Make it handle

[pharmd]

Rob do you have P/N's on the AGR and Lee steering units that you would recommend for the 63-66 C-10 setup?

[Mike Bradbury]

Well I just read the entire thread cover to cover including every bodies links, now I am too tired to remember any of my questions I had from the first several pages.

The one I did have was concerning the rear sway bar, I am running custom trailing arms on a Lincoln 9". I have heard that with the trailing arm suspension the rear sway bar is not as crucial because the axle acts as the sway bar. True?

I did set the arms wide and mounted 300lb 12" springs on Bilstein coil overs behind the axle and it does ride very nice. I am still in the working out the kinks phase so I have not really opened it up yet so I do not know how it handles other than daily driving.

[robnolimit]

Welcome to the thread Mike. Hmm, no, the axle is not a sway bar.The axle and trailing arms form a triangle. If you were to grab a triangle at one of the points, it wouls be easy to 'twist' the triangle side to side, and to rotate it around the center pivit. The Pahard rod takes care of the side to side. So, it's the swaybar's job to control the roll. Sounds like a nice truck so far. I like to run soft rear springs, like 175 or 200 on a C-10, this will produce more natural body roll, but more bite. Then let the sway bar deal with the increased roll. Hope to see you at the Del Mar GoodGuys in April.

[Mike Bradbury]

Rob,
So if I am running a 1.125" in the front then a 1" in the back? My goal is not a track racer but something that will handle well on the road if I need to avoid something or someone, but that is also fun on the mountian roads.

I will be there again this year. Are you bringing the '55 to the show? My dad had a Hemi powered '56 in his younger days and would love to see it.

[robnolimit]

The 1 1/8" ft, and 1" rear is a good mild to mid match, and won't be too harsh. I like that set up on trucks that are drivin alot. some of our roads are pretty rough (or dirt) so bigger bars can take the pleasure out of driving. Yes, we'll be there with the '55, and hopefully a few more fresh builds. See you there.

[robnolimit]

PharmD, I hate to give part #'s for parts that I don't carry, in case I make a mistake. In many cases, you should go straight to the source. Lee Mfg. - 818-768-0371, in Ca., and AGR perf. - 817-626-9006, in Tx. Call and talk to them. Lee is my first choice if performance is the first priority, but the cost is higher. AGR is a very nice piece and a good price.

[tasian]

man i cant wait to see you get started on the 72' make sure to get lots of pictures lol

i was wondering other then a flip kit (already did that) what are some good changes to make on a rear with leafs?

[robnolimit]

Leafs can be set up to handle pretty good. The main thing to overcome is the spring friction. Leafs have to 'grind' on each other as the suspension moves, and that friction makes the sping act inconsistent. I typically pull all but the four longest leafs, guessing you don't haul a whole lot, to get the spring rate down. Then grind a radius on the ends of the leafs. Install teflon spring liner between each leaf, with some litheum grease, and put the spring pack back together. Then its shocks and swaybars like everbody else. The spring prep takes man hours, but doesn't cost much, and it's really worth it. Give it a try.

[Mechanic77]

Hey Rob, do you think it would be worth the effort to put weight jacks on an air bag setup? I could see it potentially giving you the option to change spring rate in effect by allowing you to adjust air pressure and then using the weight jack to put the ride height where you want it. The only problem I can see is the possibility of the bag trying to roll over without the lateral support of a normal mount (if you can understand what I'm saying). Just a thought

[skoffice]

Rob, what is your opinion on limiting straps? My friend and I were discussing the other day possibly putting them on our A-arms because the coils are so short, a guy wouldn't want the coil to come unseated in a hard dive of a turn. This is on a stock style coil front suspension with aftermarket control arms in our 60's trucks. Or would the limit strap be a bad idea and hurt the roll center if ever extended that far?
Thanks for your wealth of knowledge and information!

[tasian]

im glad to hear that i've been worryed i would have to switch to coil's in the rear to get it to handle decent the swaybars are already in the works along with a pair of KYB adjustable shocks i looked around and had a hard time finding teflon for the springs online is it something that most spring shops carry?

also i flopped the axle but i still need to c-notch the frame switch the U bolts used to mock it all up and a few other little things and was thinking about centering the wheel (its back a couple inchs in the wheel well on the long beds and shows a bit more with the axle flipped) it would only be a inch or two but i wasn't sure if it will hurt my handling? and thanks for all the info im pretty lost when it comes to the finer points of suspension

[robnolimit]

Hi, chatting from Roanoke, Va. today, it's a blustery 22 deg. Brrrrr. hey, thats life. I'll be back in sunny So. Cal. soon.

Mech77 - I get the whole idea of wieght jacks and bags, for tuning, but the fabrication difficulty makes it tough. It would be more reasonable to build your mounts a 1/2" too far apart, and then shim to tune the ride. Once your dailed, you would change much.

Skoffice - Limiting straps may be a concern if the springs are really short. This is one of the reasons that I try to keep the springs longer and drop the truck in other ways. If the truck has the right swaybars on it, the sway bar should keep enough tension on the inside spring to stop it from falling out. If needed, the shock length can be adjusted to act as the travel limiter, but again, this may limit some suspension travel, butif the spring is that short, there's no spring travel out there anyway. I would only use a limiter strap as a last resort, but if thats your only answer, it's better than the spring popping out.

Tasians - Try Detriot/Eaton spring for the liner. Also, Speedway and JC Whitney. If you flipped the axle, you'll need a bolt in C-notch for clearance. As for centering the axle, you should be able to drill holes in the axle pad and U-bolt plates to accomplish this. Just remember to shorten the drive shaft. Moving the axle forward will actually help the handling.

My new project C-10 is at the shop, and I'll get some picts up as soon as I get home.

[SBTork]

Originally Posted by robnolimit

My new project C-10 is at the shop, and I'll get some picts up as soon as I get home.

if it's going to be a build with anywhere near the quality of your ford truck build.....I can't wait...

[SCOTI]

Originally Posted by robnolimit

Leafs can be set up to handle pretty good. The main thing to overcome is the spring friction. Leafs have to 'grind' on each other as the suspension moves, and that friction makes the sping act inconsistent. I typically pull all but the four longest leafs, guessing you don't haul a whole lot, to get the spring rate down. Then grind a radius on the ends of the leafs. Install teflon spring liner between each leaf, with some litheum grease, and put the spring pack back together. Then its shocks and swaybars like everbody else. The spring prep takes man hours, but doesn't cost much, and it's really worth it. Give it a try.

'Grease' can adversely effect the spring steel of springs made post 50's era according to Detroit-Eaton spring. An alternative is graphite lube.

What about the leaf spring bushings? Wouldn't eliminating friction there make the spring work more consistently? Does anyone make Delrin bushings that would eliminate the inherent 'binding' associated w/OE type rubber and/or aftermarket poly bushings?

[Mechanic77]

What about the leaf spring bushings? Wouldn't eliminating friction there make the spring work more consistently? Does anyone make Delrin bushings that would eliminate the inherent 'binding' associated w/OE type rubber and/or aftermarket poly bushings?[/QUOTE]

Rob can correct me if I'm wrong, but I think you want to stay away from a solid type bushing on leafsprings. I'm pretty sure somebody out there makes a heim end style bushing that presses in and allows for articulation.....I'm thinking a solid bushing will cause the suspension to bind up, kind of like running polyurethane bushings in the rear trailing arms.

[SCOTI]

Originally Posted by Mechanic77

Rob can correct me if I'm wrong, but I think you want to stay away from a solid type bushing on leafsprings. I'm pretty sure somebody out there makes a heim end style bushing that presses in and allows for articulation.....I'm thinking a solid bushing will cause the suspension to bind up, kind of like running polyurethane bushings in the rear trailing arms.

Delrin bushings allow the spring ends to pivot freely (like a bearing) vs. w/binding (rubber or poly bushing compressed in place).

Delrin bushings would eliminate any deflection. But, the spring & shocks should be providing the suspension dampening, not the bushing material.

[nesox]

This post is exactly what I've needed. Thanks.

Rob,I was wondering if sectioning my stock control arms to gain improved caster would be a good idea. If so. How much back and forth respectively?

[robnolimit]

Ahhh, nice to be home, in the warm part of the country. On the delron type bushings, remember that when one side of a leaf spring goes over a bump, or compresses in a corner, the axle "tips" up on one side. So, either the spring has tp flex (twist) or the bushing does. So, if you use a bushing that won't "twist", then the spring has to twist more than it used to. This makes the spring a bit stiffer. Sperical bearings are the smoothest and have the least bind, but the ride is harsh. I actually prefere rubber to urathane in leafs. I didn't know about the grease thing, good to know.

Nesox, I think my new truck project will be a backyard style build. I want to daily drive it, tow a 20 ft trailer, and still have it corner hard. I have been testing A-arms for a while, and I'm not sure which way o go, so I go back to 'backyard budget' style. I'l give you caster cut numbers soon.

[SCOTI]

Originally Posted by robnolimit

....On the delron type bushings, remember that when one side of a leaf spring goes over a bump, or compresses in a corner, the axle "tips" up on one side. So, either the spring has tp flex (twist) or the bushing does. So, if you use a bushing that won't "twist", then the spring has to twist more than it used to. This makes the spring a bit stiffer. Sperical bearings are the smoothest and have the least bind, but the ride is harsh. I actually prefere rubber to urathane in leafs.

So.... fresh rubber bushings, 'prepped' leafs, & liners for the smoothest leaf operation w/o bind.

I look forward to the 'backyard' approach on the new project Rob.

[spike38]

Originally Posted by robnolimit

I think my new truck project will be a backyard style build. I want to daily drive it, tow a 20 ft trailer, and still have it corner hard. I have been testing A-arms for a while, and I'm not sure which way o go, so I go back to 'backyard budget' style. I'l give you caster cut numbers soon.

Rob

I lowered the truck 3" F / 4" R drop. (CPP springs and shocks)
So to regain most of the lost trailing arm pitch,
I flipped the brackets over. This reclaimed 3 1/4" of the 4" lost.

I removed the 12 hulk rivets, And replaced them with 16
bolts, Flat washers, Lock washer, And connicle nuts.(pics attached)

I also ordered a 24" adjustable track bar, And considering CPP's HD swaybay
kit ( 1 1/4" front, 1 1/8" back sway bars)

Now I'm not building a racer, It will be my DD. It's a 68 stepside sbc,
HD 350 turbo, PB and PS. Converted the front to a 72 disc brake system,
I will convert the back to SS Impala discs.(as soon as the axle arrive)
And moving the tank to the rear frame.

Are there any other mods you would recommend for basic handling.

Spike

[robnolimit]

Scotti, that's the way I'd do it. Any side flex you get from the rubber bushing is less than you get from the tire sidewall. So, unless you'r in stuck in some 'stock' class, that forces all out racing with factory style suspension, you won't notice the flex, except in the improved ride.

Spike. Thats looks great. I prefere a 30" panhard rod, but use the one you got. If you feel like spending a few bucks, look at some A-arms that center the wheel and give you more caster. And don't forget GOOD shocks.

[spike38]

Originally Posted by robnolimit

Spike. Thats looks great. I prefere a 30" panhard rod, but use the one you got. If you feel like spending a few bucks, look at some A-arms that center the wheel and give you more caster. And don't forget GOOD shocks.

Rob

Thanks, That will be on the list.

Spike

[skoffice]

Thanks for the reply Rob! I only have 3" drop springs in mine, hopefully I won't have any problems, but my buddy has 2" drop springs with a coil cut out, I think he has more to worry about than I do.

[BossHogg69]

I'd like to go back and touch upon rear sway bar mounting options with a trailng arm suspension. Some kits mount the bar across the trailing arms with the endlinks mounting on the frame rails (a la CPP), some mount to the rearend itself and the endlinks tie onto the frame, and there is the option of mounting the bar and endlinks onto the trailing arms, tying them together - like a 64-72 Chevelle rear bar. And then you have the blade type bars that mount above (usually) the rearend and the endlinks coming down attaching to the rearend.

It seems to me like mounting the bar to the rearend with the endlinks attaching to the frame, or the blade type that attaches the bar to the frame and endlinks to the rearend would work best at preventing sway in turns, but I have no evidence to back this up. I have the 1.25" bar from CPP on the front of my truck (with CPP tubular upper/lower arms) and a 15/16" rear bar from a mid 80's IROC-Z that I was planning on mounting to the bottom of my rearend with the sway bar arms pointing toward the rear of the truck with the endlinks attaching to the outside of the rear frame rails. I don't have much invested in the IROC-Z bar since it was a junkyard find, so I can change if need be, I just want to use whatever will work best.

[robnolimit]

When it comes to rear sway bar mounting, ther are a bunch of choices. So, lets take a look.
1. Chevelle style, the sway bar mounts in two locations on each trailing arm. This is the least effective set-up. Unlike a Chevelle, the trailing arms are mounted solid to the axle. The combination of the axle and trailing arms is supposed to act like a big triangle and pivit/rotate around the front bushings. The designers (copiers) of this style bar obviousle failed basic geometry.
2. Bar across the bottom of the arms with links to the chassis. (as you listed from CPP) These are OK, we use them from time to time. Install is quick. Efficiency is lost the farther forward (away from the axle) they are mounted, BUT, the farther back you mount them, the more ground clearance you loose.
3. Bars mounted to the axle with links to the frame. The direct link from axle movement to frame (no suppoesed to move) is the most effective set-up. This style, like Hotchkis and Helwig, is a step up. (also like the T.A. bar) Some have the arms forward, and some go back. The back of the frame, behind the axle, usually will flex easier than the front, reducing the efficiency of the bar. Also ALL bar set-ups mentioned so far ADD to unsprung wieght. (bad)
4. Chassis mouned bars with links to the axle. This keep the axle to frame relationship, but looses the unsprung wieght. Definately the hot set-up. Mostly done with a splined torsion bar, and arms. Of coarse if front of the axle is prefered, but spring/bag clearance is tight. Cost and install difficulty are drawbacks here.
For a well built, fun driver would choose type #3, yes, #2 works and will be an improvement, and for those going for the gusto, #4. Notice the lack of #1? I knew you'd catch oc.
NEWS -- I got a look at my new project 72 last night. Not too shabby, but it does have a spiffy 80's sunroof. Oh well, easy fix. I put up picks, but it's raining today.