356 Handling Aids

[S.J.Szabo]

There is an interesting thread (wheel camber) on the Reg site, that begins with wheel camber, and segues to a good question by Mr.Benade...

"If you are lifting the inside rear tire, does that mean that your rear roll stiffness is increased by the regulator? Seems unlikely, but I thought that was the case when lifting an inside tire."

Mr.Benade has astutely put his finger on the weakness of the "camber regulator" in question. It is the case that the method of connection at the central pivot point does in fact, increase the rear roll couple, thus resulting in inside rear wheel lift.

The only connector that will allow a "virtual Z bar" of this type to function with a most accurate emulation, is a zero-force hinge that does not induce different forces at the ends of the cross bar.

While this device has its merits, it misses being a complete solution.

[JTR70]

Thanks for posting this up Stephen. I have been trying for years to wrap my mind around how that compensator spring actually works in there.

Here is the illustration from my Elfrink manual which I've combed over several times through the years. If its job is to help prevent excessive "positive" camber roll on the outside wheel in a turn I think limiter straps would be far more effective in softening that nasty trait on swing-axle suspension.

[badsix]

I've ever since the mid sixties wondered how that thing worked. as a kid in the sixties I had a 58 bug with a big 40 hp and a close ratio gear set. my girl friend lived out of town about 5 mi, that's 5 mi of twisty hard corner road. a good buddy of mine also lived out there and his folks had a 440 dodge charger. we would meet at the beginning of that 5 mi road several times, and the race was on. the vw was a rocket, I could be in his drive way and out of the car when he pulled in. then my future father in law gave me THE COMPESATOR after installing it I could smoke the charger by at least another full minute or more. I don't think it was the compensator that much, but the just knowing you had one made you think you could go faster.
Jay D.
PS I do have for my 356 just for that old feeling

[bbspdstr]

Also driving a 356 as a teen (then a 20+ y.o.) in the '60s, I was warned by more experienced drivers of "the dreaded oversteer" and many sorts of devices were tried to help avoid the wheel tuck of a "swing axle" rear suspension.

One thing taught early on was to be aware that the Factory helper spring is used as a "load leveler" with softer torsion bars. Added rear load (weight) is compensated, not the droop of the inside wheel on a curve.

"Cush" over performance and the ability to pile a couple of your frat buddies in the "back seats" without undue 'squat' of the 356.

A coupe of decades ago I bought and tried a Skirmants camber devise and abandoned it along with a ZF limited slip. I was used to the handling of an original archaic pre-WW2 German People's Car before I could afford the extras.

Except for the clumsy cage and added rear weight, I thought the H&H rear Z bar was best and if anyone wants that, $100 +shipping takes a new one off my hands. I took off an adapted early 911 front anti-roll bar from a C-2 that had been raced...again heavy and clunky...pay the shipping and it can be yours!

I got the best handling, almost neutral, in racing with an adjustable Weltmeister 19mm front bar and 28 or 30mm rear bars. Raised the trans as much as practical so the lowered car could have a neutral rear camber and same with the front with re-machined and reinforced front C-links, Konis on medium-hard, normal toe in the front and none in the rear with 6" light wheels and soft tires. Rotation was controlled by throttle-steer with great turn-in using a brake-bias and 911S rear calipers with slightly larger pistons. It was reminiscent of a full-bodied go-kart.

My Speedster had to weigh as much as a Coupe, so it was ballasted to 1705 pounds and corner-weighted with adjustable spring plates. The Coupes had a better Cd (less drag) by design and were hard to beat when set up and driven well.

That was in Vintage, not the overboard rules for SCCA EP from '76> with coil-overs, flares and 7" wheels with slicks plus 180hp engines and a 1600 pound weight minimum. All it takes is a LOT of money to make a 356 faster than anyone would expect but now they are becoming too valuable to worry about lap times over "numbers matching."

Basically, the 356s are now overall less driven and more worshiped. That is all well and good and I'm sure the good Doktor is pleased either way....but that's counter to how some of us 356 nuts began our addiction.

-Bruce

[S.J.Szabo]

Bars 'n Springs

[roy mawbey]

Super thread thanks SJ and Bruce for your inputs. I have the road and track copies of the Cd values achieved for the coupe and they were so good then. I have often wondered if the Speedster could ever be better then the drag factors of the coupe with its slippery shape. I suppose the power to weight factor of the speedster over the coupe evened out the higher drag values?

Roy

[bbspdstr]

I have the road and track copies of the Cd values achieved for the coupe and they were so good then. I have often wondered if the Speedster could ever be better then the drag factors of the coupe with its slippery shape. I suppose the power to weight factor of the speedster over the coupe evened out the higher drag values? Roy

Roy, in racing there were all sorts of aero aids tried on Speedsters, but in comparison with a Coupe they achieved approximately the Cd of a brick.

In "vintage" racing, the old Coupes, Speedsters...all 356s....had to weigh the same amount, so the aerodynamics made the difference (other than those who cheated with engines displacement, more frequent than we'd like to know)

One good thing about Vic Skirmants, who built my motors, was that he would NOT cheat when building a race motor. He was SCCA through and through and 'by the book.' Many a time, I'd catch and pass another 356 "in the twisties" only to have him blow by on a straight and we'd start that all over again...40-over 82.5mm/83.5mm vs 86mm or more makes a huge difference.

My best motor dyno'd at somewhere around 168HP, the Speedster weighed right at 1705 on each scale. It had the power-weight ratio of a 930 turbo without the aerodynamics or....damn! Torque.

I found some pictures from a Daytona event. The big thing was to cover the cockpit on the unoccupied side and rear and feed the frontal air up and over the helmeted head of the driver:









and then a few raced a Cabriolet with a lightened hardtop.




Really, the only advantage a Speedster or other open car would have is a lower center of gravity with a max'd track with just the right tires. Too wide and they would induce drag that cost horsepower on a long straight and too narrow, the side friction was insufficient for cornering.

[Phil Planck]

Bruce
Thanks for the photos and story. I always thought another advantage of open cars(Speedster) would be visibility. But maybe at speed you don't have that much time to be looking around.
Phil

[bbspdstr]

Bruce
Thanks for the photos and story. I always thought another advantage of open cars(Speedster) would be visibility. But maybe at speed you don't have that much time to be looking around.
Phil

Thanks, Phil...more story; I was used to being in open race cars only, as I raced my second Speedster in hillclimbs in the '60s. I realized as I grew older and got into 'vintage racing' that I was becoming more claustrophobic in all ways when confined...if there was no way to control any needed escape, so a Coupe was out. Safety gear didn't count, as I could put it on and knew I could release it if needed. I therefore got my last Speedster to race for the "openness" and not just to look around, but that was a plus.

I have always had a Coupe with a sunroof, A, B or C. I guess that sort of counts as an 'escape hatch' although with my B and C Coupes my symptoms weren't as severe, nor was there a problem in the tight confines of an aircraft cockpit in '69-'70. Then again, I was 'in control.' Hell, I need a pill now to fly commercial....'cause I'm not in control. End of that story.

As for the time to look around when racing a 356 of any model....long straights in 84255 let me check the gauges and turn dials to see the EGT and CHT of each cylinder, not just the one on all the time, #3, look in the mirrors to check for over-taking cars, wave to the crew on the pit wall, etc. Theoretically, on the gear charts and the fill-the-hole speedo, I was doing only 118 MPH at 7200 RPM. Compare that to racing a 930, where things were a whole lot busier at 140 or 150 or more....that took total attention and made a 356 feel ver-r-r-y slo-o-o-w.

Regards,
-Bruce

[roy mawbey]

I have to say you guys over the pond really know how to make a speedster look fantastic. The Cd might be like a 'brick' as you mentioned Bruce but wow, a very nice looking brick indeed.

Interesting points Bruce about racing coupe's and being caged up inside. Strange I had the same feeling when coming from motorcycles to cars. I always felt much more in control on a bike and never thought I
was vulnerable. Although of course found out the hard way that's not always the case

Roy

[S.J.Szabo]

[bbspdstr]

Mister Szabo, my writing in comparison with your writing makes me say that I wish I had English as a 'first language'!

You have also dug deeper into torsion bars than I ever have be able to find time to do, leading me to also say that as a 356 professional, I wish I could take the time to do as some 356 hobbyists such as you can find time to do! That makes me understand that I will only progress in my long career if I retire and let the hobbyist side of my split personality take over. (can you tell that I'm 'talking myself into' eventual retirement?)

As said in today's youthful slang; "it's all good." Perhaps if the Skipper gets wise to the 356 market's potential and deals more with the major 356-specific vendors (and we all know who they are), he would sell more product and more 356s would drive more like we remember.

When I fully restore a 356, I strive for the driving, the 'feel' and the sounds of what I remember from when 356s were new or only a few years old. There is no better sensory improvement to a 50+ year old sportscar like a 356 than a complete redo of the suspension. It's the same as the old 6v-12v or drum brake-disc brake arguments......each worked fine when new and will be impressive today when 'just like new.'

Wouldn't it be nice for our tired old bodies to be able to be rebuilt like our cars...and for the same money?

-Bruce Baker (wanting NOS or counterfeit NOS, just not typical repro)

[roy mawbey]

Nice comments Bruce. I agree Mr Szabo always advises nice information. How I agree with your comments above Bruce about 356 handling and having tip top suspension. I have never removed my torsion bars, never applied any alteration to them either. I have probably over my 46 driving the car over greased the suspension. Often after a run I see litle dobbles of grease on the garage floor! I have always adjusted the link pins and the king pins are in spec. Replaced the shocks back and front and it handles fine.
My brother Peter who ran 356 cars for years in the 60's and 70's came out with me recently in my ' A'. I admit he arrived in his 2 CV Renault run around, but on driving with me around some country roads he just could not believe just how nice the 356 handling is. And he also remarked on my 11 inch drums. The brakes are in good condition and you are correct Bruce they still work well if in good working order.

I just wonder how long can I leave my torsion bars. I just tend to forget they are there working away.

Roy

[S.J.Szabo]

[bbspdstr]

552 or 553mm (depending on which "official" Porsche book you use) long for the length of both the earliest and latest rear bars, the last of the C models getting a 22mm thick version and if memory serves, 24mm on the earliest 356s. As I wrote to S.J., the short bars were pre-A and post-C.

Over the years, a great deal of (sporadic) discussion would crop up about this topic and many private conversations (remember the phones that weren't "smart"?) gave opinions based on personal experiences. Jim Brazele at EASY would tell me they never break and could be used "forever." He suggested that he could cut those he had in "piles" diagonally in their middles and make tent pegs out of them.

Others on another forum would spout engineering theories and data. Real world experience ranges from "torsion bars never break or wear out" to "they sag over time" to "they take a set" to "torsion bars eventually break."

I have experienced "all of the above" and would like to include the front bars in this discussion. I just removed 2 sets from a later ('64) and an earlier ('55) and discovered both upper bars had a leaf broken. The '55 had been a mis-match of 5 and 6 leaves.

I would now like to enlist S.J. into determining with me the length and availability of a cross-over VW front bar(s), as I am soon going to be out of used spares of known usefulness. The fronts carry less weight but they still suffer fatigue and failure.

I do not know what other restorers think or do about such matters, but I include parts in a project that subtly impart the psychological satisfaction when the job is complete, i.e. most all cars get a new windshield and now at least the rear torsion bars and a refreshed suspension. If a person spends a LOT of money on the restoration, what's another $500-$1000? The labor is the same. If they look out through a new glass, the money spent seems more worthwhile.....same with driving that same car with a tighter suspension and a 'new' feel. Money well spent, as the only shiny new paint or chrome that may be seen will be on the dash.

The whole idea is that it's more fun to drive and enjoy a 50+ year old automobile that doesn't look or drive like a 50+ year old car! Ironically, I have had a 45 year career doing just that and that math doesn't make sense....but it's been a fun ride!

-Bruce