MonteCarloSS.com
MonteCarloSS.com

CELEBRATING 20 YEARS!

Previous Thread
Next Thread
Print Thread
Page 12 of 12 1 2 10 11 12
#1073904 - 05/13/22 10:57 PM Re: Front sway bar project [Re: mmc427ss]  
Joined: May 2007
Posts: 5,091
Buick Runner Offline
10+ Year
Buick Runner  Offline
10+ Year
Member

Joined: May 2007
Posts: 5,091
Dharma station 1 the Hydra
Originally Posted by mmc427ss
You would think there would be a bolt in rack and pinion that would be better than the present stock system. Unfortunately there isn't, why, for the same reason the stock system isn't very good, the crossmember would need to be moved back to make room for a rack. There is a way to fix that problem, Schwartz and Roadster Shop fixed it, an entirely new design chassis with no stock parts and a price tag to go along with it.

Got all the static alignment numbers from the car today. Virtually the same left and right. And what i set almost 4 years ago when I did the LCA relocation. That tells me the mods and welds and all that thinking back then has stood the test of time and near 10K miles.
Toe was 1/16' out.
Camber - 1 1/4, Caster +9 3/4
Camber at 20 degrees in -3 1/2
Camber at 20 degrees out +3 1/2
Ackermann at 30 degrees is only +1 degrees to the inside wheel. This is the area I'm looking at to improve.

Got to the point tonight of the left side coil spring is out and new sway bar arm and link hanging on the bar, Tomorrow will pull the right side apart then it's set the car back at ride height and locate the link lower mount to the LCA. Moving the suspension through full travel is easy now, can really see how the link angles are going to move. Should have both the LCAs out, paint removed from mount areas and hoping to have a plan to build up the arms to accept the mounts. Once the LCA are laying on the bench for mount work the rest is easy.
About time, I know.
Bob



Similar thing happened with Ford Panthers. Ford completely redesigned the Panther chassis in 2003 to fit in rack and pinion steering. Retrofitting R&P steering into a older chassis design isn't easy.


SBC powered 1987 Regal with TES headers, ZZ4 intake, ZZ4 PROM chip, mini starter, THM2004R, 2500 stall converter, 2040 cam, CCC system, and 3.73 posi rear.

2008 ex NPS P71 Crown Victoria, cop motor, cop shocks, cop brakes, and Jmod.

Never argue with an idiot.
They will just drag you down to their level and beat you with experience.
#1073907 - 05/14/22 05:16 AM Re: Front sway bar project [Re: mmc427ss]  
Joined: Jan 2000
Posts: 5,581
mmc427ss Offline
20+ Year
mmc427ss  Offline
20+ Year
Member

Joined: Jan 2000
Posts: 5,581
Pottstown, Pa
Both LCAs now out of the car, POR and black top paint coat removed with stripper, wire wheeled at the construction site, the delalum bushing cleaned of grease, ball joint boots removed and it was off to see the TIG guy with one LCA, one sway bar link lower bracket and an attempt at fabricating a pad to weld the mount to. After some discussion the plan is tomorrow evening to tack weld both the L and R mounts in what i think is their final resting place, no pad needed. Then take the LCAs back to reinstall on the car to check link articulation. I do think it will be fine, but need to know for sure before they get welded completely.

My welder says the ball joint will get cooked when he's welding the mounts in, grease will spew out all over his bench. He wants the ball joints removed. Because the mounts are very close to the ball joint they interfere with him getting his nozzle into that space. So joints will be removed. I was going to replace the left anyway. Tonight ordered another ball joint so now two new joints will be going in.

Will be getting the coil spring rate checker down from the mezz. Curiosity say i need to check the front springs I removed from the car. 20 years ago they were a 640 lb/in, i cut a 1/2 coil off 4 years ago. A guesstimate said they should be 675 after the cut. My spring rater checker was made for the rear coil spring project a few years ago, but will fit the front spring also. I will preload the spring with 250 psi and then compress 1". The max psi on my checker is 1000 due to the gauge used, 1000. I could change the gauge to a higher pressure gauge but felt 1000 psi was my comfort level on the rate checker i made.

I think it was Unisteer that made an attempt at a rack for a G. OK for a drag car that only goes in a straight line if i recall.
Bob

#1073909 - 05/14/22 09:08 PM Re: Front sway bar project [Re: mmc427ss]  
Joined: May 2002
Posts: 4,376
MAP Offline
15+ Year
MAP  Offline
15+ Year
Member

Joined: May 2002
Posts: 4,376
Yuma, AZ
The problem with the A/G body is that the front LCAs are very long, and the distance between the inner pivot points very short: far too short, in fact, to fit a conventional R&P steering unit. A work-around is to use an offset tie-rod coupling scheme that, unfortunately, tends to twist the rack when the tie-rods see simple tensile or compressive stresses. This isn't a recipe for rack longevity. For good R&P, there's no question the whole OE front end needs to be replaced (and, I would say, good riddance, like most of the rest of the car's chassis and suspension.)

Last edited by MAP; 05/14/22 09:10 PM.
#1073910 - 05/14/22 11:30 PM Re: Front sway bar project [Re: mmc427ss]  
Joined: Jan 2000
Posts: 5,581
mmc427ss Offline
20+ Year
mmc427ss  Offline
20+ Year
Member

Joined: Jan 2000
Posts: 5,581
Pottstown, Pa
Forgot to mention last night, registered my son and I, AM and PM sessions, June 4 autox in Harrisburg. The math says that is less than 21 days away so the pressure is ON, get this sway bar project DONE.
Ran that lot twice last year, 30 runs total between the two of us. Should be a good test of the new bar verses old bar. Also that could be a day out for my daughter's family, go watch Pop and Uncle J beat up on the grandkids inheritance. My 13 year old may even be old enough to get "ride alongs". Now i need to think about helmets for that crew.
https://www.scca-susq.com/autocross/calendar/

Making a trip to my TIG guy tonight to tack the mounts to the arms. If I were to get out of bed early tomorrow and get all the flowers and the vegetable garden planted the yard weedwacked, grass cut. even try out my new corn broom. Then I may to able to slide to the shop and install the LCAs and check the mount locartion and link angles. Then pull the arms and get them back to the welder after i remove the lower ball joints. Sound like a plan for tomorrow. Good luck won't help, thanks anyways.
Bob

#1073912 - 05/15/22 01:20 AM Re: Front sway bar project [Re: mmc427ss]  
Joined: Feb 2020
Posts: 679
88ssBrent Offline
Member
88ssBrent  Offline
Member

Joined: Feb 2020
Posts: 679
Friendsville
Sounds like you have a busy day tomorrow!

#1073918 - 05/15/22 10:45 PM Re: Front sway bar project [Re: mmc427ss]  
Joined: Apr 2011
Posts: 1,234
Hunter79764 Offline
10+ Year
Hunter79764  Offline
10+ Year
Member

Joined: Apr 2011
Posts: 1,234
Grand Prairie, Tx
I keep hearing from people that aren't retired that you get a bunch of extra time when you do retire. But from everyone I know who has actually done it, they say they don't know how they ever had time to work for 40+ years before "retiring". Your day sounds busier than mine for sure.


Shawn

'85 MC with budget 5.3L swap, TH350 with stock 2.14 rear end
It ain't much off the line, but it's nice on the highway
#1073923 - 05/16/22 04:42 AM Re: Front sway bar project [Re: mmc427ss]  
Joined: Jan 2000
Posts: 5,581
mmc427ss Offline
20+ Year
mmc427ss  Offline
20+ Year
Member

Joined: Jan 2000
Posts: 5,581
Pottstown, Pa
Six years and trying to figure out why time goes faster now. For 25 years I have kept a note paper in my left rear pocket, it's were the things i need to do end up, noted on an 8 1/2 x11 folded into 16 x 2 gives me 32 entries, good for a couple weeks. Oh, it's my Prevagen.

Actually got.the list of yard stuff done, 50 plants planted, a trim and a cut, even some weed control, all caught up for a week. To get all that done a trip to the shop early this morning was done first. The final fit, some grinding of the link mount, now parallel in two plane to LCA,, had them clamped and ready for tacking.

The final link length now is determined by having the sway bar level at ride height, the lower link mount set in the LCA as low as possible. The goal is 4" center to center of the 1/2" rod ends. Longer link is good, too short of a link not good.I think the link on the old 36mm bar was 4 1/4".

Tonight after my gas grille ran out of propane while cooking a thick rib eye I was able to hop the fence and use my neighbors gas grill to finish. Oops, guess i used a lot of propane when the gas grille was used for the arm welding. I'd like to say that was the highlight of the day but after i finished the dishes I ran over to my TIG guy at 8 pm and we tacked both mounts to the arms. So tomorrow they get installed and for the first time actually see the sway bar and LCA interact as the spindle is moved 1 1/2" compression to near 4" full droop. A full droop stop is handled very nicely by the Global West UCAs, a steel tube in the center of that GW arm contacts the frame. S10 ZQ8 bumpstops on the LCA limit max compression to about 1 3/4". So range of motion is clearly defined.

I've resigned myself to the fact that I will need to be happy with the location of the mounts. I know the top rod end should move closer to the frame to improve angle, can't happen, maxed at 1/8" working clearance.
The bottom rod end needs to be moved closer to the ball joint to reduce angle, can't happen, a tool to install a balljoint needs some of that real estate and a ball joint boot need to also live there.

Maybe have the LCA back for final mount welding on Mon evening, Wouldn't that be special?
Bob

#1073929 - 05/17/22 07:19 AM Re: Front sway bar project [Re: mmc427ss]  
Joined: Jan 2000
Posts: 5,581
mmc427ss Offline
20+ Year
mmc427ss  Offline
20+ Year
Member

Joined: Jan 2000
Posts: 5,581
Pottstown, Pa
I was hoping to install the LCAs this morning and throw a stamp of approval on the mount location so the arms can get that final welding done. NOT!

With the LCA arms installed and links now firmly attached to the LCA real time articulation of this sway bar to LCA relationship can be scrutinized to see where, if, how, these pieces are going to play with each other. With some measurement and marks on the frame here and there getting the LCA set to ride height is done and the LCA blocked at that height. It's just a heavy B spindle and both the upper and lower arms are delrins so moving spindle up and down 6"' is pretty easy.one hand operation.
That was the first time since starting this project where all three pieces of a three piece bar were glued to a LCA and moving as one. Huge step!

After both arms were installed and run up and down they both were pulled from the car, the tacked on mounts removed and the mess cleaned up. At full droop the OD of the bottom rod end in the link, it's a 1/2" female, would hit the ball joint boss on the spindle. That clearance there is decreases rapidly as the last 1" of droop is added. That rod end binding on the spindle will actually prevent the suspension to drop to full droop and the droop stop on the UCA is not touching.
So back to the welder after diner tonight and tack both mounts inward a little, less than 1/8".

Back to the shop tonight to reinstall and check arms. Well, the right side is better now, .050" clearance minimum now. The left side, the link mount is again removed, the mess cleaned up, tomorrow will clamp that arm to his welding bench, setup and clamp that damn mount and tack it, check it and then nail it. Third time is a charm, no choice here.

Called my friend with to many tools this morning. will borrow his ball joint tool tomorrow and remove the joints before final welding, hopefully done tomorrow night.

With the Intercomp digital angle gauge, love it, was able to get angles off the links in two planes at full compression, ride height, full droop, ran two sets of numbers on both L and R sides to get a better idea on that process.

Couple initial observation: I can relate the link angles in the same context as caster/camber. When the welding is all done and the LCA and full sway bar are installed again will double check number to verify.

Camber of links on both sides is good, not great, good . Left side had -2 degrees camber right side was -3 at ride height height, about the same at full droop but at full compression 7 degrees.
The reallocation of the mount for the third time should correct the differences in angle at ride height between L to R.

Very happy with link camber at 3 degrees in the working range of the suspension with is + or - 1 1/2" from ride height. The 4 degree "twist" on the end of the sway bar arm was put there to accommodate that 3 degrees of camber of the link. That top rod end moves very little.

Caster I knew was the big compromise. The location on LCA for the mounts is limited, to like only one place if you want to do a big 1/2" rod end and make the link as long as possible. Only one place to do that is in the valley next to the ball joint. So it moves the bottom link pivot point rearward, this becomes - caster. In the 5 to 10 degree range through most of travel but very high at full compression. This because both arcs, the LCA rotating and the sway bar arm's arc conflict at full compression

Will revisit all those measurements again after mounts are welded.
A check of the lower rod ends at max suspension travel up and down show they are near maxed out in their 18 degrees of travel. Not in bind but very close.

So final welding, new ball joints, some paint and may be able to say the sway bar is done by the weekend. Didn't think i'd ever get to say that. Once the front suspension is back together in autox trim the link length and adjustments will be done at ride height.

Pulled my coil spring rater down from the mezz today to measure the 20 year old front spring from Global West. The rater was made when the rear coils project need a way to accurately check how these new fangled variable rate rear spring measure up. I constructed it with the intent of strength need to do 1000 lbs pressure safely.
Because a stockish front coil spring has a tangential bottom and ground flat top it took a little thinking to get the tangential end to sit nicely on the rater. Tried to get some good numbers using my 1000 psi gauge but figured out to get an accurate rate of my spring need to throw more psi at it. So the 1000 psi gauge came out and the gauge I have to do power steering pressure, 2000 psi, went into the rater. I thought i need to get the spring compressed to 1000 psi, a nice round number but also close to what the corner weight is on the front of the pig. So pumped the jack up to indictated 1000 psi, let it sit awhile and tweaked pressure to maintain 1000. Next is slowly compress spring 1", slowly, yep, safety glasses on, then read the gauge at 1", 1700 psi. I guesstimated 675 when i cut 1/2 turn from them to lower the car a little. So the rater didn't blow up and i ran that test twice and got the same 700. Those springs are going back in.

gettin there.
Bob

#1073932 - 05/17/22 03:08 PM Re: Front sway bar project [Re: mmc427ss]  
Joined: Dec 2007
Posts: 6,600
SSLance Offline
10+ Year
SSLance  Offline
10+ Year
Member

Joined: Dec 2007
Posts: 6,600
Peoria, AZ
Been there done that Bob... I think I shared the pic of the link mounts cut off the car and in a pile of scrap on the floor after my first go around. You just don't really know until it's all held in place and cycled.

You got this though, you are doing it the correct way and the results will pay huge dividends.


Lance
1985 Monte Carlo SS Street Car
#1073934 - 05/18/22 05:05 AM Re: Front sway bar project [Re: mmc427ss]  
Joined: Jan 2000
Posts: 5,581
mmc427ss Offline
20+ Year
mmc427ss  Offline
20+ Year
Member

Joined: Jan 2000
Posts: 5,581
Pottstown, Pa
Got a little more done today on the LCA link mount. Picked up the ball joint press from a friend at 5:30, then straight to my shop and figure out how to use the press, ball joints now out and at 7:00 the LCAs are getting the mounts welded, FINALLY. Back to the shop and prep the arms for paint first , pressed the new ball joints in and masked up the LCA for paint tomorrow.
Before painting will open up the access holes in the bottom of the arms, where the shock attaches. With the double adj Viking shocks their knobs are hard to get two fingers on to turn the knob, I relieved that area for more clearance when the shocks went on initially. Will now remove a little more.

On the shafts of those shocks are green O-rings that are used as indicators to show max shock compression. When the shocks were pulled both O-rings said there was still 1/2" travel left before bottoming out the shock. Cool. Several years and didn't bottom. Viking was good about allowing me to exchange the shocks to get a shorter shock to better fit my setup, thanks Chris.

Found a piece of 3/16" x 1" mild steel in the pile on the bench and will make two taps that will be welded to the frame where the UCA droop stops hit the frame. This car has near 4" of droop from ride height, probably typical. Will be able to check how much a .187" change in the droop travel is, may be 1" at the wheel.
As noted yesterday the lower rod end is close to bind at 4" droop and the lower rod end is close to touching the spindle at full droop. Reducing droop travel a little will alleviate both those issues.

Aside from repaint of some front end parts the sway bar install is near an end. A test drive will be delayed a little because bump needs to be revisited. A much more elaborate evaluation needs to be done before the car rolls out the door. With springs and shocks and sway bar and calipers already off the car bump is easy now. Need to know what bump is doing when the car is turning. It's worth looking at that to see if there is a gain to be had with a little tweaking of the bump curve.
More on that later.
Bob

#1073942 - 05/19/22 09:04 PM Re: Front sway bar project [Re: mmc427ss]  
Joined: May 2002
Posts: 4,376
MAP Offline
15+ Year
MAP  Offline
15+ Year
Member

Joined: May 2002
Posts: 4,376
Yuma, AZ
So, if straight-ahead bumpsteer is perfect but bumpsteer with steering isn't, what are you going to do about it?

Last edited by MAP; 05/19/22 09:51 PM.
#1073956 - 05/20/22 10:46 PM Re: Front sway bar project [Re: mmc427ss]  
Joined: Jan 2000
Posts: 5,581
mmc427ss Offline
20+ Year
mmc427ss  Offline
20+ Year
Member

Joined: Jan 2000
Posts: 5,581
Pottstown, Pa
Never stated that straight-ahead bumpsteer was perfect, very good for straight ahead but not near perfect. Few old vehicle and hot rods are near perfect, maybe some of the new stuff is perfect.

The goal for checking the bump at the 20 degree in and out each side is to see exactly what the wheel/tire is doing as it moves through 1 1 /2" compression to 1 1/2" droop. There is no need to go nuts on doing the full range of full compression to full droop at 20 degrees as the new bar setup will limit high speed cornering to a much smaller range of suspension movement.
I feel if the inboard tire is toeing in (droop) and the outboard tire is toeing out (compression) at 1 1/2" at 20 degrees there could be an area to improve upon. Until I see what is going on no verdict can be reach.
Being I'm stubborn and will continue using the stock steering linkage as in not wanting to go to rod ends for tie rods or drill spindles steering arms to use bumpsteer adjustment kits the means to a change in bump is via the inner toe rod position on the centerlink. That is where I lowered the stock inner tie rod position 3/4" to arrive at good bump numbers prior. Also the 9 3/4" degrees caster now available had a huge effect on the height of the outer tie rod end which netted the very good bump number on the current setup. I just feel there is more to look at in terms of improving the wheel positions at 20 degrees turning via the centerlink tie rod position. A new Moog DS909 centerlink is laying under a bench just in case.

Both LCA had trimming of steel done to improve access to the shock adj knobs, two coats of gloss black Rustoleum Prof on Weds, new letters C and R stuck on the bottom of the arm to indicate Comp and Rebound knobs (blind people need help laying under a car to know which knob is which) and the near 25 year old Global West del-a-lum cleaned, greased and reinstalled in the arms. Love them bushings, they never wear out and ZERO bind.

Installed the LCA last night and check the lower rod end to spindle clearance at full droop, good to go now. But made 3/16" thick 1" x 1 " steel pieces to be welded to the frame to reduce droop travel. Quick measurement of the upper arm and the ratio is near 2:1 for the bump stop. Measurement at the end of the spindle stub shaft showed it reduced droop by 3/8". SCORE!!!. That mod will insure at full droop the lower link rod end will not go into bind.

On each side of the rod ends, both top and bottom a QA1 stainless steel .250" rod end safety washer was being used. On the bottom mount one on each side just filled the space on each side of the rod end, that mount is in double shear. On the top rod end is a safety washer on each side. The outer is needed as a rod end safety washer which prevents the rod end from coming off the bolt if the rod end comes apart. The washer between the rod end and the sway bar arm is just used as a spacer. When the link angle inboard was check I found if that .250" thickness of the QA1 spacer is reduced to .180" the angle of the of the link is reduced to near 0 degrees at ride height. So off to the belt sander and some clever holding of the spacer and was able to finish at .180". The other option for a spacer was to go see my machinist friend and have it make me two spacer like that. A little patience and a container of water as a coolant and the spacers turned out great. That 4.2 degree cant that was put into the link end of the arms is huge in allowing the link to not have any issues with touching the arm. Just hard to show, explain, how well that worked out as the suspension moves through full travel. May need to take a video of how nice all that really worked out.

The lower, bottom, rod end is the female and because of the need to have the link mount in the "valley" of the LCA it has that negative (caster) angle. There was nothing i could do about getting that angle close to zero as the mount could only go in one place. If i had made the arm length 8" instead of 7.75" that would have reduced that angle a good bit, but sacrificed bar rate in the process. So it was the compromise, some angle and a higher bar rate. When the car is back on the ground and set at ride height will be able to do final link angle measurement to see just how much angle there really is on the link.

So sway bar fabrication is all but done. Will do the bump checks this weekend and then work on getting this car back on the ground and out the door for a test run. As with all good things taking time this dragged on for nearly a year. It was last June when Iran my first autodx with the new wheels and 200 tires and lance started to beat my ear about a big bar. It was right after Christmas when this project got to the phase of shopping for parts and seeing if a very high bar would fit the confines desired. So 5 months and finally almost ready to test the theory.

Will have some pics posted of the final install very soon.
Bob

#1073957 - 05/22/22 03:02 AM Re: Front sway bar project [Re: mmc427ss]  
Joined: Jan 2000
Posts: 5,581
mmc427ss Offline
20+ Year
mmc427ss  Offline
20+ Year
Member

Joined: Jan 2000
Posts: 5,581
Pottstown, Pa
Despite being a record high temp today, 95, managed to get some stuff done on the car.
Was happy with the 3/16" pads to shorten the droop travel and welded and painted them in. Done. Droop travel now is just shy of 3 1/2" from ride height.

Pull the jackstands and replaced them with solid blocks of concrete block /wood and shimmed to arrive at body ride height without the wheel and tires. Installed the rotors and mounted the bumpsteer gauge setup, wheel studs hold it in place. Once you know where the spindle is at ride height you zero the gauge height to that position. It's been near 4 years since playing with the bump gauge setup so it takes a little relearning to get the process dialed in to get good numbers.

Made numerous checks of bump from ride to 2" compression and ride to droop of 3" on the left side of the car. The straight ahead bump is very good and only changes .075" from ride height to 1 1/2"compression, and from ride to 2" droop .022". Many years ago before playing with bump correction on a B spindle it was near 3/4" toe in, one side, at full droop. Man it's come a long way since those early days.

Ran 20 degree in and out 20 out through full range and realized i may have erred in what i was seeing. If it was 95 outside the shop was warmer and think my brain got a little fried. But i do know now the procedure to check straight, 20 in and 20 out through full travel can be easily measured. When i get back to the shop, maybe Mon, I will perfect the setup and be able to see exactly what the toe change is.
Today was just familiarizing with getting accurate bump numbers on that part of a not to stock front suspension. Next time out will be able to put good numbers on paper so I can see what is happening to bump as the car is hard cornering left and right. Looking for toe out in droop at 20 degrees to see if bump out may help the inside tire.
Bob

#1073963 - 05/23/22 02:54 AM Re: Front sway bar project [Re: mmc427ss]  
Joined: Jan 2000
Posts: 5,581
mmc427ss Offline
20+ Year
mmc427ss  Offline
20+ Year
Member

Joined: Jan 2000
Posts: 5,581
Pottstown, Pa
Managed to find time this morning to do the left side of the front suspension now that i have good technique to do all three zones. Here's a couple pics that Lance has hosted for me.
First is the bump gauge setup doing a 20 degree turned out on the left side of the car. This bump gauge setup is a home made, some could say almost a copy cat, but is very accurate once the setup is is done correctly. Will measure to .001" via a dial indicator.
https://lancehamilton.smugmug.com/Other/i-22DF6rt

Next pic is the measurements taken this morning on the left side of the car. Tomorrow should have time to jump over to the right side of the car and run all the same tests. These are not the first set of numbers run, might be the 4th time they were run but can say + or - .010" was the deviation. And I'm certainly not going to worry about .010" variable. These are good number for my car.
https://lancehamilton.smugmug.com/Other/i-mFH65Xj

My interpretation of those numbers is the straight ahead bump is very good through the entire range of wheel straight ahead, 2" compression down to the 3 1/2" of droop. When I think back to when I started to develop this B spindle swap into something livable the bump at full drop was .750" each side. The centerlink and the caster change to 9.75 degrees together netted those numbers. There is really no room for improvement, or need. Most would trade there 2nd born for a bump curve like that on an A or G body.

My focus on the 20 degree in and out bump checking is to see when, how much and whether the wheel will toe in or out at compression or droop. On the left of the spec sheet is 20 degrees OUT on the left wheel. On a hard corner to the left that wheel is droop, maybe 1" to 2' droop. Circled is the droop numbers, at 1 1/2" .220" toe OUT. This is what i wanted to see, the wheel toeing out, adding Ackermann to the left drooping tire.

Now looking at the same left wheel when it is in the 20 degree IN position, this is still the same left wheel, that wheel would be in the compression state and the car is turning right. Looking at the number in the circle, compression, at 1 1/2" compression there is .150 toe OUT.

My thinking is when the that left side wheel is used as the outside wheel/tire on a corner, turning hard right, at 1 1/2" of the compression the wheel is toeing out .150", so the steering wheel/driver would then compensate for the added toe out apply less angle manually to the wheel. And now at the same time the inside wheel is going in droop at 1 1/2" and adding toe out of .220".
So realistically at that right turn you have added .370" (.150" + .220") toe out when you are turning high G to the right.

Couple notes about what I think i see.
My car has very little Ackermann when checked at ride height on the alignment rack. One side is 1 degree at 30 degrees and the other side is like 1 1/2 degree. at 30 . Something I considered for an autox goal was to increase itoe OUT on the inside wheel. After looking at the amount of toe out that is added at the correct time I see no real need to add Ackermann at the static of ride height.

The front tires on the car after 30 hard autox runs looked very good, no real sign of graining which is good.
Last year the turn in of this car was exceptional, no front pushing, plowing, squealing, i was more than happy with it.

I know the means to change anything on the bump measurements means a new centerlink would be tried. But know any change to the height of the inner tie rods would effect the straight head bump. messing with straight bump would be silly. The only thing that could be done there is an adjustment up or down by 1/16" from the 11/16" drop build into the inner tie rod now. If you notice the bump on the straight ahead is .075" OUT at 1" compression, 0 at ride height, then droop measurement is .005 IN at 1", .007" OUT at 2". A tweak would move that .005" IN closer to the 0 and increase the compression toe out .005" OUT. We ain't worried about a couple thousandths.

As cheater Ackermann I've been running about 1/8" give or take toe OUT as the static toe setting. The new RT660 are really almost a slick and they just don't track as nice as a treaded tire, especially with toe OUT and -1 1/4 degree camber. Now that i can see a lot of toe OUT is being added at 20 degrees in and out I may back off the toe and setup for a zero toe.

Will check the right side tomorrow through all the bump checks and make a decision to not touch the bump if it mirrors the left side.

Here's a pic of the sway bar link in it almost final install. All the fab is done, just need to bolt the arms and links in when the springs, shocks go back in the car this week. Link final length and whether the link end of the arm is level at ride height has yet to be finalized. Other than that 6 months of toil may be coming to a close.
https://lancehamilton.smugmug.com/Other/i-pvt7QN2
Bob

#1073967 - 05/23/22 05:32 PM Re: Front sway bar project [Re: mmc427ss]  
Joined: Dec 2007
Posts: 6,600
SSLance Offline
10+ Year
SSLance  Offline
10+ Year
Member

Joined: Dec 2007
Posts: 6,600
Peoria, AZ
[Linked Image]

[Linked Image]

[Linked Image]


Lance
1985 Monte Carlo SS Street Car
#1073968 - 05/23/22 05:35 PM Re: Front sway bar project [Re: mmc427ss]  
Joined: Dec 2007
Posts: 6,600
SSLance Offline
10+ Year
SSLance  Offline
10+ Year
Member

Joined: Dec 2007
Posts: 6,600
Peoria, AZ
I think the bump #s look great, set the static toe at 0 and send it. It'll track awesome and turn in will still rock.

Is it done yet? laugh


Lance
1985 Monte Carlo SS Street Car
#1073969 - 05/23/22 07:36 PM Re: Front sway bar project [Re: mmc427ss]  
Joined: Feb 2020
Posts: 679
88ssBrent Offline
Member
88ssBrent  Offline
Member

Joined: Feb 2020
Posts: 679
Friendsville
Looking good Bob!

#1073976 - 10 hours ago Re: Front sway bar project [Re: mmc427ss]  
Joined: Jan 2000
Posts: 5,581
mmc427ss Offline
20+ Year
mmc427ss  Offline
20+ Year
Member

Joined: Jan 2000
Posts: 5,581
Pottstown, Pa
Busy the past couple days trying to wrap up this project and get some miles on the new setup.

Took the time to run all the toe number both sides of the car, straight, 20 IN and 20 OUT with i feel very accurate results. Once you establish a bump test procedure and use it for all 6 checks and do them repeatably getting the numbers is easy. From side to side slight variances but close enough to say the sides mirror each other.
I'll see if someone will host a couple more pics for me. One is a chart of those bump numbers, and how they interact as the car front end goes into roll. I learned exactly what i need to know. At this time no changes will be made to those bump profiles.I like what i see for now and may adjust at a later time, but can same tickled they are that good.
Years ago i saw a video of a NASCAR chassis on a chassis simulator/dyno. All kinds of sensors could measure and monitor all the 100 different movements of the pieces. Some computer could take all that info and make the chassis better. Way cool, just not something us bench racer have access to. We do the best we can
with less tech.

Monday morning finished all the measuring and started the process to get tires back on the ground. LCA, springs, shocks, bump stops, splash guards reinstalled late evening.
Today it was service and reinstall the brakes after repacking wheel bearings and greasing entire front end. Love the front brake package on the car, Stop Tech 1LE rotors, Wilwood D52 calipers and Hawk HPS pads. A lot of life left on the pads but the damn steel anti squeal plates they glue to the back of all four pads were falling off the back of the pads. I've had this happen on other pads didn't expect it with the Hawk. So pulled all those plates off and hoping they aren't to noisy. May just replace the pads soon but no recourse but to reinstall today.
Got out a fresh qt of brake fluid, sucked out the fluid in the master a gravity drained a 1/2 qt through the bottom and top bleeder in the calipers. Almost everything in this system is stainless so you don't get much dirty fluid. It's just good to change it, especially if you got the pads/piston in the calipers retracted.

Upper rod end is attached to the arm via a 1/2-20 thread 3/4" deep. Once the male and female threads were clean a drop of blue Locktite on the threads and torqued to 60. A 1/2" of bolt protrudes from the backside of the arm and a Jetnut is used a a locking fastener, 40 lbs.

With everything back together, tires sitting on the turn plate and car back to ride height it was time to set up one sway bar arm and link. The goal was the link end of the arm to be near level, 0 degrees. Another goal was links as long as possible. I knew from watching the link articulation that at full droop the link would benefit if the level section of the arm was point upward at a small angle. With the arm and link installed at ride ht a 2.5 up angle would net a 3 5/8" link length so that compromise was made. Was hoping for 3 3/4' or more but 3 5/8 is OK.
So the left side arm pinch bolt tightened and the lower link bolt installed and snugged.

Next is go the right side and verify that it has the same 2.5 degree up arm angle as the left side. The link length is set at 3 5/8", same as the left link, before the pinch bolt is tightened. Now is when things get difficult, fought getting that lower link rod end aligned so the 1/2" bolt and spacers can be installed. A big royal PITA. With the car sitting on the ground at ride height that link was shortened 1 1/2 turn, .075" still had a tough time getting the bolt to pass through the mount. A bottle jack was then used at the #2 R body mount to raise the car a hair, this changed the load at just that corner enough pass the bolt all the way through.
That took a lot longer than expected. But it also put some perspective on how much a little up or do on one side will produce an immediate response on the other side. This bar setup is a solid coupler now. The old bar had 8 urethane bushings to soften the hit , and was easy to compensate for minor chassis loads side to side.

With any luck will make a trip to the gas station to top off the tank and settle the front suspension tomorrow afternoon. Back in the shop and another once over all the bolts and check the arm angle and also get a true reading of the link angles at ride height. Will also get my toe gauge working to check toe change via a tape measure from ride to full droop, easy to do. Need to just see for S&G that a dial indicator and a tape measure use the same 1" .

A whole lot of guesstimating and modeling and time goes into trying to end up satisfying the expectations. I do love it when a plan comes together.
Oh, ran out of Lava soap, time to end this project.
Bob

#1073979 - 3 hours ago Re: Front sway bar project [Re: mmc427ss]  
Joined: Dec 2007
Posts: 6,600
SSLance Offline
10+ Year
SSLance  Offline
10+ Year
Member

Joined: Dec 2007
Posts: 6,600
Peoria, AZ
It's gonna be awesome!!

Congrats!!


Lance
1985 Monte Carlo SS Street Car
Page 12 of 12 1 2 10 11 12

Random Images
500/thumbs/p8210021.jpg
by zombiedeth
523/thumbs/DSC_0664.jpg
by Z65_Paul
500/thumbs/IMG_5889.JPG
by BAD ASS 87
500/thumbs/DSC_0036-1.jpg
by Mikep
760/thumbs/tn_monte_carlo_008.jpg
by bug
Help MonteCarloSS.com


Recent Contributors
86BlackSuperSport
dns87ss
Authorized Vendors
Tell them you saw it
on MonteCarloSS.com!


CustomMonteSSParts.com
Dixie Monte Carlo Depot
GSI Interiors
HRpartsNstuff
Mikes Montes
Savitske Classic & Custom
Powered by UBB.threads™ PHP Forum Software 7.6.0