72chevytrucks.com/vboard/s...d.php?t=727826 This is what I did for the disc brake swap. I basically put my own together with parts from rockauto.com I have since lowered it with 2 1/2 drop spindles and 3" drop springs in the back with 235/75 r15 tires all around. I do have 5 lug up front and 6 in the rear but will change that soon. I have 6 lug disc's waiting for me to install after I make sure my wheels fit. Too bad your that far away from here. I have a 72 rear end I might want to part with and also a complete 73 front suspension. They are for another truck I have which will probably not get built now.

[SCOTI]

Originally Posted by Chevy Fleetside

http://67-72chevytrucks.com/vboard/s...d.php?t=727826 This is what I did for the disc brake swap. I basically put my own together with parts from rockauto.com I have since lowered it with 2 1/2 drop spindles and 3" drop springs in the back with 235/75 r15 tires all around. I do have 5 lug up front and 6 in the rear but will change that soon. I have 6 lug disc's waiting for me to install after I make sure my wheels fit. Too bad your that far away from here. I have a 72 rear end I might want to part with and also a complete 73 front suspension. They are for another truck I have which will probably not get built now.

When I first lowered my 68, I did the same thing. Five lug OE disc brake front wheels & 6-lug OE rears. With the poverty caps on, you didn't know they weren't the same.