Traction Recipe - simple version

I HAVE MADE SOME REVISIONS TO PAGE #1 OF THIS THREAD.
I emphisized the need to get the rear lower control arms near level to the body to get the IC into good functional shape.
The simplest way to check this is to measure from the ground to the front and rear of the lower arm and see if you can get the front of the arm within 1"-1.5" higher than the axle end.
If you install traction bars (upper or lower) the original lower arms must still be set low as posible FIRST. If this is not done, your no-hop uppers or Southside style lowers, will likely fall into the catagory of "these do not work".

Doublecheck.......
If your original UPPER (yes-upper) control arms slope upward at all, from the axle foreward, you really have no IC; That is why we need the original LOWER arms near level, especially BEFORE adding any type of relocating traction bars.
Don't belive it??? READ EVERY WORD BELOW.

HERE IS THE ABSOLUTE PROOF: Thanks goes to d7cook for these attatchments: see posts 14 and 15.
1. Stock.pdf (25.7 KB, 39 views) ......2.25" up at the front........Look at the STOCK crappy IC (none-no IC)!
2. Lowered1.pdf (25.4 KB, 24 views) ...1.25" up at the front........This is good, especially with a loose front end that lifts.
3. level.pdf (22.3 KB, 24 views) ......0.00 LEVEL ARMS............This is where the rally/handling action is. Some really fast drag dars go level also.
Pay special attention at both the arm angles, upper and lower, near the bottom of the attatchment page.
(No traction bars here, just your factory stuff or equivalent shown here)

 

Hey guys........Look what "TUNA" did............and I quote....

"Previous set up was 90/10s, south side bars, air bag with 11 lbs. averaged 1.60 60 ft.
I pulled a 1.499 60' at Englishtown... with HR rear suspension & ANTI-ROLL BAR."

Tuna

So...
HR does it again, wow.

 

Another simple example: Chevelle

10.80 at 122 and 1.48 60ft... launches hard with no spin,

..... stock front suspension with old NAPA shocks on all 4 corners, and factory front sway bar .......Rear No Hop bars and adj. upper arms, right side air bag,
..... and thats it.



Note: Cars in the low 10's may abandon the upper no-hops or lower lift bars because they become too harsh and hit the tires too hard.
Moser and Strange rear housings have raised upper mounts about half the height of the typical no-hops. These 1" to 1 1/2" upper relocations are suitable for cars from 12 sec to 9 sec or even faster.




.

 

Great Thread, heres mine and it dropped my 60ft times from 1:65, 175 range to 1:47, 1:55 as always depending on the atmospheric conditions. Works whether I use drag radial or slicks.

I have additional features to stiffen the frame and lood the trailing arms together as others have done also.

The air bag has no purpose now.

I am using Strange single adjustment shock which are needed to adjust to track conditions I had had to go from setting 3 to 10 to stop tire chatter at times.

Slugger

 

Slugger:
Looks like you have a Strange or Moser type rear end. Your upper arms are likely raised by 1 or 1 1/2" which improves your IC.
Your anti sway bar looks good too.
Like you said "the air bag has no purpose now" which is common with relocated arms (uppers or lowers).
I'm guessing your 60ft times will = 10.60-10.80 ET 1/4 mi, 6.70-6.90's 1/8mi.
Can't tell if your lowers are stock located or dropped, picture is too small.
Good clean work underneath.

 

The rearend was installed with adapter brackets I designed, jigged and welded on the lincoln Versailles housing. The lowers arms are factory, boxed with 1/8" flat stock with poly bushings. I built the Upper adjustibles arms last year after I calculated the Instant Center and Anti-squat and determined that I needed to make adjustments to the Instant Center of the car to a vertical line just forward of the center of the doors and on a 14" above ground level on the horizontal line. This location gave me Anti-squat of about 106% which is as close as I could get it when I ran out of adjustment on the upper brackts.

Thats when the front tires came off the ground!! I built the Anti_sway bar to level the launch a bit and eliminate the airbag and went to the stock springs.

Some one else thought the 60 ft times should be in the 10:80 et area which I feel is a real compliment because my ET's are almost exactly 10:00 sec more than my 60ft times on each pass and that is 11:50s @ 115.85MPH.

Now if I can just find the HP to get in the 10's.

Slugger

 

Gary, somewhere I have heard or read that in the low 11's and faster you want to take the no-hop bars back off? o No:

BTW great thread:TU:

Thank you for sharing:beer

 

Dave,
I'll try to make this as simple as I can.

First I need to mention that some guys get incredable 60ft times with no traction bars at all. They generally have one or more of the following:
1. Loose front end that rises fast at launch.
2. No binding at the rear control arms; due to flexable poly bushings, delrin bushings, johnny joints, heim joints. or simply leaving the bolts loose enough in all 4 control arms to allow free movement at the stock mounts. (HR has arms with flexable poly bushings)
3. Rear Anti-roll bar, such as HR bar, that hooks to the axle and frame only.
4. Lower control arms with the front of the arm no more that 1.75" higher than the rear. Preferable lower, or even level.

No-hops are good but:
* If they are too tall (3"+), like Lakewood and Edelbrock upper no-hops, they are harsh and often lose traction after the initial hit at the line. These usually get removed and get bad publicity.
* TA no-hops are shorter (about 2.875" above stock) and often work well into the 10's. With a poor suspension, they may not be able to perform properly. Soft springs and low stance should help.
* Dick Miller type bars have holes for heim joints, that allow different heights for the arms. The lowest hole setting (about 2") is similar in height to the aftermarket housings and is often the choice for faster cars that use GM 10 or 12 bolt rear ends. (expensive)
* Aftermarket rear ends such as Moser and Strange, have elevated upper control arm holes rising about 1" to 1.5" above stock, and will be desirable for good IC location on virtually all fast doorslammers. (very expensive) THIS IS GOOD FOR 11,10,9 SECONDS AND FASTER.

Other factors are:
Front end lift, ride height, shocks, IC location.
* For your 11 second car, get that front end to rise at the moment of launch.
* The angle of the lower control arms is very important. The FRONT of the lower control arms should NEVER be more than 2" higher than the REAR from the ground up. Most racers say level is best, but some get good results up to 1.75" if the front end is loose and rises fast.
* Moog 5230 front springs, and Moog 5401 rear springs should have your lower control arm about 1.25" higher in front, get good front end lift, and have a good IC location (near 100 percent anti-squat) for the TA no-hops.
* Shocks...try cheap gas shocks first. Go to adjustables only if needed.
* Set pinion angle and front end alighment after changing springs and adding traction bars. Loosen and retighten ALL attatchment point bolts on front and rear control arms to allow bushings to reset under load. (not jacked up)
Hope this helps.

 

Slugger,
You have done some amazing work on your suspension. Your traction efficiency is waaaay out there.
http://www.v8buick.com/showthread.php?t=212126
I wonder how many can match your efficiency rating, per this chart.

I would like to know your IC setting (If you know it). ....EDIT.... How many inches forward of the axle is the IC?

Thanks for sharing that info. Gary B.

 

So, you're saying leaving the anti-roll bar in actually helps straight line traction? That's interesting. Usually that's the first thing to go if you run the strip more than the street.

 

The anti-roll bar in question is a rear bar, not a front as I believe you are talking about. Yes, the front bars help handling on the street but hinder on the strip. Most street/strip guys either remove the front bar to go to the track or loosen it up to allow it to travel more freely.

 

Are you referring to the front sway bar?

There is a difference between a stock sway bar and an aftermarket anti-roll bar for the rear.

 

Thanks for clearing that up. For some reason I thought he was referring to the front.

-Matt

 

Some guys are claiming that adding an HR anti-roll bar on the REAR helped the handling when the FRONT bar was removed.
Sounds good to me.

 

I believe Gary is refering to the rear sway bar, not the front. Lose the front, keep the rear. I use an ADCO 1" rear, worked better than the factory 3/4" one.

 

please make this a sticky, great thread.

 

Attention:
Made some revisions for clarity and added a few tidbits of new info on POST # ONE of this thread.

Always seeking more information about these old Buicks; can't get enough.

 

Gary what are your thoughts on using drop spindles and the 5230 springs up front. I am planning on using 26" tires up front and 28's in the rear with the 5401 in the rears. I have the complete suspension wiped out of my car right now and I am just looking at options. I allready have stock height spindles and a an H&R rear bar with comp eng adj shocks, just the cheap ones, along with wolfe sphereical bushings for the upper housing and aftermarket non adj uppr and lower rear control arms.

How important is getting the front down as in the rear? Would this help get the rear lower bar level?

thanks :beers2:

 

David,
Lowering the body will result in:
* pointing the pinion downward
* moving the back tires reaward
* altering the front wheel alignment comletely
After lowering my 1967 GS, the rear tires (28" & 10"tread) rubbed the back of the wheel wells. This required adjustable lower control arms to pull the axle foreward. Tires 26" dia may work with stock length arms. The pinion angle correction will require adjustable upper arms. Get arms with at least one end that swivels (rod ends or super poly flex joints, etc.) for less bind.
My car with the same diameter tires you have and same springs, is near level, and a full tank of gas will likely level it.
As for getting the frontend up, loose is more important than stance. Use Global West Del-a-lum bushings on an offset upper-inner shaft. Your front controll arms will be on bearings and launch skyward under throttle. The offset shafts will improve alignment.

The dropped spindles will help lower the body height but you need to look into this thoroughly to decide if this will be more good than bad. Never tried this but have heard pros and cons. Search this site and try chevelles.com, and others for more info.
Dropped spindles and 26" MT 275/50-15 ET Street Radials would make a bad ass low rider for sure.