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Old 04-02-2011, 06:54 PM   #1
iwannadrive
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Default 240 Performance Alignment Specs?

Just wondering what you guys run, and also I suppose what techniques you use to measure the toe, on these things.

I have my camber maxed out on the stock strut mounts and strut towers, and pretty soon I'll throw on a set of widened control arms and tie rod ends (I know - ghetto, but it was before I realized camber plates would be a better use of my money) for moar camber and caster. Mainly I'm just wondering what you guys run for toe specs. This is my daily driver, but I autocross it and drive it pretty hard too

Some relevant specs on my car:

'83 Volvo 244 Turbo

- 15x6 ET25 Virgo wheels with crappy 195/60 no-seasons
- basically stock suspension minus 1.5 coils in the front (soon to be a little lower in front and rear)

stuff coming soon:

- good bilstein or decarbon struts coming sometime in the next few weeks (can't complain for free!)
- ~1/2 inch widened control arms going on as soon as I get new CAB's (with new ball-joint holes for moar caster)
- wagon rear springs cut to slight rake
- 16mm wagon rear swaybar
- 23+21mm dual front sway bar setup with new bushings
- nearly new 195/55/15 star specs on the virgos
- probably will also weld up a strut brace and strut-to-firewall braces as well, and possibly a lower "cherry turbo" type brace sometime soonish too.
- possibly/probably coilover sleeves with 250ish # springs too, depending on what I can find for cheapish

I'm thinking I might try 1/16 or 1/8th inch of toe-out up front for more rotation and better turn-in.

Thoughts? What worked best for your 240?

Also, how did you measure toe on your 240? I'm having trouble wrapping my head around this.
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Old 04-02-2011, 07:00 PM   #2
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Buy new 205/50/R15 tires.

You can have the best suspension in the world, without traction, it's crap.
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Old 04-02-2011, 07:14 PM   #3
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nearly-new 195/55 star specs are pretty great tires, and 205-width tires won't have any real edge on good 195's, since the shoulders aren't supported as well by the rim (it's only a 6-inch wide wheel).

however, this thread is about alignment settings. not tires.
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Old 04-02-2011, 07:23 PM   #4
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2+ degrees negative camber, 3+ degrees caster and toe, well that's a matter of opinion on these cars. I have run it in 1/16", zero, and now out 1/16". I like it out for my car, but your results may vary as I have a totally different setup from you.
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Old 04-02-2011, 07:24 PM   #5
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2+ degrees negative camber, 3+ degrees caster and toe, well that's a matter of opinion on these cars. I have run it in 1/16", zero, and now out 1/16". I like it out for my car, but your results may vary as I have a totally different setup from you.
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Old 04-03-2011, 12:08 AM   #6
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For a daily driven car, around -1.5deg camber is a nice compromise. That's what I run with 205/60 all seasons on 15x7. -2 or more is preferred for max performance on street tires.

I usually set toe to slight toe-in (at most, zero). Toe-out can help turn-in, but it won't cure understeer, and it will rapidly wear the inner edges as toe-out increases.

Caster, as much as you can get, if you have any adjustment here.

-2 camber, 215/45/16 Hankook RS2 on 16x7. 700lb front springs and IPD 25mm front bar keep the nose fairly flat.
http://www.pbase.com/towerymt/image/131577783/original
http://www.pbase.com/towerymt/image/131577768/original

To set toe, you need plates held against the tires. They need to be above the base of the tire because the tire bulges out at the bottom. Ideally you'd mount plates to the wheels, but against the tires will work. I use a board along each front tire, held against the tire with a spare tire. You're measuring the distance between the plates behind the tire and ahead of the tire. If these measurements are the same, then the tires are parallel, and thus zero toe. If there's a difference, it's either toe-in or toe-out. Measure as close to the tire as possible. This method can let you set toe close enough that the tires aren't wearing odd or fast, and you can make changes quickly and test the change.
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Old 04-03-2011, 03:06 AM   #7
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Originally Posted by badvlvo View Post
2+ degrees negative camber, 3+ degrees caster and toe, well that's a matter of opinion on these cars. I have run it in 1/16", zero, and now out 1/16". I like it out for my car, but your results may vary as I have a totally different setup from you.

How are you adjusting caster?
The only way to do that (that I'm aware of) is by switching from power steering ball joints to manual ball joints, and vice-versa.

IIRC the difference is like 3.5 vs 3, respectively.
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Old 04-03-2011, 11:31 AM   #8
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How are you adjusting caster?
The only way to do that (that I'm aware of) is by switching from power steering ball joints to manual ball joints, and vice-versa.

IIRC the difference is like 3.5 vs 3, respectively.
Adjustable upper mounts (camber plates). Or shim the rear of the control arm, but I don't think anyone does that. Adjustable control arms would allow it too.
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Old 04-03-2011, 02:12 PM   #9
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For a daily driven car, around -1.5deg camber is a nice compromise. That's what I run with 205/60 all seasons on 15x7. -2 or more is preferred for max performance on street tires.

I usually set toe to slight toe-in (at most, zero). Toe-out can help turn-in, but it won't cure understeer, and it will rapidly wear the inner edges as toe-out increases.

Caster, as much as you can get, if you have any adjustment here.

-2 camber, 215/45/16 Hankook RS2 on 16x7. 700lb front springs and IPD 25mm front bar keep the nose fairly flat.
http://www.pbase.com/towerymt/image/131577783/original
http://www.pbase.com/towerymt/image/131577768/original

To set toe, you need plates held against the tires. They need to be above the base of the tire because the tire bulges out at the bottom. Ideally you'd mount plates to the wheels, but against the tires will work. I use a board along each front tire, held against the tire with a spare tire. You're measuring the distance between the plates behind the tire and ahead of the tire. If these measurements are the same, then the tires are parallel, and thus zero toe. If there's a difference, it's either toe-in or toe-out. Measure as close to the tire as possible. This method can let you set toe close enough that the tires aren't wearing odd or fast, and you can make changes quickly and test the change.
Thanks for all the info, man! I'll see if I can use the board idea later today... I was going to build some plywood jigs to mount on the lug studs and measure from those, but I ran out of time. I'll probably finish building those sometime later.

Also, just wondering, I remember back awhile ago a thread where you made some ghetto 'coilovers' with just some 2" PVC pipe acting as a bushing to keep a 2.5" spring centered. I believe you had something like 250# springs on DeCarbons - How did that handle for a street setup? I know that 250# is pretty soft, but I'll be getting some decarbons for free next weekend, and that's probably about all they can handle. Would the body roll be very excessive with ~250# springs and the equivalent of about a 26.5mm front bar?

As far as alignment, I ended up trying something like this:

http://www.negative-camber.org/jam14...alignment.html

but I think the panhard bar messed things up for me... I don't know. I gave it 1/16th inch of toe-out on both sides, measuring from the strings, and now it pulls pretty hard to the right, and the steering wheel is off center (to the right) when going straight. If I force the steering wheel straight, it pulls left. Hmm.

Also, what I noticed is that the alignment as it was before I touched it tracked pretty straight, but the left tie-rod had only about 2 threads showing between the flats and the rod end, while the right had about 6 or so threads showing. Pretty sure the car hasn't ever been in an accident, but I guess I don't know for sure.

To get the alignment where I have it now, measuring 1/16 in of toe-out from the strings, I turned the left tie rod out a couple turns so that about 4ish threads are showing now, and gave the right tie rod about a half-turn to a full turn. I think I've got a lot of re-measuring and re-aligning to do today. Haha. I'll probably try clamping some boards onto the tires for today, and if that comes to no avail, I might just return it to about how it was, with 2 threads showing on the left, and 6 on the right. Maybe.
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Old 04-03-2011, 02:13 PM   #10
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Oh, also... Does the 240 front suspension change toe values when compressed through it's travel range? And if so, how? Is it affected by caster or camber?
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Old 04-03-2011, 09:30 PM   #11
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It is effected by camber for sure, set the camber first. I never paid attention caster since it isn't adjustable on all my stock junk. I've alligned like towerymt said but I'm lazy and bought longacre racing toe plates (they were cheap) and use a digital level for camber. Haven't done the 240 yet but have done Rabbits and other old stuff, will hit the 240 this week soon as I get tires for it.

FYI, I've done the string method, and it can be very accurate, but it's allll in the setup, and it's a time consuming PITA. Toe plates and this digital level are tits for a quick home alignment. The only thing ot mind is badly un-level surfaces and total toe, as in the wheels can read a good toe measurement, but they can both be turned to the side a bit. That can be overcome with some dicking around (the string method does help there). The pull you have could well be the road, if you have a long empty one, drive on the wrong side (carefully) and see if it runs straight or pulls the other way. I always ran mine flat and straight I did so much interstate driving, they don't crown 4 lanes, or not much if they do.
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Old 04-03-2011, 11:12 PM   #12
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Originally Posted by iwannadrive View Post
Also, just wondering, I remember back awhile ago a thread where you made some ghetto 'coilovers' with just some 2" PVC pipe acting as a bushing to keep a 2.5" spring centered. I believe you had something like 250# springs on DeCarbons - How did that handle for a street setup? I know that 250# is pretty soft, but I'll be getting some decarbons for free next weekend, and that's probably about all they can handle. Would the body roll be very excessive with ~250# springs and the equivalent of about a 26.5mm front bar?
It will roll, but that's OK. 250lb is nice on Bilstein HDs or orange DeCarbons. Just don't go really low. About 1-1.5" lower than stock is all I did, and the front felt great. Rear was stock springs, stock bar, stiff shocks (volvo r-sport). It handled really nice for a daily driver, had great grip in the rain, and felt good on high speed turns (highway) and transitions. But really quick changes in direction will still produce body roll, and perhaps some understeer. I just autocrossed my DD on 205/60 all seasons, 28mm front bar, -1.5 camber, 350lb front springs, Koni yellow struts. It was pretty good most of the time, but a hard/quick turn-in during a slalom would break traction at the front. Had to be really smooth with steering inputs and try to carry speed. It helps to have at least a degree negative camber, then the bar is doing something...maintaining the tire contact patch. Without camber, the big bar is not as useful.

If the steering wheel is off center, then you need to pull in one tie rod and extend the other out. So give it say half a turn in on one side and half a turn out on the other. Same total toe, but you've changed the center line so the steering wheel position when going straight should be different.

Once you have it set where you want it, you can easily measure the change made by X amount of turns. Then if you go autocross or run at a track, you can change the toe w/o measuring if you have a known setup already. Write everything down, it's MUCH easier when you need to refer to it later.
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Old 04-04-2011, 12:20 AM   #13
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Also, what I noticed is that the alignment as it was before I touched it tracked pretty straight, but the left tie-rod had only about 2 threads showing between the flats and the rod end, while the right had about 6 or so threads showing. Pretty sure the car hasn't ever been in an accident, but I guess I don't know for sure.
Pretty sure that the tie rods originally were equidistant/equal threads, so I'd guess your steering wheel was off the whole time and the rack was offcenter also. Was the rack or steering shaft joints ever replaced?
I think make the threads on the tie rods pretty much the same, which will center the rack, then reposition the steering wheel, and do a final toe set to the now centered wheel.
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Old 04-04-2011, 12:48 AM   #14
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It is effected by camber for sure, set the camber first. I never paid attention caster since it isn't adjustable on all my stock junk. I've alligned like towerymt said but I'm lazy and bought longacre racing toe plates (they were cheap) and use a digital level for camber. Haven't done the 240 yet but have done Rabbits and other old stuff, will hit the 240 this week soon as I get tires for it.

FYI, I've done the string method, and it can be very accurate, but it's allll in the setup, and it's a time consuming PITA. Toe plates and this digital level are tits for a quick home alignment. The only thing ot mind is badly un-level surfaces and total toe, as in the wheels can read a good toe measurement, but they can both be turned to the side a bit. That can be overcome with some dicking around (the string method does help there). The pull you have could well be the road, if you have a long empty one, drive on the wrong side (carefully) and see if it runs straight or pulls the other way. I always ran mine flat and straight I did so much interstate driving, they don't crown 4 lanes, or not much if they do.
It was on a few different roads, but I re-did it today and found that somehow I was off by nearly a half inch of toe-out on the right side. Haha. Not sure exactly how that happened, but my string setup was slightly janky and it was close to midnight when I finished up with it.

Anyways, I re-did it today using a slightly ghetto string method that I devised, and now it tracks pretty close to straight. I believe I also got it to where it has just a hair of toe-out, but really I can't know for sure. I didn't have anyone around to help me measure the distance between the front and the rear of the tires, so I don't really know for sure. I think the steering wheel is very slightly off though, by around 15 degrees. (because it ends up in different positions at both ends of steering range ("lock to lock"))

I'll re-do it when I have more time to get it perfect, though. I could really care less about my tires right now, so I don't really mind if my alignment is slightly off for a week or so.

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It will roll, but that's OK. 250lb is nice on Bilstein HDs or orange DeCarbons. Just don't go really low. About 1-1.5" lower than stock is all I did, and the front felt great. Rear was stock springs, stock bar, stiff shocks (volvo r-sport). It handled really nice for a daily driver, had great grip in the rain, and felt good on high speed turns (highway) and transitions. But really quick changes in direction will still produce body roll, and perhaps some understeer. I just autocrossed my DD on 205/60 all seasons, 28mm front bar, -1.5 camber, 350lb front springs, Koni yellow struts. It was pretty good most of the time, but a hard/quick turn-in during a slalom would break traction at the front. Had to be really smooth with steering inputs and try to carry speed. It helps to have at least a degree negative camber, then the bar is doing something...maintaining the tire contact patch. Without camber, the big bar is not as useful.

If the steering wheel is off center, then you need to pull in one tie rod and extend the other out. So give it say half a turn in on one side and half a turn out on the other. Same total toe, but you've changed the center line so the steering wheel position when going straight should be different.

Once you have it set where you want it, you can easily measure the change made by X amount of turns. Then if you go autocross or run at a track, you can change the toe w/o measuring if you have a known setup already. Write everything down, it's MUCH easier when you need to refer to it later.
That's awesome. I think I'll go set up a saved search for 8" or 10" 250# springs then. Would you think cut 245 rear springs might shift the handling balance close to neutral? I think I might do that, and then tune with the rear bar. (I have 16, 19, and a 21mm rear bars)

Just out of curiousity, how does a 240 with nearly stock, soft suspension in the rear, and stiff stuff up front? Is it horribly understeer-prone? I've read that it's best to basically focus on the front with suspension tuning, because the rear basically just follows the front and doesn't do much work. Is that somewhat correct?

Also, I should be able to dial in a few degrees of camber and a little more caster when I put on my ghetto-widened control arms. How important is it really, to have poly in the rear of the control arms? (I believe I remember you saying that it's most important to use poly in the rear of the control arms, and the trailing arms... Correct?) Might just new rubber CAB's do alright? I'd really love to get poly stuff, and remove a bunch of the slop in the front suspension, but it's just so expensive. I think I remember being quoted $80 for a pair of just the rear superpro CAB's. Any alternatives here, or do you think good new rubber bushings might suit me fine (it is a daily driver, but I like to beat on it a little bit, and it will see a few autocrosses per summer.)

Thanks for the info on the off-center toe, by the way. As soon as I start thinking about this stuff too hard, it confuses the hell out of me. Haha.
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Old 08-24-2021, 01:37 PM   #15
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10-year bump. Curious if Towery has any updated input or if the wisdom from the old days is still where it's at.
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Old 08-24-2021, 05:17 PM   #16
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He’ll tell you to crush your race car.

Get caster as high as possible. Otherwise it’s mostly the same.
I’ll get mine running and do a skid pad test with tire temps.
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Old 08-27-2021, 08:27 AM   #17
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How important is it really, to have poly in the rear of the control arms? (I believe I remember you saying that it's most important to use poly in the rear of the control arms, and the trailing arms... Correct?) Might just new rubber CAB's do alright? I'd really love to get poly stuff, and remove a bunch of the slop in the front suspension, but it's just so expensive. I think I remember being quoted $80 for a pair of just the rear superpro CAB's. Any alternatives here, or do you think good new rubber bushings might suit me fine (it is a daily driver, but I like to beat on it a little bit, and it will see a few autocrosses per summer.)
propav8r - While vintage racing with the VSCCA I've found that poly bushings at the rear of the rear lower control arms and rubber bushing in the the rest of the rear arms and no rear sway bar doesn't allow the rear suspension enough flexibility. The poly will not allow both tires (radials) to be firmly planted during sharp cornering and causes snap oversteer at the limit. If you don't catch it quickly enough when it happens most Volvos will spin. Other more gentle corners on the tracks we run with poly rear bushings these cars have the typical Volvo predictable understeer. A change back to rubber rear bushings ends the issue.

The car is not a 240, but is a 2400lb '67 1800S setup with a large front IPD sway bar 450lb front and 200lb rear springs (it's also street driven) has -1.5 camber -.5 caster and has Koni adjustable shocks.

Other members of the HVRRS - Historic Volvo Racing & Rally Society that run 122/1800 and 142 series cars (similar to a 240) report the same issue with poly bushings. In most cases adding a rear sway bar to these cars causes the same problem, and allows the inside rear wheel to lift in sharp corners.

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Old 08-27-2021, 02:16 PM   #18
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propav8r - While vintage racing with the VSCCA I've found that poly bushings at the rear of the rear lower control arms and rubber bushing in the the rest of the rear arms and no rear sway bar doesn't allow the rear suspension enough flexibility. The poly will not allow both tires (radials) to be firmly planted during sharp cornering and causes snap oversteer at the limit. If you don't catch it quickly enough when it happens most Volvos will spin. Other more gentle corners on the tracks we run with poly rear bushings these cars have the typical Volvo predictable understeer. A change back to rubber rear bushings ends the issue.

The car is not a 240, but is a 2400lb '67 1800S setup with a large front IPD sway bar 450lb front and 200lb rear springs (it's also street driven) has -1.5 camber -.5 caster and has Koni adjustable shocks.

Other members of the HVRRS - Historic Volvo Racing & Rally Society that run 122/1800 and 142 series cars (similar to a 240) report the same issue with poly bushings. In most cases adding a rear sway bar to these cars causes the same problem, and allows the inside rear wheel to lift in sharp corners.

yep, poly is trash for the back of these cars and ruins everything.
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Old 08-27-2021, 02:41 PM   #19
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yep, poly is trash for the back of these cars and ruins everything.
When I ditched all the poly out back and did the spherical TABs and hybrid torque rods I could feel the difference pulling out of the driveway!
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Old 08-27-2021, 03:48 PM   #20
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The car is not a 240, but is a 2400lb '67 1800S setup with a large front IPD sway bar 450lb front and 200lb rear springs (it's also street driven) has -1.5 camber -.5 caster and has Koni adjustable shocks.
That’s a very, very soft front spring. We are running either a 1” or 1 1/8” IPD front bar, 925lb front springs with 200lb rears and no rear bar on our 2300lb 142. Granted, we’re using Hankook RS4 tires that are sticky sticky in mostly endurance racing scenarios with -3 degrees of front camber, but 450lb springs on a double wishbone setup is more of a performance street spring rate. If it’s balanced well on the less grippy tires and reduced camber, it’s all good, that just stood out to me. I do think the factory rate is somewhere between 300-350lbs or so?

Ps. You can use poly in the pan hard rod, but otherwise, yes, all rubber and/or heim joints back there is best.

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Old 08-27-2021, 04:03 PM   #21
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I agree. IF the spring is at the halfway point between bushing and ball joint (and a 144 is close, haven't measured an 1800), it has a motion ratio of 0.5, so the pressure at the wheel is half that of the spring, and the distance the ball joint moves is twice that of the spring. 500lb/2 inch, which gives a wheel rate of 250 lb/inch.
For non-easy numbers, we square the motion ratio. (0.5 x 0.5 = 0.25 mr^2)
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Old 08-27-2021, 04:58 PM   #22
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He’ll tell you to crush your race car.
Ouch.
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Old 08-27-2021, 05:52 PM   #23
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I said that because his old race 244 is going away.
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Old 08-28-2021, 07:49 AM   #24
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Originally Posted by klr142 View Post
That’s a very, very soft front spring. We are running either a 1” or 1 1/8” IPD front bar, 925lb front springs with 200lb rears and no rear bar on our 2300lb 142. Granted, we’re using Hankook RS4 tires that are sticky sticky in mostly endurance racing scenarios with -3 degrees of front camber, but 450lb springs on a double wishbone setup is more of a performance street spring rate. If it’s balanced well on the less grippy tires and reduced camber, it’s all good, that just stood out to me. I do think the factory rate is somewhere between 300-350lbs or so?
klr142 As I have mentioned to you a couple of times before the setup is a compromise because of the rules and in addition to being raced it is also driven on the road about 5K miles a year, and the reason for the softer spring rates. Yes, the original front spring rate is only about 300lbs.

We race with the VSCCA and according to the rules all post 1959 cars have to remain as "could be bought off of the showroom floor." The Club is one of the last holdouts in the vintage racing scene that continues to do it the old-fashioned way, and a number of the cars are still driven to the event. Only original tire sizes are allowed and only treaded racing tires are legal.

The rules state that all post 1959 cars have to remain as "could be bought off of the showroom floor" which means "showroom stock." Despite this the setup in the car is working well and after you learn how to race with this way it works out OK.

Despite having a trailer it has been driven to and from competition meets since starting racing in 2018. In pre-Covid times it has covered about 1k miles a year on the the track or in hillclimbs.

Last edited by vintagewrench; 08-28-2021 at 07:55 AM..
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Old 08-30-2021, 02:04 AM   #25
klr142
Turbo, what?
 
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Ah yes. Good info to share and I believe it does just fine! My street/play 240 is very softly sprung as well but does fine enough on the track in short bursts. That car is still stock upper strut mounts and lower control arms so it only has about a degree of camber up front. It could definitely benefit from more, but it does ok for what or is.
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