The Construction Diary
"Road&Track" puts the Monza SS on its cover plus an article on it inside. The dream begins!
At the Kettering Holiday-at-Home Parade, the Shriners perform formation driving in Monza SS go-karts!
I did not know they existed. How could I get one on an allowance of 75 cents a week?
Decide to make my own Monza SS rather than a custom car of my own design.
As I kept noodling and doodling, I kept coming up with more features I wanted to build into a car of my own design.
At last I stepped back and realized what I was getting myself into - I who had never pulled an engine.
I decided that my custom car would be too ambitious for a first try. The Monza would be simpler.
Besides... I have always loved the styling of the roadster, and if I only build one car, I would be very happy to be driving it!
Pick up Chevy Jr go-kart in TN. Will use body for measurements of full size car.
It looks like the fender line matches almost exactly that of the real Monza SS!
The go-kart is slightly larger than 1/2 scale at 87"x36" compared to 164.5"x64.5" for the real article.
It's time to get serious about what I will use as the chassis for the Monza SS.
I created a comparison spreadsheet of every car that I seriously fancied.
A Corvair seemed the most likely, except that it was too wide in track, rather heavy engined, and generally poor gas mileage (~16mpg).
It would take a lot of cutting, but it would be in spirit a duplicate.
The Porsche 911 was nearly right-on in wheelbase(+/− 1 inch depending on the year), track, and overall dimensions.
But, oh, the cost! Imagine buying one just to cut off the body!! The front struts were too tall, but coilovers are available.
But, oh, the cost!!!
The Sterling custom chassis was considered, but again, it seemed costly and still needed some adapting, being too long.
Surprisingly, the VW 411/412 stood out as a candidate.
Certainly it was too long and underpowered, but using the dunebuggy as a metaphor,
it could be shortened and souped up. In fact, souped up a lot!
And... the rear suspension had been properly designed (think no-swing-axle) and the track was within an inch of desired.
True, the front suspension had those horribly tall struts, but other than that, looked to be a good solution.
In fact, the Hillman Imp was noted for its handling even though it was rear-engined, and it had about the same type of suspension as the 411 (read it here)!
So I had my choices narrowed down, and here is how they stacked up:
88" wheelbase / 53" track
front suspension: double wishbone + longitudinal torsion bars
rear suspension: double wishbone + coils and shocks (not coilovers)
Corvair engine: 140 hp, 4-barrel (originally), 6-barrel currently
Seats fixed, pedals adjustable, steering moves in/out (about 4")
too-low Cibie headlights & Corvette-style taillights
non-street legal windscreen
no top, integrated rollbar added in '65
1) '65-'69 CORVAIR
108" wheelbase // 55.5/56.5" track fr/rr
+ Corvair engine
+ good rear suspension
− requires upscaling SS design 105% to use Corvair rear track
− poor gas mileage (15 mpg)
− adapt new front suspension?
−> biggest problem: resizing body
−> biggest negative: gas mileage, weight of engine/transaxle
2) PORSCHE 911/912
87/89" wheelbase '64/'69 // 53.8/52.8" track fr/rr
+ near exact wheelbase & track
+ roller available
+ 911-specific coilover suspension available (sort of)
− must cut away all but floor pan
− engine too tall because of fan
− add frame reinforcement (unless a Carrera)
−> option: mating T4 engine to transaxle & suspension
−> biggest negative: probably expense overall, front struts too tall, cooling fan too high
3) VW 411/412
98.4" wheelbase // 54.2/53.2" track fr/rr
+ use existing T4 engine and rear suspension (only 1" wider track)
+ T4 can be rebuilt for 100 to 200 hp
+ T4 engine+trans is 80 lbs lighter than Corvair
− replace front strut suspension
− wheelbase: shorten chassis (10.5")
− add frame reinforcement
−> biggest problem: new front suspension
−> biggest negative: not Corvair-powered like original (not a negative, really)
4) CUSTOM CHASSIS
+ match exact dimensions: body, wheelbase, track
− cost: custom design & build
−> biggest problem: near complete ignorance of what I am facing this way
−> biggest negative: don't know yet
−−−−−−−−−− CONSTRUCTION DECISIONS −−−−−−−−−−
ENGINE: T4 '76 Vanagon rebuilt to 2056cc/127hp
WHEELS: 13x5.5 aluminum Scirocco
HUBS: adapt knock-off spinner and back plate
HEADLIGHTS: Hella 3-1/2" bi-xeon or bi-halogen HID
TAILLIGHTS: 3-1/2" '58/'61 Chevrolet "beehive tail lenses / '62 F-85 taillight bezels
WINDSHIELD: custom formed, adjustable height - 5"->12"
WIPERS: wipers mounted to windshield or convertible top?
SEATS: bucket, adjustable, back folds down
TOP: removable roll bar + top panel (Targa style) or adapt C3 Corvette convertible top
STEERING WHEEL: telescopic, tilt, removable
GAUGES: 6 like in original
HEAT/COOL: VW 412 gas heater / front vent
Check out 2014 for more progress!
Dane Northrup at DI Polishing (on Facebook) - polishes aluminum automotive parts!
Vince Sprague at Horizon Machining in Berthoud Colorado (970 532-2458) -
a top-notch machine shop, and car guy as well. Built his own sand rail.
Orignal Customs (and on Facebook) - engine rebuilder and more!
Poudre Sport Cars - performance, sports cars, and exotics - repair, track-ready prep, & customer-oriented service; source for transmission & rebuild
VRBA's in Fort Collins, Colorado (970 484-2011) - air-cooled VW specialist on the north Front Range; service,parts, and source for donor vehicle and engine
Mel Francis - car builder extraordinaire! He built a "production replica" of the Monza
and is currently working on doing one of Syd Mead's "Sentinels"... and MORE!
(L,C,R) The Monza GT and SS beauty shots
Note the headlight clamshells on the SS. That indicates the original (and short-lived) headlight solution
(L) A 3/4 rear view - very windswept. The styling combined creased lines with rounded surfaces.
(C) Circa '67. Note the Cibié headlights now and the integral roll bar.
(R) The Kamm tail was aerodynamic. The fender protruding exhausts were a nice touch.
But the only muffler on them was a short glasspack between the tip and the exhaust ports.
It must be noisy!
(L) This view gives some sense of how low is the car. It was, after all, designed as a true sports car a la Cobra.
(C) The original Monza Jr made for Bill Mitchell. It was later produced by the Rupp go-kart company for GM marketing and finally for general sales.
(R) Another engineless prototype was created as a study for a production version.
Note the bumpers, wider doors, windshield, and 14 inch wheels versus the orginal 13 inchers.
The Kamm tail was not as recessed and flatter, and looked very much like the '65-'69 Corvairs.
4th ROW - DETAILS
(L) Hood emblem
(C) Fender Emblem
(R) Alloy wheel (I think they made a mirrored-image set for left and right)
(R) Cockpit - note the seat cushion apparently sprung up to aid getting in and out.
Research & Comparisons
Spreadsheet (pdf format) comparing different vehicles to determine the best (easiest, cheapest) donor car.
The Porsche 911 seemed the best, but just try buying one even as a roller! Labor and time I have, money I don't.
Buying a kit chassis was seriously considered. And of course a Corvair was definitely considered!
I will be able to tell you if I made a good decision after I'm done.
(L) Monza SS / 1960-64 Corvair
(C) Monza SS / C2 Corvette / C3 Corvette
(R) Monza SS / 1968 C3 Corvette. SS front view is approximate.
(L) Monza SS / Porsche 911 long wheelbase
(C) Monza SS / Pontiac Fiero
(R) Monza SS / Monza Jr go-kart. Yellow outline is taken from SS profile.
(L) Monza SS side elevation.
I scaled up the centerline to seat bulkhead and superimposed the wheels & fenders according to the published dimensions to get a sense of an side elevation view.
(C) Monza SS / VW 411 fastback sectional view
(R) Monza SS / VW 411 after cutting down. Note the front struts are WAY too tall!
My first thought was to replace them with coilovers, but that is easier said than done.
The wheel bolt pattern is for the 15 inch wheel, so that would have to be replaced.
Building a top wishbone and mounting it is daunting to me, and how does one attache it to the wheel?
Better to find a front end. The Corvair suggested itself as a good direction, being a complete, non-engine-supporting unit.
(L) Example of perspective reconstruction 3-view, using the wheelbase as my datum line.
The photo was reconstructed in Hugin, then the three views placed and scaled in Adobe Illustrator.
But deriving dimensions is still difficult. One has to determine a set of points in the same plane.
(C) The base photo used for perspective reconstruction
(R) And here is a work-in-process line drawing based on the reconstructions.
There is still lots of work using multiple photos to get a best-average set of lines.
The Donor Vehicle
(L) The VW 412 as I found it after sitting for 20+ years.
(C) (After having it towed home) Driver side
(R) Passenger side - very close to an elevation view
(L1) 3/4 front view, and just cute enough that my daughter wanted it for her own
(L2) 3/4 rear view
(R1) front view - note the skinny tires
(R2) rear view