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70.197.0.69
A minor mystery solved, last time I was at Canepa Motor Sports I saw this formerly 3.6L 911 (993) motor (engine) that had been cut down to four cylinders, wondering why anyone would do such a thing, but I never asked. Now I know.
Follow Ups:
Well, if they have a 917, or 962 hanging around... or a 904, or 910...
But something going into a 356 tub? Meh. :)
The 959 is the one Porsche I never wanted to see but always dreamt of owning!
It is kinda ugly but it is the only car you can use to chase Ferraris around the track but change tyres, press a button and you can chase anything off road.
During its very short lifetime the 959 won the Dakar rallye and its class at LeMans!
It's always changing
Always like the lines of this roadster.
What fun!
you don't have to row it along, and keep it on the cam!
It's a speed and acceleration type's car. A show-off's car.
REAL Porsche 356's are 'driver's' cars.
People who know how to get the most out of a car, and not crash it! Keep it on the cam, see the next corner, and IF you know the corner max it out. And if you don't, go 'tippy-toes quick'.
I learnt to drive to the limit, on swing-axle Beetles, it is a really good school.
I'm not quick enough any more to drive at 8-9/10ths but I can manage 6-7/10ths, most of the time, still.
Patricia can't cope with anything more than 3-4/10ths.
Warmest
Tim Bailey
Skeptical Measurer & Audio Scrounger
That's half the fun! Racing motorcycles also gives you good "seat of the pants" reactions. Keeping on powerband, knowing when to shift, how the thing reacts to power input & braking.
Did like this BMW boot camp video with Brian Redman.
-----
Love that 3.0CSL but here is the reason that that Beemer never won anything in Germany:
This has 10% less power than the CSL but also 25% less weight.
Edits: 03/06/17
...drink gas like you could afford to buy it.
I'm really liking the overall look of this little class racer Porsche. Nicely styled. Yet I'm also thinking it could use just the right set of aluminum wheels to really make it an eye grabber.
Then again, if you can afford that Speedster, the gas budget probably isn't an issue.
-Steve
Love it, just as is.
But, could do without the stone guards on the head lamps.
I assume that's a side mirror over the "Speedster" logo ?
Dean.
reelsmith's axiom: Its going to be used equipment when I sell it, so it may as well be used equipment when I buy it.
I like that it has the original german bumpers and not the ugly 'export' ones with overriders.
Not so keen on the mesh covering the headlights.
I don't know. Bet ya cruising down the hwy 65-70 it'll get around 20+ mpg.
As far as the wheels go, there perfect.
Parts would prolly need to be custom engineered. The 587/2 and /3 DOHC 356 GT engines are hard enough to keep running.8^)
Edits: 03/04/17 03/04/17
"Cut down to four cylinders" is incorrect, my bad.
The engine link says 5 main bearing crank. That would mean that EACH piston is braced by 2 main bearings. The same way an inline 4 cyl would typically be constructed. Although for 'light' duty, a 3 main bearing configuration might do as well.
As for the T6 in the alloy designation? That's the heat treatment regime. In 6000 series aluminum, which is IIRC a simple silicon (and?) alloy, that brings it up to roughly mild steel tubing standards.
I don't know what alloy they ARE using for the block. But some series of Aluminum ARE excluded since they are NOT heat-treatable. Like 7000 series, for example.
A little TOO much information about Aluminum Alloys and heat treatment.
Too much is never enough
They are using 356 Aluminium which is an alloy for casting. the 4 digit ones are for wrought aluminium.
3xx cast aluminium contains silicon and copper or magnesium.
T6 means it is heat treated and artificially age-hardened.
After casting it is left to cool down and then it is heated to just below the melting point for a set time (an hour or so), quenched and then heated again to a lower temperature and kept at that for some time (quite few hours).
Although no doubt coincidental it is quite apt to use 356 Al for a motor that goes into a Porsche 356 of the same name. ;-)
Didn't realize a different series for wrought V casting.
Sounds like the 356 alloy is similar in composition to something from the 6000 series, which is also heat treatable. Uses for the 6061 variety includes stuff like Bicycle Frames which are than heat treated to the T6 spec. Roughly ends up with properties (but no fatigue strength) similar to a Mild Steel Tubing.Heat Treating is an ART. But once you have it figured out, and the proper equipment, you can let a computer do it.
I first became interested in this stuff when working in semiconductor manufacture where the 'metalization' layer was Aluminum /1% Silicon. The Silicon was the highest amount which would NOT precipitate out yet had an electrical use at a later step called 'sinter' or perhaps 'anneal'.
I personally do not like Aluminum in some uses. You need more of it than simple ratio of weight to another metal would indicate because it has NO fatigue strength. Each stress cycle eats into the ultimate lifetime of the structure. This is unlike steel which has an essentially limitless lifetime IF you never stress above the fatigue limit. A few other properties spring to mind, but that's for another discussion.
One time when working on a vacuum system (hi vac, not the one for your house!) we had an ARC in a chamber with aluminum fixturing which ALSO contained Hydrogen Gas. BOOM! When trying to fix this mess, (let te new kid fix it) I tried a FILE on what was formerly an Aluminum piece. Ever heard of Hydrogen Embrittlement? Neither had I. But this stuff was now harder than my file and I had to use OTHER means to make the fix.
ADDED LINK to compare A356 to 6061 Aluminum Alloy, both hardened to T6 standard.
Too much is never enough
Edits: 03/06/17
Once upon a time I was an aluminium welder/fabricator working mostly with 6061 T6 pipe.
Kinda like to work with aluminium but I wouldn't want an aluminium framed bicycle.
Due to the lack of fatigue strength they must be very stiff to avoid catastrophic failures and because of this they are uncomfortable.
Imo titanium is the best frame material, it has god-like fatigue strength!
Back in the early days of bicycle suspension there was one that did away links and bushes and relied purely on the titanium tube flexing. AFAIK there were no failures but travel was restricted to a couple of inches or three.
Just pray that you never have to drill a hole into that stuff. Titanium work hardens like you wouldn't believe and you'll be forever sharpening drill bits!
Titanium, ESPECIALLY the very special alloys of 3- 2 1/2 and 6-4 are amazing in a bike frame.
Real LIVE yet impossible to break or wear out.
I don't know that 6-4 can be drawn into a tube, but is hi-pressure WATER cut for dropouts and a few other flat pieces.
The first ones were made from CP Titanium and didn't fare well, maybe because of oxygen in the welds? I don't know.
But by the time somebody bought Surplus Aircraft Hydraulic Tubing, the race was ON.
I saw a Litespeed or some other VERY hi-end Titanium TANDEM when on holiday once. Immaculate and the welds were perfect.
The ULTIMATE bike metal just MIGHT be Berylium. Too bad that it is difficult to work with and is even toxic in some forms. Not to mention $$$$
My brother worked Long Haul trucking for years. He told me about the RAVEN trailer which is an Aluminum construct. I argued with him ENDLESSLY about fatigue and that they won't save THAT much weight because they'd have to use so much MORE of it than the simple weight difference would indicate.
Same reason Aluminum bikes ended up as 'Big Tube'. And fairly thick walls, too, to prevent 'Soda Straw' breakage.
I rode and EARLY Vitus Aluminum frameset. Small diameter and glued together. It was like riding a screen door. Real wimpy and gave me a REAL here-we-go feeling.
Give me a bike made of Old-School Reynolds Mg-Mo and I'd be happy. Most persons, even in the bike industry, don't know that the consumer 531 was metalurgically the SAME as 753 but the higher strength 753 was work hardened or heat treated and could be made quite a bit thinner without sacrifice. Racers like the live feel and lighter weight framesets from the 'racing' tube sets.
Too much is never enough
753 is heat-treated a pain to work with.
I used to be a brazer at a cycle manufacturer for a year or so. There were two guys who were accredited by Reynolds (they were just down the road from us) to work with 753 but they still had a huge failure rate due to the steel cracking whilst cooling.
My preferred steel tubing is Columbus Nivacrom. About as strong as 753 but a LOT easier to work with.
Before they introduced oversized headsets Cannondale bikes had a racing lifespan of <6 months before failure. Can't imagine it is much fun coming down a mountain only to have your headtube separating itself from the frame halfway down!
Those guys at Litespeed are quite good. One of the very few welded frames where when I looked at them I didn't think 'I could do better than that!'.
Shame that titanium will never get any cheaper despite being one of the most abundant metals around. Most titanium is used in the form of TiO2 to produce white pigment but turning TiO2 back into Ti is rather difficult and thus expensive.
Speaking from a strictly Metallurgical view, I'd like to see something made from one of the older EXCELL tubesets. This had some Nickel and other less common alloy metals. It was VERY strong and had a good modulus and high fatigue limits.I don't think I ever saw a small-headset 'Dale. By the time I tuned in, the entry level SR300 was all big-tube, really stiff, and with the ride you'd expect.
The trick with the racers is Constant Inspection. BEFORE every race, if any crashes and at anybody WHIM. I've got the X-Rays to prove it.
Want a metal study that's calculated to drive you NUTS? Check out the steels (mostly Stainless) which are used in KNIVES these days. My knife is one of CPM S30V which is a VERY tough alloy made from a powder, than sintered / hot pressed. Micro-Grain structure is almost invisible. Thank goodness it stays sharp so well, 'cause it's a bear to Resharpen.
SEE LINK: and let the nuttiness begin
You got me thinking and the name that popped up about Early Ti bikes was Gary Helfrich? I think he founded MERLIN and was instrumental in making the first really successful Ti framesets.
Too much is never enough
Edits: 03/07/17
'dales always had big tubed frames but early on there were only 1" headsets.
Cannondale had to swage the down tube to make it fit the head tube but for reasons I don't understand 'dale was late to the party when larger headsets appeared and waited a couple more years to fit them.
That is the sexiest Porsche ever made!
"I don't know. Bet ya cruising down the hwy 65-70 it'll get around 20+ mpg."
That sounds about right. Then again that little motor is likely less than 2 liters. You'd expect around 30 mpg hwy if it had the original motor.
-Steve
Horses need to be fed and 3x times the horses for only a 33% reduction in mpg is pretty good in my book.
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