Topic: Camber

First post in a new category.

Sure we can talk about camber but mostly this was the only category that didn't already have a post.

Lemons has it own forum.  This is kinda scary.

Troy

Troy

#35 LRE
1973 Datsun 240Z

Re: Camber

I need to fab up some camber plates for my car this week...

To finish first, first you must finish. -Rick Mears
Pandamonium Racing

Re: Camber

I've been looking to pick up one of those fancy new digital cambers soon...

Not Too Sharp Racing
1969 Datsun Roadster/S10 Hybrid
4.3 V6. TH350 Slush-O-Matic
Rusty, slow, unreliable, shoddily built.

Re: Camber

We made up camber plates for our Volvo, and the camber bolts were too short!  Make sure you use bolts that are long enough, or they'll pull out during the race.  You want thread engagement length at least equal to the diameter of the bolt.

Tunachuckers: 13 Years of Sucking at Sucking
2008- 2010:  1966 Volvo 122, "Charlie"
2010-conversion into Plymford:  1975 Ford LTD Landau...doesn't have a name?
2018:  1950 "Plymford".  Organizer's Choice - CMP Fall 2018 Hurricane Florence reschedule

Re: Camber

laz wrote:

I need to fab up some camber plates for my car this week...

Fab up? We just slotted the holes in our strut towers. In fact we went a little too far and had to weld some metal back in, heh.

The Homer: Powerful like a gorilla, yet soft and yielding like a Nerf ball.

Re: Camber

Laz,

I race a 240Z.

I would like to have camber plates but they are expensive.  The spherical bearing holder and bearing itself is where it gets expensive.

I made adjustable lower control arms instead.  Moving the bottom out got us more camber and a wider stance.

The adjustable lower arms were easy enough to make.  Once that was done, we needed to lengthen the compression rods.  We shimmed the stock ones with washers but we are maxed out now to get our caster back in range.

After all that, our tie rods were about out of threads.  I got out a Moog book at the parts store and started looking at other options.  I started by looking at other Z cars models.  I used a set of used 280ZX outer tie rod ends which are about 3/4" longer than the stock part.  I also had to change the left hand threaded inner tie rod on one side to a right handed thread one to use 280ZX outers.

While there ended up being more additional complications than I expected.  It works and cost about $6 a side to make the adjustable control arms.

I'll try and post the pics.  May have to be in the pics section.

Troy

#35 LRE
1973 Datsun 240Z

Re: Camber

In the second Altamont event our '87 Honda Accord had heavy contact with a several cars (who didn't) namely a Hearse. It gave us a bunch of unplanned negative camber in the rear and seriously improved lap times. I was stunned. I'm actually thinking about putting it in the wall in lap one to see if I can get the same results. Suspension tuning by braille.

Re: Camber

Troy's method of adjusting the control arms (if you have a car with suitable hardware) works really well, and it can be free--on our car, we slotted the mounting points to effectively make the top arms shorter, thus creating negative camber--total cost $0.

Re: Camber

Another non-adjustable way is to simply slice the a-arms and remove or add material, re-weld and go. Not so adjustable, but effective if you've got a competent welder on the team.

maybe I shouldn't be suggesting this, maybe we'll see 20 front suspension failures during the next race. If you happen to be running a 105 series Alfa Romeo, this works really well however.

Re: Camber

Yeah, we just drilled another set of holes in the strut tower of the ol' Cavalier and voila, instant camber. FWD cars seem to like 2-ish degrees of negative camber for faster lighter steering with none of that pesky 'stability' to worry about like in your boring old street car...

Volvo PV544 - now with Chevy 3.9 power!
2007/2012/2013 Driver's Championship (what was I thinking!?) 125 races and counting
9/30/2022

Re: Camber

Jeff_LeMonsHQ wrote:

Another non-adjustable way is to simply slice the a-arms and remove or add material, re-weld and go. Not so adjustable, but effective if you've got a competent welder on the team.

maybe I shouldn't be suggesting this, maybe we'll see 20 front suspension failures during the next race. If you happen to be running a 105 series Alfa Romeo, this works really well however.

That's why I said we "slotted" them. Sounds safer, right? But, yeah, if you're fabbing parts in this fashion, to make sure you know what you're doing, please....

Also, this topic should really be in Lemons Tech. Lemme see if I can move it....

Re: Camber

Nick,

I only mentioned camber cause I didn't have anything else to say and just wanted to make the first post in a section.  Then a discussion broke out.

Everyone Else,

I would have liked to just slot the holes in the top of our strut tower but there isn't enough room to pull them in unless you enlarge the tower.

Since we have McPherson struts, there are no upper control arms.

My first attempt at camber was to chop a lower control arm and extend it about 1/4".  I welded in a piece of scrap brake rotor, totally free.  It was better but still not enough and you are just taking stabs in the dark. 

I chopped the control arm and welded in a 3/4" threaded insert.  That could be used with a hiem joint.  That was going to require a bunch of shimming to center it up in the correct alignment.  So I decided to make a bushing holder and could have cut down the remaining piece I cut off.  Turns out our roll cage tubing was almost the exact size for the bushing.  So I cut down a piece of scrap tubing, welded on a 3/4 fine thread bolt, then reinforced that with a piece of notched tube around that.

Try this for a pic: http://groups.yahoo.com/group/24hoursof … mp;dir=asc

The big question was whether they were strong enough.  We raced in February on them, no problems.  Our previously favorably bent right strut assembly started to come apart and we got bumped a bit on both sides and both lower control arms were fine. 

Our car did not go flying in February like October so I don't know how well they will do on a ramp test.

We are happy with them and I am supposed to make another set for my friend.

Troy
1973 Datsun 240Z

Troy

#35 LRE
1973 Datsun 240Z

Re: Camber

X-args wrote:

Yeah, we just drilled another set of holes in the strut tower of the ol' Cavalier and voila, instant camber. FWD cars seem to like 2-ish degrees of negative camber for faster lighter steering with none of that pesky 'stability' to worry about like in your boring old street car...

And this is the car with more Lemons races under its belt than any other in history! What is the total, six?

Re: Camber

"And this is the car with more Lemons races under its belt than any other in history! What is the total, six?"

If it's got 6, I'm impressed! 

We've got 4 on the World of Outlaws / Team 31 Miata - Altamont 07-1; Altamont 07-2; Altamont-08; and, T-Hill-08.  Second engine but everything else is just as we got it (with 245,000 miles on it).

6 Lemons events begas the question: How many major replacement parts?  Engines?  Trans?  Others?

John

"Age only matters if you're a cheese."  Helen Hayes

15 (edited by rnr 2009-05-02 06:24 PM)

Re: Camber

We used a strut bender to add camber after we encountered severe tire wear at Altamont 07.

http://www.rahulnair.net/blog/2007/11/0 … ace-setup/

The car has since done 4 races with a best finish of 10th place at TH 08.

Team Formula BMW
Finishing order: 44th, 44th, 19th, 10th, 5th, 10th, 5th
We will win some day smile

Re: Camber

MurileeMartin wrote:
X-args wrote:

Yeah, we just drilled another set of holes in the strut tower of the ol' Cavalier and voila, instant camber. FWD cars seem to like 2-ish degrees of negative camber for faster lighter steering with none of that pesky 'stability' to worry about like in your boring old street car...

And this is the car with more Lemons races under its belt than any other in history! What is the total, six?

Yep.
Altamont 07a
Detroit 07
Altamont 07b
Thunderhill 07
Altamont 08
Thunderhill 08

It might be out at the Buttonwillow race if we don't get the second '87 Cavalier sorted/shipped back in time. It's pretty beat body wise, but the mechanical stuff is still good, rear wheel bearings aside...

It goes good for a J-car.

Volvo PV544 - now with Chevy 3.9 power!
2007/2012/2013 Driver's Championship (what was I thinking!?) 125 races and counting
9/30/2022

Re: Camber

professional.dreamer wrote:

"And this is the car with more Lemons races under its belt than any other in history! What is the total, six?"

If it's got 6, I'm impressed! 

We've got 4 on the World of Outlaws / Team 31 Miata - Altamont 07-1; Altamont 07-2; Altamont-08; and, T-Hill-08.  Second engine but everything else is just as we got it (with 245,000 miles on it).

6 Lemons events begas the question: How many major replacement parts?  Engines?  Trans?  Others?

John

I would NEVER 'begas' the question...
Major replacement parts: 1 rebuild of the original transmission.
Minor replacement parts:
Lots of bodywork, 1 radiator relocation (after the 07 Detroit demo derby),
1 strut, 1 front wheel bearing, 1 pick your part rear shock, 1 halfshaft,
1 rear axle beam, and now 1 rear wheel bearing assembly +
pulling the roof up enough to put another @#$& windshield in it...

Volvo PV544 - now with Chevy 3.9 power!
2007/2012/2013 Driver's Championship (what was I thinking!?) 125 races and counting
9/30/2022

Re: Camber

X-args wrote:
MurileeMartin wrote:
X-args wrote:

Yeah, we just drilled another set of holes in the strut tower of the ol' Cavalier and voila, instant camber. FWD cars seem to like 2-ish degrees of negative camber for faster lighter steering with none of that pesky 'stability' to worry about like in your boring old street car...

And this is the car with more Lemons races under its belt than any other in history! What is the total, six?

Yep.
Altamont 07a
Detroit 07
Altamont 07b
Thunderhill 07
Altamont 08
Thunderhill 08

It might be out at the Buttonwillow race if we don't get the second '87 Cavalier sorted/shipped back in time. It's pretty beat body wise, but the mechanical stuff is still good, rear wheel bearings aside...

It goes good for a J-car.

Are you going to turn it into a Cimarron? Please say yes!

Re: Camber

I think it depends on the car. 

We run about 2.5 - 3 degrees of camber on the 240Z which I think is also good for a Miata. 

We wear the inside of the tires way more now though.

Troy

#35 LRE
1973 Datsun 240Z

20 (edited by sawinatthewheel 2009-05-06 07:38 AM)

Re: Camber

There is another way to create more camber in a strutted car and that is to shorten the spring.  One can either cut the spring or, as John C. once described, heat up the spring enough so that it collapses on it self.  Maybe John C. can explain that process further.  Dropping a strutted car 1.75 to 2 inches will induce about -2 degrees.  This has the added benefit of lowering the CG.  If the budget allows, lowering springs are available from many online sites.

sawinatthewheel...sometimes too much, sometimes not enough...just like life

Re: Camber

Damn!  You guys are learning all the "Magic."  Well, "sawinatthewheel" is right...  reducing the hypotenuse of a triangle forces the increased angulation of the remaining sides. 

Yes, you can remove the coil and cut it, which shortens the spring, lowers the car and induces the camber.  This is a great fix for inexpensive lowering and camber.  However, the spring rate remains the same, so you may have a bouncy ride.  Watch for tire rub under heavy braking.  Also, make sure that you heat the last 3 inches of the cut coil and bend it inboard slightly so the coil sits in the perch.  Without bending the cut coil, it will spin and screw itself off the perch.

Better fix: leave the spring on the strut and resting on the perch.  Jack-up the car from under the A-arm.  Leave the jack under the suspension so the spring is always under pressure.  Using a large tip with a gas welder (cutting torch will work, too) slowly heat the second to bottom coil (NOT the bottom one), spreading your torch back and forth over 50% of the coil until the coil gets red hot.  The coil will start to deform and buckle.  Give the jack one pump to maintain pressure.  With practice, you can actually shape the deformation so it bends at 45 degrees.  Then do the same treatment to the coil above that, remembering to pump the jack with each coil treated.  If you do it right, it will deform and nest into the same shape as the lower coil.  Repeat on the next coil above that.  The number of coils treated depends on how low you want to go and how much camber you want to create.  This approach lowers the car, induces camber and has the added benefit of increasing the spring rate (which takes a little pressure off the shock and stiffens the car's suspension.)

Make sure that you have a bucket with water and a soaked rag handy to put out any small debris fires... like the rubber shock boot which always get fried.  Also, don't cook the brake line!  If this is your first attempt at this, make sure that you have a spare set of springs available... just in case your finished work looks like a Calder art sculpture.  It takes a little practice.

On a stock Miata coil, I treat 4 coils, which lowers the car 2.5" and gives me a total of 2.0 degrees of negative camber.  Afterwards, I also arc weld the collapsed coils together, then safety wire the coil to the bottom perch (to ensure that it doesn't slip out during rebound).

Depending on how you like you car set up, you may want to treat 3 or 4 coils on the front suspension springs and treat one less coil on the rear springs, which gives the car a little more suspension travel. 

There's more to setting up your suspension than just this, but that's still part of the "Magic."  There are pre-qualifications before I can teach "Magic."  Read my post on "Newbies Welcome at Reno-Fernley" to understand the "Magic."

If you're at Reno-Fernley and want to see the finished product, drop by our pit and I can explain it more in detail.

John

"Age only matters if you're a cheese."  Helen Hayes

Re: Camber

professional.dreamer wrote:

Yes, you can remove the coil and cut it, which shortens the spring, lowers the car and induces the camber.  This is a great fix for inexpensive lowering and camber.  However, the spring rate remains the same, so you may have a bouncy ride.  Watch for tire rub under heavy braking.  Also, make sure that you heat the last 3 inches of the cut coil and bend it inboard slightly so the coil sits in the perch.  Without bending the cut coil, it will spin and screw itself off the perch.

FYI, cutting coils off a spring increases the spring rate.

--Rob Leone Schumacher Taxi Service
We won the IOE at Southern Discomfort.
We got screwed at The Real Hoopties of New Jersey  and we took cars down with us.
We got the curse at Capitol Offense but they wouldn't let us destroy the car.

Re: Camber

Rob -

You are correct... it does alter (increase) the rate if you approach or reach coil bind.  I'm basing my statement on a stock OEM spring that was rated for the car's weight... and the fact that you would never cut off more than 20% of the total coil length (like 3 coils for a 14 coil spring).  That loss would be minimal in a rate increase... or, at the least, relatively unnoticeable to the driver.  The driver would probably feel the shock compression (reduced shock travel) more than the spring.  Cutting off half the coils would significantly increase the rate but make the shock unusable on the stock strut.  By collapsing the spring (via heat at 4 coils), I measured a 34% increase in spring rate on my spring/shock dyno.

"Age only matters if you're a cheese."  Helen Hayes

Re: Camber

wledswift wrote:

So how much camber are we talking here. Be serious now I do know the difference between 3 and 45 degrees. Any help will be much appreciated

Well if your into welding you should be able to make a car with almost 0 camber deflection going threw a corner, maybe 3 degrees max, however you'll need super tight used grease fittings or abandon spherical bearings, so good luck with that.  You should do it since i'm not going to (probably.)

25 (edited by troubleonwheels 2009-05-06 09:54 PM)

Re: Camber

professional.dreamer wrote:

Rob -

You are correct... it does alter (increase) the rate if you approach or reach coil bind.  I'm basing my statement on a stock OEM spring that was rated for the car's weight... and the fact that you would never cut off more than 20% of the total coil length (like 3 coils for a 14 coil spring).  That loss would be minimal in a rate increase... or, at the least, relatively unnoticeable to the driver.  The driver would probably feel the shock compression (reduced shock travel) more than the spring.  Cutting off half the coils would significantly increase the rate but make the shock unusable on the stock strut.  By collapsing the spring (via heat at 4 coils), I measured a 34% increase in spring rate on my spring/shock dyno.

The effect on effective spring rate is proportional to the amount of length removed from the unloaded spring relative to the original full unloaded spring length. 

An example:

If you have a spring wherein one 'coil' of the spring will deflect one mm with one lb, and the spring has ten coils, one lb will compress the spring 10mm.  If you remove two coils one lb now only compresses the spring 8mm and it requires more weight to achieve the same 10mm deflection, thus a higher effective spring rate.  When you cut a spring, you change its length and its rate, which is why springs are ordered on a basis of lb/inch and total length, or rated as lb/inch/inch.

Now, if you're heating the springs to collapse them and not utilizing excelent heat sinks further up the spring (i.e. lots of vice grips or the like to dissipate the heat and not let it travel the full length of the spring) you're actually changing the metallurgical properties of the spring and your results will be unpredictable.  One thing I can say for sure, if you're heating coils to collapse them and not cooling the spring after, you are decidedly decreasing the spring rate as you are softening the metal.  If you are throwing water on them at some point, who knows what you're doing to the metal.  Heck, it might become very brittle and break mid-race (or as you're loading it on the trailer)!

One more thing on this subject: if you have old struts/springs, you will likely see a great increase in ride quality and stiffness when lowering a car via cut springs because all the internal pressure seals in the damper are now riding on new surfaces and will seal better.  No more groves cut and loose tolerances where millions of little bumps have worn them in = newish strut.  The seals are still old and it's still leaked out half its fluid, but it will be better than before.

Here is another massively misunderstood topic:

As to camber gain, this is ENTIRELY subject to the vehicles suspension geometry, in particular the lower a-arm on a McPherson strut assembly.  The lower arm in a McPherson strut essentially acts in an arc around the body-side mount, and the strut pivots about the top mount.  See here:

lower a-arm motion

As you shorten the strut (lower the car) the a-arm comes up in its arc to the point where the lower ball joint and body-side mount are in line making the a-arm parallel with the ground.  Up to this point you have 'gained negative camber' as the tire is pushed outward while the upper pivot stays fixed, effectively making the lower arm 'longer' relative to the upper mount.  Beyond this point you LOSE CAMBER.  So it is possible to gain camber by lowering a car, but it's also possible to lower it too much and lose camber.  And we're talking STATIC CAMBER here, too.  As an example, if you lower most mid-90's Subarus only 2", you've just gone past the point of parallel and have begun to lose camber beyond what can even be adjusted for.  So much for helping handling by lowering the car.

But, lets say all is great and you've lowered your car, and the alignment machine or bubble level or your eye says you have 3 degrees camber.  Congratulations, your STATIC camber (sitting still) is huge and you can brag to your friends.  Now, turn.  If you've got that lower a-arm near parallel (or worse above), as the body weight transfer compresses the suspension that a-arm goes above the parallel point pulling the tire back into the body relative to the upper strut mount and loses camber as you corner on to the tire, exactly what you don't want to do.  All the precise static camber adjustment in the world isn't going to do a hill of beans (except wear out the inside of your tire) if you lose all of it as soon as you turn. 

In this case, the only thing you've done (and the reason most people who do this kind of lowering think they've greatly improved their handling) is stiffen your springs, which makes the car FEEL like it's not wallowing all over the road, feel like a go-cart.  In reality, it'll probably plow way faster than it used to, and most people make their suspension so stiff the tires end up hopping and losing traction anyway.  Just my .02 on stupidly lowered cars.  Yes, my DD is lowered 1.5".

This is the inherent weakness in a McPherson assembly, and the reason they're looked down upon as compared to multi-link or dual wish bone which can compensate for more negative camber and even toe-in during dynamic loading such as turning.  So why do people use McPherson?  The answer is obvious = it's cheap to build, cheap to install.

If you are really interested in improving the handling alone, the right thing to do is cut your springs to a reasonable rate (go ahead, re-install and drive until you find a good stiff feel), then fabricate spacers for your strut top to put the lower a-arm back into the geometry-correct position, or one at least near it (I understand the desire to lower the car a bit to look less like a tool in your bitchin camaro).  The other option is to modify the lower a-arm mounting position so it is higher.  Either way you'll get the strut-rejuvenating properties, stiffer springs, and reasonably correct geometry.