I just had an enthusiast lose interest in my 2023 built VMC Speedster that was up for sale because it does not have independent real suspension. Is IRS such an important thing? This is the second Speedster I have owned over the years; I am not seeing it as such an important option - the cars I have had performed well without it. Thoughts?
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There are benefits to IRS for sure, but with the right add on's you can still have fun in a swing axle car. You need a camber compensator, good adjustable shocks, heavy sway bars, sticky tries and filled with the proper trie pressure and some limiting straps. It's going to be a learning experience adjusting to how to drive the car, but can be fun as well. I had a 68 bug in High School that was all EMPI'ed out with the stuff mentioned above. It would keep up with most of the sports cars on twisty roads back then. Hope that helps.
I assume since the buyer was buying "almost" new, he wanted the best and latest. Not knowing what you were asking, that may have been the deciding factor since new ones are constantly comng to auction.
@Desert Canuck -- I know you're frustrated eBay didn't work out, and now it seems like somebody is picking the car apart over something that doesn't matter to you. Don't let it get to you. There's a buyer out there who (like you) doesn't care if the car has IRS or not. The original Speedster did not.
That said, there is a difference. Whether you or the prospective buyer drive aggressively enough to notice that difference is something I can't answer. I've had both -- and I would have a hard time going back to a swing axle, but that's just me.
Thanks for your thoughts Stan. I guess without driving a Speedster with IRS, or actually driving my car aggressively, I could not comment on the difference myself. It now makes me think that it was a VMC option I should have considered.
I had an early 1st gen Beck Speedster with swing axle and only had it try to come around on me once (on The Rattler in NC during a Tour de Smo') in ~56k miles. Leon Chupp was behind me and commented on how far out of shape I got on a narrow, decreasing radius turn. I'd prefer IRS, but wouldn't let that be the deciding factor.
https://bringatrailer.com/list...rsche-356-replica-5/
My VMC Speedster which I recently sold is a similar spec to yours. It did not have IRS. I live in Minnesota, so there is not a ton of canyon carving or anything of that nature to be done. The stock handling was fine but left a little to be desired. After adding Koni red shocks, a stock VW front swaybar, and a camber compensator the handling definitely improved. It was more than enough for me, and unless I was going to track the car or had some serious back roads to carve, I don’t feel IRS would be an appreciable benefit. As mentioned above, real speedsters weren’t IRS. Some people will only want it because it is an available upgrade and that in and of itself adds value.
Good luck with the sale. I let mine go for a fairly low price compared to what they had been going for. I ordered in fall of 2020, so I only paid about 44k for mine. I didn’t lose money on it, so although it would have been nice to get about 60k for it, in the grand scheme of things that amount of money is fairly insignificant.
All great input - thanks to all. In Arizona, I have the benefit of two seasons for my car - one is in the cooler mountains away from the summer heat of Scottsdale; and then the winter is Scottsdale which is wonderful for driving the car. I spent time in Minnesota and points north, so I understand how drive time in snowbelt climates is so limited. I have seen the difficulty I had with my listing to be a sign from the "Speedster Gods" lol; so I am not actively working to sell my car right now....maybe in the late Spring next year. My health is better - so my challenge right now is for finding more space for cars - there are other people with more serious challenges in their lives, so I will not complain about that.
I’ve had 3 spyders with swing axle and have never had one sideways. Obviously these cars are better balanced with mid engine setup. I had an intermeccanica Conv D with IRS and a very heavy 2.0 L watercooled straight 4 hanging out the back. If I looked at that car sideways it would go sideways. Personally I’d probably want IRS in a speedster. Trying to get as much rubber in the back would also be helpful.
2332, IRS, 185-15s, HD sway bars front and back. Seems to work. The ass end has hung out a few times, but so far no 180 plus adventures.
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Technical arguments aside, 'independent real suspension' may be the typo of the day. Possibly of the decade.
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My 2013 VS, in which I have now logged 50,000 miles, is swing axle, and I have driven a few IRS cars.
IRS is better.
Better in an engineering sense and in an all-out performance sense. If you're a logical kind of guy, IRS is just plain better. But if you're considering one of these cars, even for just a minute, you're probably given to doing things that are not altogether logical.
I will admit that the first time I discovered the limitations of this swing axle arrangement was one of my life's more chastening moments. If someone had had a Go-Pro rolling and pointed at me at the time, I might have been immortalized on one of those viral YouTube short clips that is always making the rounds. Briefly, I was following a newer Lotus through a tight little S-shaped entrance to a local Cars and Coffee and I figured if he was making it through OK at this speed that I could do the same. I'll spare you the boring details, but the bottom line was that I couldn't.
But that was a learning experience. I've never since committed the same error, and my wife and insurance agent are both grateful. The point is all cars (and all drivers) have their cornering limits and part of this pursuit of ours is learning just where those limits are and respecting them. I have since learned how to get the car through a corner a lot quicker than I used to be able to and getting there has been half the fun.
With or without IRS, this car does not corner like a Ferrari. It doesn't accelerate like a Ferrari. But if you learn what it does do and how to make the most of that, you can have a great heap of fun with it. And while it may also require engine-out services from time to time like the Ferrari, these are not nearly as involved or expensive.
I had the EMPI camber compensator installed way back in the very beginning, but got rid of it early on to allow some mods to the transaxle mounts. I noticed no change in the handling. You will need a better compensator than that one for any real improvement. What I have learned to do is use the rear end's propensity to slide as another tool for getting through corners quicker — just like racers in the 1950s did. Watch these cars go at it at some of the Goodwood vintage races and you'll see what I mean.
It can be a lot of fun 'improving' these cars as much as possible to make them more usable, reliable, and practical driving machines. But it can also be a mistake to belittle a car that isn't tricked out with every last mod.
I think a buyer who balks at a well-prepared car simply because it doesn't have IRS has probably never driven either and is probably just looking for a way to monkey the price down. As Stan says, the stars will eventually align for you.
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@Sacto Mitch posted:.Technical arguments aside, 'independent real suspension' may be the typo of the day. Possibly of the decade.
Addressing the elephant in the room for any future "researchers" (although anybody using our thoughts for "research" needs to get a new understanding of the word) -- VW was notably reluctant to change the Beetle unless there was a good reason to do so. For years and years it was a part of their advertising, that their design was not given to the fickle winds of fashion and all that.
Think of all the hideously bad 1930s stuff they left on the cars: the ridiculous oiling system with pistons etc., the front torsion bar beam, the worm-gear steering. But the rear suspension they changed. It begs the question: why?
They would not have done it had there not been a compelling reason beyond, "it handles better". VW could not have cared less if their Beetles were carving canyons. But in 1969, they made a major change to the rear suspension, and they did it for one reason: snap oversteer.
You have to understand suspension design a little bit to understand why VW switched to IRS as a safety feature. A swing-axle moves in an arc, from negative camber with the suspension compressed to positive when it's fully extended. Think of camber is the position of the top of the wheel relative to the rear fender lip -- tucked further in, the camber is negative, out rubbing on the fender is positive. When the top of the wheel is tucked in more than the bottom on an angle, the tire "bites" harder in a corner -- that is, it has less of a tendency to slip and slide.
When the top of the tire is out more than the bottom, the car doesn't just slide -- it breaks loose all at once, in a pretty unpredictable way. There was a member here 10 or 15 years ago who rolled his car and died when he lost the rear in a snap-oversteer situation.
Camber compensators, limiting straps, etc. all work to keep wheel camber from going severely positive. Good ones make the car a lot safer, but they aren't the same thing as just fixing the design of the rear suspension. An IRS does that (fixes the problem at the source of it) -- it keeps the wheel from ever going positive, throughout the arc of suspension travel. It doesn't hold the wheel perfectly straight through the travel, because increasing negative camber as a suspension compresses is actually desirable, but it does keep the rear from going positive at the suspension is extended. This makes the car a lot more safe.
It should be noted that a beam doesn't do that in the front (increase negative camber as the suspension compresses), which is why unequal-length A-arms are so much better. But the camber on a beam doesn't get worse as the suspension unloads, so it's better than the swing-axle out back.
A swing axle would not be a deal-breaker to me, but there's a reason people pay extra for IRS, beyond just being able to say they have it.
Good analysis, Stan. Yes, the swing axle did/does have some disadvantages.
My favourite quote of all regarding a swing axle car, was found in a review of a Triumph Herald - the little sedan. After driving it on a test track (I believe it was that), and after an interesting cornering situation, the reviewer came up with this memorable line:
Hark! The Herald axles swing...
:-)
@Stan Galat, some of this was in response to Ralph Nader's book. Not only did VW change to IRS, but also added padded dash, crush cage to steering column, bigger bumpers and factory seat belts. VW was definitely looking at mitigating future lawsuits.
Interestingly, VW did not add some of these features to cars sold in South America, Mexico, Australia or other parts of the world. They probably weren't worried about litigation in these places.
Lots of things obviously will change the ways we go around corners. I have owned a Spyder without posi traction or an LSD or whatever you want to call it. I have owned 2 spyders with a LSD. Without an LSD in a car with swing axle the outer wheel goes from negative camber to flat and for a while will maintain traction . The negative camber of the inner wheel just gets worse and it starts to spin and smoke. Eventually the outer wheel will lose traction and the car will start to slide. But as it starts to slide the outer wheel starts to lose traction but the inner wheel gains some traction. It’s great fun and creates a lot of commotion. But as stated before if that outer wheel goes to positive camber lots of bad things can happen.
With a LSD the car can maintain traction with both tires at all times. It can go much faster than a car without a LSD to a point. But once you reach that limit both tires lose traction at the same time and it’s all over. You are looking at where you’ve been or maybe in a ditch.
So I kind of think the car without the LSD is safer. Not as fast but safer because you almost always have a tire with contact with the pavement.
Best situation for going fast is LSD with IRS. But without traction control, even with IRS and a LSD when you reach that limit you are gone.
In your humble opinions, if I were to pick a camber compensator at this point, who’s and which one is the superior one? Would I have to lighten( soften) the torsion bars as Porsche did when applying one to a car? Also, what is the size of a stock front sway bar? I don’t have one at all and would like to apply that also to my car. And also, unequal length A arms? Do I need? Esplain Lucy.
Tom C.
@LI-Rick posted:@Stan Galat, some of this was in response to Ralph Nader's book. Not only did VW change to IRS, but also added padded dash, crush cage to steering column, bigger bumpers and factory seat belts. VW was definitely looking at mitigating future lawsuits.
Interestingly, VW did not add some of these features to cars sold in South America, Mexico, Australia or other parts of the world. They probably weren't worried about litigation in these places.
I'm pretty sure we're saying the same thing though, Rick. VW hit the big safety stuff after "Unsafe at Any Speed", and left the rest. The swing axle was considered "big stuff".
Swing axles remained in Brazil, Mexico, and (probably) Australia because they were robust, with no exposed CVs with boots to tear, etc. Having been in all 3 places back in the day, longevity and ease of repair was likely the primary consideration. It's kind of like trucks -- there are a lot of us still trying to get over 4wd F150 Monster Trucks not having solid front axles (you can still get them in Ford Super Duty and Ram HD trucks, but if you're a GM man, so sorry).
IRS is fussier.
Kudos to me for starting a spirited discussion topic. My question has been answered; but please continue on. 
@Stan Galat, It was so good to see you say "could not have cared less". I think the vast majority of people say "could care less". If only they would think of the meaning of what they are saying.
@Gotno356 posted:In your humble opinions, if I were to pick a camber compensator at this point, who’s and which one is the superior one? Would I have to lighten( soften) the torsion bars as Porsche did when applying one to a car? Also, what is the size of a stock front sway bar? I don’t have one at all and would like to apply that also to my car. And also, unequal length A arms? Do I need? Esplain Lucy.
Tom C.
You can't go wrong with a Sway-Away Camber Compensator with no need to change the rear torsion bars. There are others out there, so check this out:
https://shoptalkforums.com/viewtopic.php?t=136278
A stock front VW anti-sway bar was 3/8" diameter and while it works, it is a bit soft. Most of the front anti-sway bars now sold as add-on bars are 3/4" which works well but may be a tad too robust - I have a 3/4" (19mm) on my Speedster and I like it. If you could find a 5/8" to fit your car, that would be ideal, IMO. Danny P made up his own 5/8" bar and loves the result.
The only bolt-in front suspension with unequal A-Arms I know of is the one from Mendeola - Pricey, but very well made. Not more than a handful of people on here have Mendeola front suspensions, and the newer evolution of Beck cars has something very similar. If you're not going to be tracking your car, then the expense of this is questionable.
https://www.coolrydes.com/t-1-front-suspension.html
Also, for more background on making a swing-arm car really handle, try reading this:
@Michael McKelvey posted:@Stan Galat, It was so good to see you say "could not have cared less". I think the vast majority of people say "could care less". If only they would think of the meaning of what they are saying.
Or proofread before you "submit".
Spelling, grammar, and usage all matter to some of us.
I am absolutely in agreement!
@Gotno356 posted:In your humble opinions, if I were to pick a camber compensator at this point, who’s and which one is the superior one?
Sway-Away
@Gotno356 posted:Would I have to lighten( soften) the torsion bars as Porsche did when applying one to a car?
I'd struggle to want to lighten the rear torsion bars. I'd think pretty hard about why I'd want to do it.
@Gotno356 posted:Also, what is the size of a stock front sway bar?
12 mm
@Gotno356 posted:And also, unequal length A arms? Do I need?
There's not an A-arm on anything besides a new Beck, or something with a Medeola or Red 9 beam replacement front suspension. The Beck design is great. You need a new car to get it. The aftermarket beam replacements have A-arms that are not all that different in length (upper and lower).
Short answer 'splainin': an IRS rear end is a step up from a swing-axle. An unequal-length A-arm front end is a step up from a VW beam. A Beck with an unequal length A-arm suspension front AND rear is fully modern in design and feel.
Is this a good thing, or even important to you? Only you can answer that. I like things that are "better" up to a point, but I just bought a motorcycle that shakes like a paint mixer, so what do I REALLY know?
I believe the OE VW front anti-sway bar was closer to 1/2"(maybe 12mm?). I have one in the garage I could measure.
Phil, the reason the inside rear tire gets light and spins on most Spyders under combined cornering and acceleration is that most are not equipped with anti-sway bars of any kind. This is why my Spyder corners flatter than most, and also why the inside rear does not spin. The combo of the front 5/8" bar(mid-way between the OE and the EMPI 3/4") and my limiting straps keep the rear end within a narrow range toward the good/excellent traction range.
There is a point that was not discussed by anyone above that needs to be addressed about swing-axle rear suspension. There is a thing called the "jacking effect". As you corner, the outside tire digs into and sticks to the pavement in opposition to your steering input. I won't get into details about how it all works, but the "roll center" on a swing axle is very high. The side force applied by cornering transfers all that force into an UPWARD movement of the outside wheel, hence jacking effect. Hence, Corvairs, Spitfires, and VW Beetles all being "Unsafe at Any Speed". This is also the reason that VW installed a factory camber compensator for a year or two before switching the design to IRS.
Limiting straps or camber compensators are installed to prevent this jacking effect which raises the outside of the car and causes rapidly diminishing traction. It is also why you NEVER install an anti-sway bar on the rear of a swing axle car. The rear anti-sway would simply raise the entire rear of the car whenever a cornering load was applied, causing positive camber on BOTH wheels, and instant loss of any traction.
Moving on to racing applications, early Formula Vee cars had two separate coilover shocks in the rear. Some travel limiting happened for a while with straps or rods. Then the Z-bar was invented. The Z-bar pushes one side down when the other goes up and vice-versa. So when you go around a corner and that inside wheel starts to lift(or the shock extends), the outside wheel is compressed by the Z-bar(or the shock compresses). If the shock compresses then we end up with NEGATIVE camber on the outside wheel where all the cornering load is being applied. The car sticks.
The problem with a Z-bar is that it adds spring rate. So you have to get lower rate spring(s) for each wheel and play a game of getting the combined spring rate of all springs used to be in the right range for good handling AND ride control. The 1968 Beetle had what is in effect a Z-bar from the factory.
Eventually we get to the "modern" Formula Vee which started in the mid to late 1970s. Yup, still using a 1961-1968 swing axle transmission. These use a single horizontal shock attached to rocker arms, then from each rocker arm to the outer area of the swing axle. With this arrangement a "droop rod" is installed parallel to the single shock/spring. The droop rod mechanically limits camber to wherever you set it. Most guys are in the range of 1.5 to 3.5 degrees of total negative camber, keeping the tires in excellent contact with the road. This results in Vees generating about 1.7 G of maximum cornering force(I have personally recorded 1.63+ in my car at Lime Rock Park). That is a pretty good amount of force being generated there on a 5.5" wide tire.
Here is an example. It is not my car, but mine is similar.
I have almost no idea what you were trying to explain, Danny. The rear suspensions on FV cars is very intriguing, but I'm almost completely lost about what is going on. It looks amazingly cool, but I don't get it.
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@Stan Galat posted:....Short answer 'splainin': an IRS rear end is a step up from a swing-axle. An unequal-length A-arm front end is a step up from a VW beam. A Beck with an unequal length A-arm suspension front AND rear is fully modern in design and feel.
Is this a good thing, or even important to you? Only you can answer that. I like things that are "better" up to a point, but I just bought a motorcycle that shakes like a paint mixer, so what do I REALLY know?...
Compared to most car dudes, I haven't owned many 'fun' cars over the years — a BMW 2002, a first gen Miata, and a 2009 MINI Cooper. None of those were modded from stock in any way, including the suspension, or even the wheels/tires.
The MINI is the sleeper of the bunch. It probably handles better than the Miata, and certainly better than the 2002, even though it's FWD. Those evil Bavarian engineers worked some magic there.
ALL of those cars handled 'better' than the Speedster — and the MINI by a huge amount, if by 'better' you mean predicability and absolute grip. The IRS Speedsters I've driven were closer to those other cars, but still not in the same league. (Maybe if you set one up for the track, you'd come closer, but I haven't driven such a car.)
But in a perverse kind of way, my barebones swing axle Speedster is the most fun to drive. You've got to work harder to get the most out of it. And there's always that voice in your head reminding you to stay away from the abyss at the limits of suspension travel. The fear of imminent disaster can add excitement to any activity.
I notice that I turn in less abruptly in the Speedster. I'm more aware of loading up the suspension gradually. And very careful about unweighting abruptly. I think that's at the heart of this car's appeal. It rewards being smoove maybe more than any other car I've driven. These are things you don't have to think about too much in the MINI. That car will save you from just about any miscalculation. So you drive it harder. More zoom, maybe, but strangely, less fun.
Of course, my opinions are probably shaped by the fact that I have no wish to drive now like I did 40 years ago. Folks are less forgiving of old farts driving like twenty-somethings than of twenty somethings driving like twenty somethings. We're expected to know better.
But there is a knack to driving quickly without looking or sounding like you are. No screeching tires or raucous pipes, but here you are right on the tail of the Mustang coming out of those twisty bits.
You sly devil, you.
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@DannyP posted:Here is an example. It is not my car, but mine is similar.
@DannyP is that what they call a zero roll rear suspension? It looks like the rear arms kind of mimic a DeDion tube with a Watts link, but not quite. I always thought that would work great on a Spider and be easier to fabricate than an IRS set-up.
That was part of why I was asking, @JMM (Michael). If that can pull 1.7g in a FV, I'm wondering why nobody has done something like that in a Spyder?
@Stan Galat posted:That was part of why I was asking, @JMM (Michael). If that can pull 1.7g in a FV, I'm wondering why nobody has done something like that in a Spyder?
I think Carey and company did and actual DeDion set-up for the spyder early on in the game, but this seems simpler to me. Plus we must face the fact that not many people will drive their spyders like you or Danny (or Chuck Beck) would. For Carey it probably wasn't worth it. If I were looking to workout my welding skills on my own build through...
The Beck Boys used to do a De Dion rear suspension way back in the Brazil-made watercooled inline 4 days. A De Dion rear suspension is basically a live-axle geometry-wise. It has coilovers(usually), trailing arms, and a long Panhard rod to keep the rear axle laterally in place. Thunder Ranch also used a similar setup on the 6 cylinder Spyders.
Yes, Michael, that is a zero-roll suspension. The zero-roll has zero resistance to roll, absolutely no anti-roll resistance.
@Stan Galat posted:That was part of why I was asking, @JMM (Michael). If that can pull 1.7g in a FV, I'm wondering why nobody has done something like that in a Spyder?
It has been done before. It would be very easy to implement on mine. You do need to figure out spring rate and lever ratios for the bellcranks/rocker arms.
When you jack up the rear of a zero-roll FV one tire or the other will touch the ground with a tiny push. If you remove a rear tire, the other side WILL touch the ground.
Hmmm... So if you want any resistance to roll you put it in the front, which would tend toward understeer - or actually countering the normal tendency to oversteer?
Yes and no.
What you are doing by using a huge front anti-roll bar in a FV is keeping the front flat and planted. By keeping the front flat the rear has to stay flat, the chassis doesn't twist.
BTW, the front bar is 3/4" usually, and is custom-made to take the place of one spring pack. The center grub screw is NOT used, making it an ant-roll bar only. Vees are so light(800 pounds empty) that only one spring pack is needed to keep the front end up.
Again, the rear suspension is LOCKED into a slightly negative camber state when under cornering loads due to the droop rod. So it sticks just fine as the car corners flat due to the front bar. Even with 60 hp the rear can slide under power, as it doesn't take much to go over the edge of traction when you're already on that edge. The Vees like to corner neutral to slight oversteer on exit, if you're doing it right.
You're correct that my Spyder might tend toward understeer, but in reality it is very neutral. It doesn't oversteer unless massively provoked and it doesn't understeer either. The car just goes the way you point it. It feels planted and neutral to me.
You'll have to excuse me if I don't respond for a couple days. I'm off to the track today.
Have fun and be safe.
