Poor mans suspension upgrade info.

[Charlief1]

Well I asked once before and didn't get a lot of response but I figured I'd go ahead and post it anyway. This is most likely the only place it will be posted so if anyone want's a copy PM me or just copy it off here.
 
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For the upper control arm you can get the same basic one that Brian sells at G body, from speedway motors. You need 2 of these. The stock control arm is a little under 8.5" from the center of the shaft to the center of the ball joint so you either need to use a longer upper ball joint with stock lower which will give you a 1/2" taller set up and correct some of the camber curve issues that the G body has, or you can use a stock upper and a longer lower ball joint, or longer both top and bottom .

That last statement may sound a little confusing but you can do a lot of different combos with ball joints depending on how you want the car to sit. With the taller upper and stock lower it will sit at roughly stock height. With the taller ball joint in the lower it will sit either 1/2" lower or 1" lower depending on which ball joint you use. A longer ball joint changes the relation of the steering knuckle axis point and changes the way the tires move in relation to going around a curve. The taller spindle height will keep the tire on the outside of the curve from knuckling under (going positive camber) and help on the inside tire from going the other direction. It will keep the tire flatter on the ground in a corner. Prefered is no more than 1" difference in height from stock or it can really change things more than you want.

Upper tubular control arm part number  910-34394 R
1/2" longer upper ball joint part number 721101041. QA-1.
1/2" longer lower ball joint part number  721101091.  QA-1.
1" longer lower ball joint part number    0011277100. Howe.

The G body chasis has bump steer built into it from the factory which means that as the tires hit something in the road and the tires move up and down the toe of the wheels change. This doesn't help handling and it also can create some tire wear issues if the tires are wider than stock. An easy way to correct this is a bump steer kit. What this does is replace the outer tie rod with an adjustable set up. You can get these from several different sources but I've found them for less than Hotchkiss and others have offer them. If you want to understand how this works do a search on youtube for bumpsteer and there are several vids that show the corrections and how they relate to this kit. Once again you can get these from speedway motors. The kit tie rods has both inner, outer, and a sleeve that uses lock nuts instead of clamps on the tie rods. You will need 2 of each.

Bump steer correction tie rod kit part number 910-32800, 18.5" long
Stud kit for bump stop correction kit part number 916-36055GM
Seals for outer tie rods available from speedway 910-01504

As far as a tubular lower, unless you are planing to do a lot of road racing it's not needed, but if you go this way  you'll be happier with heim joint ends instead of poly bushings. If you want to save a little money and make it handle better then you can replace the lower control arm bushings with a greasable steel and teflon bushing. This will give you the advantages of a bushing that won't flex but move up and down much easier. Not a lot of bling factor but you don't have to put out a chunk of cash for something that's not needed. You will need 2 of each bushing for the lower arms since the front and rear bushing aren't the same. You can also get brand new arms without bushings or ball joints in them from speedway if you want something a little better looking.

Lower control arm buishings part numbers:  Front-106-20069LW, rear-106-20076LW

If you plan on changing the rear bushings or arms you'll be much happier with a heim joint type rather than a stock type bushing. The rears have a design that binds them up since the rear sway bar is attached to the lower control arms. To fix this you can get a bushing housing that has a heim type joint in it so the control arms actually move rather than being held in the chasis by the center of the bushing.  I suggest that you box the control arms before you replace the bushings. You can also change the IC of the car with an offset bushing in the axle. These bushings are offset 1/8" which will bring the IC down and rear ward which will give you better traction on the rear. These need to be installed in the car so that you get the position of the right because they're offset.

Replacement rear heim bushing part number 916-34048
Offset axle bushing part number 916-3447

As far as springs go I don't like progresive ones. The reason is because you can't really adjust the chasis for a spring that starts at one rate and then increases in rate as it's compressed. I also don't like the Ebach springs. They're a little to heavy for a V6 car. I do have some numbers that are moog parts that are close to the same rates of the DSE that Scott W (GNS Performance) is using on his car. (575 lbs/in Front and 125 lbs/in rear) For the front of the car a rate of 530 lbs per inch or 598 lbs per inch. The lighter spring will give you a smoother ride but the heavier ones will help the car go around the corners a little better. On the rears I don't increase the rate a whole lot because it's the front that has the most. The rates I chose are either 141 and 133 lbs per inch or 167 lbs per inch. The springs may not look like a stock spring but they will fit in the upper spring pocket the right way. I'll list them as pairs somewhat matched so it doesn't confuse you any. The part numbers are MOOG so you will get a quality spring. These springs will lower the car at least 1" overall from original stock height.

Lighter spring combo part numbers  5658 Front and 6377 or CC617 Rear
or
heavier spring combo part numbers 5660 Front and 5413 Rear.

The other option for the front spring is the 5608 (1" lower at 424 lbs/in) and will stiffen up the fronts some without giving a really harsh ride. The stock spring has a rate of 355 lbs/in and this will give you some options as to what you want to do with the car.

[daveismissing]

This is good stuff. Thanks Charlie.
Would a taller ball joint in stock arms improve geometry?

[Charlief1]

Just going with a taller ball joint in the top or the bottom will help with the camber curve on the car. If you do a little research on the dirt car tech as well as hard track they've been doing it for qite a while. Granted that most of those guys are setting up to run only one way but it helps with the cornering effects if you apply it to both sides. The best option for the steer is a total difference of 1" taller. You can do it with .5" top and bottom or you can do just 1" on the bottom. That's up to you to decide.
 
If you look at the list you'll also see the bump steer correction kit is listed. One of the other issues these cars have is bump steer in the corners or just going down the road. You can get one of these kits from other places by you will pay roughly $100 more for the same parts but they will look prettier.   If you do a little searching on bump steer on youtube you can get a better understanding of how to correct this problem as well as what kind of issues it can cause.

[Top Speed]

Good info.  Nice write up.

[1KWIKSIX]

I recently installed GBody Parts upper tubular control arms (with the greasable spherical steel bushings), also installed 1/2" taller upper ball joints & at the same time installed some UMI lower tubular control arms with Delrin bushings.


All I can say is WOW.  What a difference. Car handles alot better. Seems much tighter & responsive steering.
The instructions from UMI on the lower A-Arms says that their A-Arms feature alignment settings that cannot be achieved using the factory A-Arms.
My car was set up using their  recommended settings for "Street Performance"
-1/2 degree Camber & +5 degrees Caster -Driver Side / +5.5 degrees Caster - Passenger Side


Not sure how these number compare to the factory recommended settings ?


Haven't installed the bump steer kit yet though.

[Charlief1]

The factory parts can do a lot more camber and caster than after market manufactures are willing to admit. The factory settings for caster is supposed to be at 2.5 degrees with a +.5 degrees of camber. These are not performance specs by any means but are for the average grocery getter car. A good alignment tech will know the better specs from seeing a bunch of cars over the years and seeing how the tires wear.


You should've done the bump steer kit before  you did the alignment because once you do it and set it right then you'll need another alignment.

[TURBOPOWERED68]

Do you have a similar write up for A bodies?

[Charlief1]

I could probably do something for you if you want David, but I don't have one written up for them.

[Steve Wood]

additional caster sure helps the stability at speed.....

This is an old trick that we have done for years

One can also install the Moog problem solver bushings in the uppers, but, reverse one from the normal way of install and increase the caster if the stock range of adjustment is not enough

[TURBOPOWERED68]

Offset axle bushing part number 916-3447

this number is NFG at speedway

[Charlief1]

Sorry about that David, I fixed the number. It's 916-34047 that's the offset bushing.

[TURBOPOWERED68]

I could probably do something for you if you want David, but I don't have one written up for them.

please do.
ill start a new thread for my car.
 

[Charlief1]

Send me a PM with what's in the car now if you know or at least what engine and tranny came in it before you put everything together. Have you scaled the car yet to see where the weight sits yet?

[TURBOPOWERED68]

I already have the Tubular upper control arms and new upper Moog OE ball joints.
If i go with these

1" longer lower ball joint part number 0011277100. Howe.

and leave the rest of the steering components OE, What cons could i be facing?


Yes eventually everything is going to be changed but not yet.
Thanks for your help.
David.

BTW i checked Speedway and summit and none have this part number listed.

[Charlief1]

Do a search for that specific part number anywhere other than speedway. Speedway lists the parts in different ways than other sites David. I believe if you contact Jegs or one of the other speed shops they should be albe to look that number up.



You shouldn't have any problems if you don't use the bump steer correction kit. Everything else stays the same but using a 1" longer lower will drop the front of the car 1" rather than 1/2" in the front.