Had my 2017 build year 1600cc VS out for probably the final time this year, cruising NW Indiana back roads for 3 hours or so. Was the longest cruise since I picked it up in Sep. At one point I was driving 105 mph, which is far faster than I thought the car was capable. The car felt stable and well grounded. Is there a speed at which these cars are known to become aerodynamically unstable? Can anything be done to improve safety at high speed?
Thanks.
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Sounds like you were having a great time! Is there enough caster in the front end? The rest of the front end is up to spec? Tires are good?
IMHO Safety and high speed (your 105mph ) fall into two opposing realms. Excessive speeds in a pan based FG car is not a good thing as the initial downward force over the front can change in an instant to getting too much air under the pan …. Just my .02
Hi Ron,
Sounds like your VS is new to you. Are you sure your speedo is in MPH, and not KPH (kilometers/hour)? 105 kph is 66 mph.
Under ideal conditions of slight tail wind and downhill straight road, 105 mph may be possible with a 1600 engine, but, if done regularly, it will shorten the life of your engine, which likely produces about 40 HP.
ALB posted:Sounds like you were having a great time! Is there enough caster in the front end? The rest of the front end is up to spec? Tires are good?
I was! Thanks for your input. The tires are in good shape and properly inflated. What would I judge the front end spec against?
Alan Merklin posted:IMHO Safety and high speed (your 105mph ) fall into two opposing realms. Excessive speeds in a pan based FG car is not a good thing as the initial downward force over the front can change in an instant to getting too much air under the pan …. Just my .02
Is there consensus on when speed becomes excessive? Thanks for your help.
The car will start to feel "floaty" in the front when you are close.
Jim Kelly posted:Hi Ron,
Sounds like your VS is new to you. Are you sure your speedo is in MPH, and not KPH (kilometers/hour)? 105 kph is 66 mph.
Under ideal conditions of slight tail wind and downhill straight road, 105 mph may be possible with a 1600 engine, but, if done regularly, it will shorten the life of your engine, which likely produces about 40 HP.
Yes, Jim, it is new to me. I'm sure it's in KPH. I actually didn't realize I was traveling that fast as I thought the mph equivalent of 170 kph was about 90 mph. Not prepared to replace the engine...yet! Thanks for your help.
Stan Galat posted:The car will start to feel "floaty" in the front when you are close.
Thank you, Stan.
170kph, well 90=55mph and 80 is about 50mph, so 105 mph is about right....
I thought someone was going to say it was going to fly away.
As to "Is there consensus on when speed becomes excessive? "
Pretty much faster than walking for some people.
IaM-Ray posted:170kph, well 90=55mph and 80 is about 50mph, so 105 mph is about right....
I thought someone was going to say it was going to fly away.
As to "Is there consensus on when speed becomes excessive? "
Pretty much faster than walking for some people.
Understood and thank you.
Ron P posted:
...Is there a speed at which these cars are known to become aerodynamically unstable?...
Keep in mind your suspension was designed in the 1930's. There are things you can do to help a little - better shocks and sway bars - but significant improvements are expensive. An IRS rear is a huge improvement, but converting can be complicated.
On a swing axle, pan-based car, I think the suspension will get you before aerodynamics, but it's how it will get you that's the problem.
My VS is very sensitive to the quality of the surface. On smooth asphalt (like a freeway), it seems stuck pretty well. I've had it to 90 briefly on the freeway (very briefly) and still had control.
But rough, macadam roads are different. The front is very light and starts skittering around at speed on a bad surface. I don't think the body's lift is doing that - there's just not enough weight pushing the tires onto the road, and the geometry's too crude to help much.
The problem is what happens if a good surface turns suddenly bad (pot holes, ruts, gravel, debris, etc.) You could be in over your head before you know it. And, with swing axles, the real danger is how quickly things can change on you once you exceed the limits.
I'm very wary about braking hard with this car. The front tends to slide earlier than on modern cars and once you lose grip at either end in a rear-engined, swing axle car, you cease being a driver and are more a spectator.
I'm reminded of the old pilot's saying:
There are old pilots and there are bold pilots, but there are no old, bold pilots.
Be careful out there.
Sacto Mitch posted:
Ron P posted:
...Is there a speed at which these cars are known to become aerodynamically unstable?...
Keep in mind your suspension was designed in the 1930's. There are things you can do to help a little - better shocks and sway bars - but significant improvements are expensive. An IRS rear is a huge improvement, but converting can be complicated.
On a swing axle, pan-based car, I think the suspension will get you before aerodynamics, but it's how it will get you that's the problem.
My VS is very sensitive to the quality of the surface. On smooth asphalt (like a freeway), it seems stuck pretty well. I've had it to 90 briefly on the freeway (very briefly) and still had control.
But rough, macadam roads are different. The front is very light and starts skittering around at speed on a bad surface. I don't think the body's lift is doing that - there's just not enough weight pushing the tires onto the road, and the geometry's too crude to help much.
The problem is what happens if a good surface turns suddenly bad (pot holes, ruts, gravel, debris, etc.) You could be in over your head before you know it. And, with swing axles, the real danger is how quickly things can change on you once you exceed the limits.
I'm very wary about braking hard with this car. The front tends to slide earlier than on modern cars and once you lose grip at either end in a rear-engined, swing axle car, you cease being a driver and are more a spectator.
I'm reminded of the old pilot's saying:
There are old pilots and there are bold pilots, but there are no old, bold pilots.Be careful out there.
I always think of 95 year old Chuck Yeager when I read that adage. Still, I admit it's mostly true. Thanks for your valuable advice.
"You could be in over your head before you know it. "
I read this and I heard over the top in my mind "
Mitch is right, It is an old car that needs respect, more so with swing axles. IRS and front beams are better but of course a full 911 front and rear is the max for control.
In any of them, sudden stops will not be forgiving.
If you pegged your KPH speedo, you’d only be doing about 80MPH.
https://www.google.com/search?...i10j0i10.7eYhzEeYyPE
In perspective: "Never drive faster than your Angles can fly"
As I've said before, an original A-bodied 356 was in essence (and in actuality, in many ways) a sporty VW beetle. Now that we've made Herr Doktor a god in the automotive pantheon, we assume that everything he did was driven by a desire to build the best possible car (Excellence was Expected, and all that rot). It was not.
Porsche was trying to build a viable sportscar company in the ashes of a war-shattered country, which was no small undertaking. Auto Union and Mercedes Benz had a pretty huge head start, and Alfa Romeo and Ferrari were picking themselves up and dusting off after the war themselves.
In order to be viable, they had to use materials at hand... which included (among other things) the swing-axle and front suspension he'd designed for the people's car prior to the war (in the 1930s). Herr Doktor (and his son) polished those turds until they worked well enough to win some races (mostly by not breaking). They built a viable and profitable car company on the reputation.
In hindsight, it's taken as an article of faith that the Porsche engineers knew exactly what they were doing with his rear-engined sportscar, but the original 356 and early 911 killed a lot of people before they finally abandoned the ridiculous swing-axle and beam, then lengthened the wheelbase (of the 911) in 1969. Coincidentally, this was the same year VW finally changed the rear suspension to IRS. It only took Porsche about 15 years and 2 generations of cars to make a rear-engined sportscar something less of a death-trap.
Beck is nearing production of a mid-engined replica with IRS and a modern front suspension. Every Vancouver built Intermeccanica has been IRS (even the pan-based cars), and since the mid-80s has been built on a frame that relocates the engine 2" forward. My huge regret on my car is not getting the 911 front suspension (because I didn't know it was available), but these have been around for 15+ years as well. If you've ever driven a replica with a real suspension, you know what you are missing.
I can take my car up to 120 or so, without feeling out of control, but going that fast feels like I'm Chuck Yeager trying to break the sound barrier. Going that fast in a modern car really isn't anything special, and going that fast in a modern sportscar is a total non-event.
Cars have come a long way in 60 years.
Well that sums it up ! But for those that still think Ferdinand was Rah
Stan, you nailed it. Your description matches my own opinion of how things were and why. Why it took so long to get away from that archaic suspension, we'll never know.
I would LOVE to build a coupe with Carey's new layout. It is the way forward. I can only dream of a Spyder so equipped, it doesn't exist.
But having said that, I can do a buck-twenty as well, and feel perfectly safe doing so. But I tend to not stay there, as reality of what happens during a sudden stop from that speed could do.
I think I've got my beam/swingaxle combo just about dialed-in as much as anyone could. Honestly the only improvement I could make at this point is tires. We had a great time running with you in North Carolina, Stan. It was an excellent experience of roads, scenery, and friends.
So, @RonP, in practical terms just take a look at the side profile of your car and what do you see? A wing - and a wing creates lift. The car is already light sitting still and becomes more so as the forward speed increases.
Couple that with a swing-arm rear suspension (which you have) and a couple of things happen that you must watch out for:
1. The car can get light and "floaty" at higher speeds and may tend to wander around in the lane and/or follow bumps and uneven-ness in the pavement (you may have noticed this in your jaunt). THAT can become disconcerting for some drivers and can happen at speeds as low as 35-40mph. The best way to improve that is to add caster shims to the bottom front torsion bar to improve front suspension geometry, and maybe increase the front toe-in a tiny bit (those shims are available from CB Performance and CIP1, among others). Properly set up, a VW beam front end can be stable up to 90 or so. It improves handling in the 35 - 80 range, too. Do a search on here for caster shims and read up on them. They're cheap and most of us use them and many of us keep up with interstate traffic which is usually running 75 - 80mph here in New England.
2. With a swing-arm rear suspension, as the car lifts and gets lighter, the rear wheels travel up and down in an arc, not straight, so if you were to jack the rear wheels off of the ground they tuck in under the car. Secondly, as you take faster and faster corners, centrifugal force pushes the inside corner side of the car up. When that happens, the wheels tuck under the body and, because of the centrifugal force, the wheel tucking and movement of the car, the outside corner rear wheel can actually ride up on the sidewall of the tire (not good) and in extreme cases can push the tire sealing bead off of the rim causing an instantaneous blow-out. Now, imagine that happening when you hit an abrupt turn at a speed which would be fine in a Toyota Camry but too fast for a swing-arm Speedster with no suspension mods. Rapidly (like in the blink of an eye), the car sways up, the wheels tuck under and lose traction, the rear end almost instantly goes into oversteer and comes around to meet the front end. If you were lucky the wheel tuck wasn't bad enough to cause the car to roll over..... A few years back, we had a member of this site do exactly that and rolled his car and died - and he was not a reckless driver.
So, if you want to continue with "Spirited Driving" with this car, please take it to a decent alignment shop and have them check/increase the front end caster to 5º - 7º to make it more stable. The rest of the alignment specs are the same as a 1970 VW sedan. You should also add a Camber Compensator to the rear suspension to manage the wheel tuck and make the car a lot safer. We've been mentioning this to some of the newbies on here and it's not a "nice-to-have" option - It's a Must-have (in my opinion) for all swing-arm cars. Yes, the Camber Compensator was developed for race applications, but it does wonders for street cars, too.
Good luck with your new toy, but remember that it uses 1950 technology with a fiberglass egg-shell body, so there is VERY little protection in a crash. We just want to see you safe while you're having fun.
The Speedstah Guy from Massachusetts.
Took my speedster up to 105 in the NV desert once. It has a new front beam, 4 wheel discs, sway bar, and camber compensator. Felt OK but a definitely got light in the front end. I think 75 is about it for me. Drove my Alfa Guila Q4 on the same back road last week to 155 without terror other than tractors and farm animals lurking unseen.
Rich Drewek posted:
If you pegged your KPH speedo, you’d only be doing about 80MPH.
https://www.google.com/search?...i10j0i10.7eYhzEeYyPE
Mine might be different from what's typically seen.
Gordon Nichols posted:So, @RonP, in practical terms just take a look at the side profile of your car and what do you see? A wing - and a wing creates lift. The car is already light sitting still and becomes more so as the forward speed increases.
Couple that with a swing-arm rear suspension (which you have) and a couple of things happen that you must watch out for:
1. The car can get light and "floaty" at higher speeds and may tend to wander around in the lane and/or follow bumps and uneven-ness in the pavement (you may have noticed this in your jaunt). THAT can become disconcerting for some drivers and can happen at speeds as low as 35-40mph. The best way to improve that is to add caster shims to the bottom front torsion bar to improve front suspension geometry, and maybe increase the front toe-in a tiny bit (those shims are available from CB Performance and CIP1, among others). Properly set up, a VW beam front end can be stable up to 90 or so. It improves handling in the 35 - 80 range, too. Do a search on here for caster shims and read up on them. They're cheap and most of us use them and many of us keep up with interstate traffic which is usually running 75 - 80mph here in New England.
2. With a swing-arm rear suspension, as the car lifts and gets lighter, the rear wheels travel up and down in an arc, not straight, so if you were to jack the rear wheels off of the ground they tuck in under the car. Secondly, as you take faster and faster corners, centrifugal force pushes the inside corner side of the car up. When that happens, the wheels tuck under the body and, because of the centrifugal force, the wheel tucking and movement of the car, the outside corner rear wheel can actually ride up on the sidewall of the tire (not good) and in extreme cases can push the tire sealing bead off of the rim causing an instantaneous blow-out. Now, imagine that happening when you hit an abrupt turn at a speed which would be fine in a Toyota Camry but too fast for a swing-arm Speedster with no suspension mods. Rapidly (like in the blink of an eye), the car sways up, the wheels tuck under and lose traction, the rear end almost instantly goes into oversteer and comes around to meet the front end. If you were lucky the wheel tuck wasn't bad enough to cause the car to roll over..... A few years back, we had a member of this site do exactly that and rolled his car and died - and he was not a reckless driver.
So, if you want to continue with "Spirited Driving" with this car, please take it to a decent alignment shop and have them check/increase the front end caster to 5º - 7º to make it more stable. The rest of the alignment specs are the same as a 1970 VW sedan. You should also add a Camber Compensator to the rear suspension to manage the wheel tuck and make the car a lot safer. We've been mentioning this to some of the newbies on here and it's not a "nice-to-have" option - It's a Must-have (in my opinion) for all swing-arm cars. Yes, the Camber Compensator was developed for race applications, but it does wonders for street cars, too.
Good luck with your new toy, but remember that it uses 1950 technology with a fiberglass egg-shell body, so there is VERY little protection in a crash. We just want to see you safe while you're having fun.
The Speedstah Guy from Massachusetts.
Thanks, Gordon, for taking the time to share this valuable advice. It's really appreciated.
Ron, another note about speedometers. The Chinese recreations (of the original VDO units) that VS used vary widely in accuracy. Some are pretty close, but the one in my car, for example, is optimistic by about 10 per cent - maybe more over 70 mph.
It's a good idea to check yours against a GPS before putting any faith in it.
My tach is pretty good, though, so I've just learned to figure out speed from that.
And if you’re reading that KM/H speedo at face value, then 105 KM/His about 63 mph. I have a kilometer speedo, too, and you learn to multiply what it says by 6 to get mph - that gets you in the ballpark, anyway.
Interstate speeds around here have me cruising at 120 - 140 KM/H to keep up.
Now it all makes sense; I knew there was no way a 1600cc was pushing 105mph, not without a few extra gears and a long straight road or a dry salt lake bed!
That km/h conversion is a useful tool though. I watch my tach far more than my speed; basically I just stay in the right land and enjoy the drive when everyone flys be me in a rush to get to the next red light or stop sign. The best part is when I roll by them when I get the green...I always feel like I’m making my brake pads and shoes last longer too!
My car’s gearing was such that when 4th gear I could take the tach reading and double it to get my speed. I checked it against my GPS and it was pretty darned accurate. Your mileage may vary, of course.
Don't drive too fast if you're not on a race track.
Yes, Dad.......... 
edsnova posted:Don't drive too fast if you're not on a race track.
Define “too fast”.
30 min? Ain’t nobody got time for that, Uncle Ed.
Son, don't be a pin head.
No danger of thet, Eddie. I can’t be a pinhead with my double-exta-jumbo noggin’.
Meathead, certainly. Fathead, likely. Pinhead— just not happening.
@EDSNOVA: Great film! How did you ever find that?
Ed, I watched the whole thing, spellbound.
I think that was the golden age of driver education films. The subtle use of foreshadowing was groundbreaking. I'm astounded it didn't receive more critical acclaim.
Stan, you don't know what you're missing.
Watching those old cars careen around reminds me of riding in the 'family sedan' of the fifties (unfortunately, I'm that old - my dad had a '52 Buick).
Those cars might explain why Porsche may have been a little slow to upgrade their suspensions. Compared to those tanks (and even some 'sports cars' of the mid-fifties), the 356 handled pretty well. The car (the whole car) actually moved when you turned the wheel, stayed pretty flat, and got through a corner way faster than anything Detroit was making at the time.
In the fatherland, even the Ultimate Driving Machine of the mid-fifties looked like this:
I remember that my dad was scared to drive the Buick over about 60 mph. Manual drum brakes and manual steering (with a wheel the size of our breakfast table to sort of get a handle on it). You felt like you were cruising down the road in a studio apartment.
Comfy, but changing direction took some planning.
Bias ply tires also played a part in some questionable lane changes.
There wasn’t a car in that video that I wouldn’t want to have. But the way they handled looked like a nightmare!
For years I thought I’d be safer in a mid-50’s sedan. Then I watched the video in the link below:
I hope the link works...I’m still trying to figure out how to add video attachments here.
TheMayoMachine posted:Now it all makes sense; I knew there was no way a 1600cc was pushing 105mph, not without a few extra gears and a long straight road or a dry salt lake bed!
That km/h conversion is a useful tool though. I watch my tach far more than my speed; basically I just stay in the right land and enjoy the drive when everyone flys be me in a rush to get to the next red light or stop sign. The best part is when I roll by them when I get the green...I always feel like I’m making my brake pads and shoes last longer too!
Surely almost everyone can perceive the difference between 60 and 100 mph. My speedo read 170, not 105. 170 kph converted to mph is about 105. Next time I'll be sure to grab a video!
