Suspension Anxiety...

[68-GTO]

I just got my ’68 GTO, now my imagination takes over. I plan on doing everything to the suspension to be able to autocross/track the car. I’m not ready for the coil conversions or the fancy frame mods, so I plan on doing a suspension overhaul with one or more of these brands, Global West, Hotchkis, and SC&C.

I’ve been reading about these brands to see what they have to offer, but so far I’m not sure which one is the right one.

One difference I notice between GW and Hotchkis, is that GW uses tubular U/L control arms and Hotchkis uses boxed style arms, are tubular arms better than boxed arms, or can you really tell the difference?

Another difference I noticed between them is their bushings. GW has a Del-a-lum bushing that really sounds like a performance plus for street/handling cars. Hotchkis uses greasable polyurethane bushings, just like a lot of other suspension brands. GW says even with the greasable bushings, the polyurethane creates rear suspension bind for street and handling cars. Is this true, does anyone experience any binding problems from poly bushings?

Besides these differences they both offer pretty comparable parts, Hotchkis has thicker sway bars for the front and also has lower sport springs.

One other thing both companies have are tubular A-arms, Hotchkis is still designing their lower A-arms and should be out this coming January. I first heard of GW for there A-arms and there are a number of people running them. Are both brands A-arms pretty evenly ranked in performance? Just the other day I was reading the (’72 Chevelle GW susp) thread and saw that SC&C makes A-arms that are a lot less expensive and out perform the GW A-arms, I saw what Derek69SS posted, OK, assuming you want a mild street setup:

My suggestion for the front: Stage II package from SC&C http://www.scandc.com/suspensions.htm - This will do more for you than the GW setup by a long-shot. You have the option to keep your stock brakes and 15" wheels, your geometry is improved, It's cheaper, and you reduce bump-steer and keep your turning radius. It will drop your car about 3/4" in front. Something like a Hotchkis spring and a 1-1/8" sway bar will work well if you want to keep the smooth ride, and don't intend to autocross the car.

In the rear, keep your stock upper arms and put new rubber bushings in them. Lowers, you could use the factory F-41 style boxed arms and 7/8" F-41 sway-bar. Again, just use rubber bushings. Don't use any poly-urethane/poly-graphite or delrin bushings in the rear. The binding will make the car ride like crap, and handle mediocre at best.

now if you want to autocross it... :unibrow: I've got some different suggestions :thumbsup:

The SC&C A-arms sound like a better alternative than the GW and Hotchkis.

So if someone could please assist me and steer me in the right direction for my suspensions sake, and lay my suspension anxiety to rest :willy: , every comment is well appreciated. I'd also like to hear your autocrossing suggestions Derek69SS.

Thanks, Brian.

[sinned]

Another difference I noticed between them is their bushings. GW has a Del-a-lum bushing that really sounds like a performance plus for street/handling cars. Hotchkis uses greasable polyurethane bushings, just like a lot of other suspension brands. GW says even with the greasable bushings, the polyurethane creates rear suspension bind for street and handling cars. Is this true, does anyone experience any binding problems from poly bushings? OMG, you need poly bushing 101 for the rear arms for sure. BTW, while doing your reading, anything negative said for running poly bushings in the rear arms goes triple for running Del-a-Lum or Teflon bushings. Check the following links (I'd copy/paste it for you but it's about 30 pages worth or so).
post #1 (http://www.chevelles.com/forums/showthread.php?t=99326&highlight=poly+bushings)
post #2 (http://www.chevelles.com/forums/showthread.php?t=31248&highlight=poly)
post #3 (http://www.chevelles.com/forums/showthread.php?t=85246&highlight=poly+bushings)
post #4 (http://www.chevelles.com/forums/showthread.php?t=84208&highlight=poly+bushings)
post #5 (http://www.chevelles.com/forums/showthread.php?t=31248&highlight=poly+bushings)
post #6/my personal favorite (http://www.chevelles.com/forums/showthread.php?t=30655&highlight=poly+bushings)

[Derek69SS]

Front: Poly bushings are good, delrin bushings are better

Tubular lower A-arms - they all keep the exact same geometry, and most weigh about the same as stock arms, so you're not shedding much, if any unsprung weight. The only advantage tubular arms will get you is added strength, and they look cool. You can box your lowers for far less to make up for any strength concerns.

Tubular upper A-arms - There are a lot of options for these, from the $49 circle-track arms that are built very light to the beefy $569 GW arms with delrin bushings. They all do 1 thing - they are shorter to allow for a taller spindle. I prefer the SPC adjustable arms from SC&C for $269. I plan to use them to get the car aligned, then lock in the lengths and use shims to make an easy to reproduce "track" alignment setting.

Spindles - read this http://www.chevelles.com/forums/showthread.php?t=107745 I think I covered all the popular spindle swaps. The best options available out there are the stock spindle with tall ball-joints from SC&C, the tall drop spindle from Fatman, and the AFX spindle from ATS... I think the tall ball joints are the only ones currently available though.

Rear: Poly is bad, Delrin is WORSE. Rubber is good, and spherical rod-ends are better.

If you want a cushy ride, stick with rubber uppers in your stock upper arms

If you're more concerned about handling, go with something like Wolfe Racecraft (http://www.wolferacecraft.com/SearchResult.aspx?CategoryID=28) arms with spherical ends, and their spherical bearing for the housing.

[68-GTO]

thanks Dennis68 for those links, lots of info. that i needed.

also thanks Derek69SS.


what are both of you running for bushings in your rear arms?

[68-GTO]

Derek, i noticed you posted about getting the Wolf Racing double adj. arms in all 4 spots with all solid spherical bearings...

i was wondering did you finally get that setup, if so, how do you like it?

thanks for that link, i'm considering that same set up.

[sinned]

Wolfe race Craft housing pivots, Edlebrock upper links (bushed rod ends), my own design lowers (sphericals all 4 locations).

http://www.onrails.us/images/rear.jpg

[Derek69SS]

Derek, i noticed you posted about getting the Wolf Racing double adj. arms in all 4 spots with all solid spherical bearings...

i was wondering did you finally get that setup, if so, how do you like it?
No, I do not have them yet... my current setup is a perfect example of what not to do - poly upper bushings, and teflon lower bushings. The ride is horrible :rolleyes: I can't speak for the ride of the solid bearings, but it can't be any worse than what I've got now. :mad: **note to self - do more research before blindly buying products based on what the ads claim**

Denny, you mention the bushed rod ends (Johnny Joints), how well do they wear compared to a solid rod end? Better, worse, same? Does anyone make a lower arm with those on both ends? That seems like a good alternative to having a fully solid setup, as long as they hold up to a lot of use.

[sinned]

The bushed ends will last virtually forever, Teflon products have VERY long wear lives.

Look into Currie arms, I'm not sure if they offer lowers or not. You could be real brave and build your own by purchasing some Jonny Joints and threaded tubing, I think Vince is working on building some links.

Vince???

[68-GTO]

Dennis i can tell why post 6 is your favorite. You posted alot of information that was well needed. Everyone could learn from that thread. :thumbsup:

Are the UMI UCA's the ones you would recommend over any other double adj. UCA's?

What would you recommend for the axel end of the UCA, what are some other alternatives, i now know poly is the devil, and you posted this on the chevelle forum...

Note:something I forgot to mention early on in the thread is that not only does the poly induce bind as a result of it's inability to allow "twist" in the arms but as the axle rolls the arms NEED to change length. Obviously a solid link cannot change length so the bushings give allows for some movement, this is why the bearings in all positions do not work.

I would guess that with the johnny joints in the front of the edle brook (inside joke) and rubber bushings at the axle there at least be some compromise.

So is rubber on the axel end the only other option?

Also, for the LCA's, i was looking at the Wolfe Race Craft LCA's, they look similar to yours in the picture. Are spherical rods (jonny joints?) on all corners the best thing to do when it comes to LCA's?

Thanks for the info/help to steer me in the right direction, i would have felt like a douche bag for not doing such thourogh reseach and ending up with poly bushings.

-Brian

[68-GTO]

Woops, forgot to ask for a comparison between Wolfe Race Craft LCA's and UMI's LCA's...

i was first interested in the WRC's, probably just because they were the first spherical LCA's i saw, you know how that goes. But now it depends on which ones are better.

And if there are more companies with spherical rod LCA's let me know, also which of them you'd recommend.

thanks, Brian.

[sinned]

Yeah Brian, technically the axle bushings should be rubber but I ran the WRC to see how it would affect the overall handling and was suprised to see theywork quite well. Keep in mind I run 175 lbs springs and have a rear suspension travel limted to ~3". With more travel the inability of the links to "grow" may or may not present a problem, also less spring rate may have revealed a problem as well-I don't know for sure.

The only upper links I recommend using are the Edlebrock arms or Currie Enterprises (unless somebody else has finished devlpment of some form of copycat arm).

There are a ton of guys building spherical LCA's, they are real easy to make-2 left rod ends, 2 right rod ends, 4 jam nuts (2 left/2 right), and 2 peices of threaded tubing. ~110.00 for all the materials. Check out Sppedway Motors or Capital Motorsports.

[Derek69SS]

i would have felt like a douche bag for not doing such thourogh reseach and ending up with poly bushings.You mean like I do right now :rolleyes:

[mrgto]

www.bmrfabrication.com offers rear susupension parts also. I have used them with great sucess in my F-body and I have the rear for my A-body.

[68-GTO]

Damn i didnt know the LCA's would be so easy to make, now my only questions are, how do i pick out the right pieces to fit my car, i noticed they make the threaded sleeves in various lengths, and there are a number of different rod ends. Also the thread size, 1/2", 5/8", and 3/4", which size do you recommend?

[68-GTO]

Could you show me a link to the Currie Enterprise arms that fit the GM A-bodys, the only ones i found are for jeep?

[sinned]

Go big---3/4". I beleive I used 20" links, it's been a while.

Currie (http://www.currieenterprises.com/cestore/categoriesre.aspx?id=1144)

[Vince@Meanstreets]

Look into Currie arms, I'm not sure if they offer lowers or not. You could be real brave and build your own by purchasing some Jonny Joints and threaded tubing, I think Vince is working on building some links.

sorry, i've been busy.
We did finish my friend Ricks 71 Malibu and we went with "Edelbrock" :unibrow: upper adjustables, Wolf sphericals, custom lowers (Adjustable from 19.5"-22") with JJ's and a custom panhard bar.
We were told that the car would not work with joints at all points but it worked fine... we added the PHB 3 weeks later. I would have expected the car to handle like a wet noodle but I believe the link convergence takes care of the slop....any problems with you set up Den?

both lowers cost around $200 to build...the left handed bolts are pricey...if you can find them for less than $20 each go for it. We had ours custom made. We had hoped to get some track time on the car but they popped out another baby so we will see.
to get JJ's at both ends you would have to make em.
vin

[sinned]

Good to hear your links worked out, sounds like there be a few folks in the market for something like that.

Me, no problems at all. 1 track day and 10K miles of very hard street driving...nothing I would have done different.

[Marcus SC&C]

Dennis,what state do you live in? Do you drive the car in the rain and such? I`m wondering if the precipitation and grit left over from winter road cindering etc. in this part of PA. may have anything with accelerating heim wear. Over the years we`ve had less than sterling luck with heims,even the very best teflon lined ones. A couple years and they`re worn sloppy enough to buzz and rattle. I just replaced a set of 1" teflon lined heims in the ladder bars of a customer`s ProStreeter that were only in for 3 seasons (just shows and cruising,no racing). Our G-5 test car`s top of the line QA1 heims were buzzing at 13,000 street miles (that`s daily driving,as in EVERY day). Once they loosened up they went south fast. It may not be an issue on and Elky because you don`t have a large echo chamber (trunk) over the rear suspension? I`m fairly certain the cage in our car make it worse also,transmitting the vibrations through the whole car. It was *very* (as in,give you a headache) annoying. Marcus SC&C

[sinned]

Nor-cal, not the worst weather anywhere but it does rain a few dozen inches annually and yes, I drive everyday rain or shine. I should also note that I work for a heavy equipment contractor and spent A LOT of time in the dirt and mud so that kind of evens the playing feild.

[Vince@Meanstreets]

I can confirm dennis's "dirt" time! :yes: LOL
But I agree, heims after time become noisy and offen fail if left unattended and unserviced. Combined, that can create a dangerous situation.

I love the johnny joints, rubicon flex is nice too. Its sealed and easily serviced. I believe they (you) would most likely survive in event of a failure. vin

[68-GTO]

So how long do rod ends last? A year or two?

But even before they start to rattle, arent rod ends the best rear suspension solution for fixing bind issues? (in A bodys)

So far from this thread i've come up with an idea for my U/L control arm and bushing set up. For my UCA's i'm looking at the Currie Enterprise double adj. with Curries Jonny Joint, i guess i'll be using rubber bushings for the axel end. Then for my LCA's im going to be building a set with rod ends on all corners, built with parts from Speedway Motors. I'm looking at the 3/4" threaded sleeves, but for rod ends im still unclear of what i should look for in their construction, Speedway has a number of rod ends and i have no clue what to look for, they have steel, female, male, precision, and heat treated rod ends. Whats the difference, and how can you tell?

Which rod ends would anyone recommend for a daily driver partially tracked car?
Or should i look somewhere else that has better rod ends, i noticed Marcus SC&C mentioned QA1...

[sinned]

By the best you can afford. QA1's are real nice ends, the Speedway PRO-1 is a very good end as well.

[race-rodz]

has anybody tryed the rod end "seals" that speedway sells? just curious if they would help the life expectancy out a lil bit.

[Marcus SC&C]

I like heims best for race cars. Now that Currie Jonny joints and Rubicon Express ends are available there`s no reason to compromise. They`re not much more expensive and they`re weather sealed,rebuildable and offer some NVH isolation. We`ve tried Seal-Its. They`re better than nothing. They don`t work in some double shear applications due to the thickness of the washers the rubber is vulcanized to. They keep grit out better than water but again they`re better than nothing. I`d still just go with Rubicon or Currie joints for the small difference in price. Marcus

[68-GTO]

Marcus are you saying use jonny joints for the LCA's or somewhere else?

[sinned]

JJ are a better alternative anytime a suspension link is in question, unfortunately they are fairly expensive. The more often you can use them the better off you will be.

[Mean 69]

JJ are a better alternative anytime a suspension link is in question, unfortunately they are fairly expensive. The more often you can use them the better off you will be.

They are really freaking big though! The 2.5" unit is a reasonable size, but the bolt that you attach to the frame is pretty small (9/16" IIRC?), not good enough for us. The next size up is huge.

The QA1 "XM" rod ends are really hard to beat, super strong, and "cheap."
M

[sinned]

I like the Speedway "Pro-1" myself.

[Marcus SC&C]

Yeah,I like the Jonny Joints or Rubicon Express joints in rear suspension arms better than anything else right now. We`re very big on zero compromise components. They work very well and have no downside. Hell they`re not even that expensive,really good heims cost just as much. The 2.5" OD version works just dandy. 1/2" bolts were fine for the factory,9/16" bolts are more than strong enough for any ProTouring car. You`ll snap the thin cast iron mounting ears off the top of the rear end housing long before you snap a 9/16" grade 8 bolt in double shear. Marcus SC&C