Building a 1/12 Ford MkII Roadster, the'66 Sebring Winner

[ssobier]

THE PROJECT
This is a build of the 1/12 Trumpeter Ford GT MkII kit, converted to represent the 1966 Sebring winning roadster driven by Ken Miles and Lloyd Ruby. The Trumpeter MKII has been around for a while now, and I assume most modelers are somewhat familiar with it. It is a kit of many faces, some good, some bad and some ugly. While I want to correct some of the kit’s (many) shortcomings, I am not striving for an “Ultimate Build”. The intent will be to use as many of the kit parts, as possible-either as-is or modified, accept some of the kit’s lesser shortcomings, and add some detail here and there along the way.

THE PROTOTYPE
The Sebring roadster started out as an experimental aluminum chassis numbered GT/110, and was built up in Bruce McLaren’s shop as a 427 engined Group 7 sports racer. It was unsuccessfully campaigned during 1965 in several US west coast races as the Ford X-1, driven by Chris Amon.

At the end of 1965 the car was sent to Kar Kraft in Michigan to be strengthened and modified to MkII specifications, and was then sent to Shelby American International to be used as test vehicle. SAI decided to update the car to the latest MkII body configuration and entered it at Sebring for Miles/Ruby to run with an automatic transmission. After breaking two automatics in practice a regular four-speed was fitted for the race, and when the Gurney/Grant coupe failed in the last corner of the last lap the roadster was there to claim an unexpected victory.

After the race the car was shipped back to Shelby’s shop with the intention of preparing it to run at LeMans, but it was found that the rough Sebring circuit had given the lighter aluminum chassis such a beating that the roadster was retired. Later, it was unfortunately destroyed by SAI to avoid the payment of import duties.

THE MODEL
I began with the best part of the kit, the body, and started the conversion by cutting away the top and windshield frame. The top was cut off at the back, with the cut being made in line with the rears of the doors and the front of the fire wall, and the windshield pillars were cut off flush at their bases. No turning back now.

The side window frames were cut from the doors flush with the bottom of the windows. The roadster’s windscreen was narrower than the coupe’s, so I added curved filler pieces on each side of the windshield base to make the transition.

I also cut down the kit’s dash panel assembly to match the new windshield configuration and added flat panels to the top of each door where the windows had been removed. The seats in the X-1 did not have the signature ventilation holes and grommets normally seen in Ford GTs, so I have sanded them off of the kit seats.

Steve Sobieralski

[Daryl_Huhtala]

Note that the doors will need reshaping for the longer ramp into the lower air scoop on the sides.

[f40]

Very cool . Should be a very interesting build. Looks like your off to a good start.Do yourself a favor and get a set of Gt 40 Tires from Icon models. You wont regret it. They are much nicer than the kit tires.

[ssobier]

Note that the doors will need reshaping for the longer ramp into the lower air scoop on the sides.

Yes, I know. Still thinking about how I am going to do that.

Do yourself a favor and get a set of Gt 40 Tires from Icon models. You wont regret it. They are much nicer than the kit tires.

I have seen photos of the tires and they are very nice. Something to think about.

I have turned my attention to probably the worst aspect of the kit, the rear chassis and engine compartment. Where to start? Trumpeter simply left out much of the structure of the rear chassis, and much of they did provide is fictitious If the kit is built out of the box there will be large gaps and voids where there should be solid chassis tub. Much of the rear of the chassis will have to be scratchbuilt.

I began by adding sheet plastic to the rear deck of the chassis to more correctly reflect the prototype configuration. Angular extensions were added at the rear, the engine bay was narrowed and the top of the tub was extended forward to the line of the firewall.

One of the uglier aspects of this kit, in my opinion, is Trumpeter’s excessive use of chrome plating. Very few parts should be plated-the engine valve covers, headlight and taillight surrounds, door latches, body latches, exterior dome lights, some interior trim and maybe the knock-off hubs, but that’s about it. Yet, there are five full sprues of plated parts in this kit. Everything is chromed, even the fan belt, it reminds me of some of the car kits I built as a kid in the sixties. Getting rid of it is not a huge problem, soaking the parts in Wesley’s Bleche-Wite, or something similar takes it right off. Unfortunately, the plated parts are molded in a shiny ivory-colored plastic that is almost completely immune to plastic cement and is thus extremely difficult to glue securely.

Above is one of the easier fixes. The bottom of the rear subframe is much too deep, but this can be easily cut away. Still a little heavy, but a much more correct appearance. Note that the upper frames, which carry the FIA-required luggage boxes, have been stripped of chrome. On the real car these would have been painted the chassis color, either blue or black, so chrome plating was a completely inappropriate finish for these parts.

The photo below shows a relatively minor item, but one that is somewhat indicative of this kit. In addition to being incorrectly chromed, the exhaust megaphones are molded with a large void in the bottom. This is fairly easily fixed with a section of Evergreen tubing, but it’s the kind of thing you would expect to find on a kit from the fifties or a toy, not on a modern, supposedly state-of-the-art kit.

Steve Sobieralski

[EricCole]

I really like this project and looking forward to watching this work in progress. The kit is on my list to build this year as well. In fact I just ordered the KA full detail set and Icon Models tires this week from Kevin at Stradasports.

[Dino]

The roadster is a nice conversion, don't have to reinvent the wheel to do it.

[ssobier]

In the photos below the rear of the car has been dry-fitted together as built from the kit. Note how the area immediately behind the fire wall is wide open and that the rear part of the tub is almost completely missing. The ancillary details such as the engine mounts, oil filter, catch tank, etc. are all totally bogus as well as being originally chromed. The black pieces on the sides are the towers to which the ends of the top radius rods are attached, but on the real car these actually sit on the top of the tub. The black piece across the front of the compartment holds a nut to which a bracket at the front end of the engine is screwed, a fictitious arrangement as the real car had no such bracket or front engine attachment point.

The kit dampers and upper suspension arms are attached to a cross member, which is supported by the transaxle, similar to the arrangement on a Lotus 49. On the real car this cross member is part of a complete structural frame, through which the gearbox protrudes, that forms the rear of the chassis tub. The photos below show the rear frame, scratchbuilt from plastic sheet, which has been constructed to utilize the kit cross member.

Below are photos of the rear frame attached to the chassis, which has been rebuilt using plastic sheet to more accurately portray the actual car. The engine bay, the space behind the firewall and the rear of the chassis are now completely enclosed. The sidewalls of the engine bay, where the engine mounts attach, have been somewhat simplified but that will be very difficult to see once the engine is in place.

I should say that most of this work is being done by eye from whatever photos I have been able to find of these areas. It is, quite frankly, educated (hopefully) guesswork.

Steve Sobieralski

[hquednau]

What a neat idea for a project- I am looking forward to more!

[ssobier]

The engine/transaxle assembly is another glaring shortcoming of the Trumpeter kit. It is not only poorly and inaccurately detailed, but also considerably undersized. The first indication that the engine is too small comes when it is test fitted to the chassis. In the real MkII, one of the modifications that had to be made to the GT40 was a bulge in the firewall to accommodate the greater length of the 427. Even then it was a very snug fit. As you can see in the photo below, there is a rather substantial gap between the front of the engine and the (unbulged) kit firewall. The second clue is at the back, where the rear casing of the gearbox should be quite close to the rear frame work, with the transaxle oil pump just protruding through it.

I don’t have any scaled or measured drawings of the 427/transaxle, but from what I can determine the overall length of the assembly should be about 4.75 inches. The kit engine and transaxle are just over 4 inches long, or almost eight scale inches too short. I cannot tell whether the engine is undersized in all dimensions or is just too short, but there is a serious discrepancy in length of about 15%. The best solution would be to scratchbuild a new correctly scaled engine and transaxle, but I have neither the references nor the desire to do that (I did say at the beginning that this was not an “ultimate” build), so I am going to use a work-around.

First, let’s look at the engine itself. The photos below show it partially assembled from the kit.

All of the ivory colored parts have been striped of chrome, that includes the upper engine block, front casing, alternator, water pump pulley and belt, piping, fictitious front mounting plate and transaxle rear case. The number of these parts that were actually chrome, or bright metal, on the real car is zero. Trumpeter has also thoughtfully prepainted the intake manifold and lower engine block gold, a color that is correct for neither as the manifold was unpainted cast aluminum and the engine block was painted blue. Another somewhat amusing gaffe concerns the piping seen at the front of the engine. The connections at the bottom were for oil lines and those pipes should go to the oil tank at the front of the car and the oil cooler in the engine compartment. But two of the pipes go to the top of the engine, which is where the water hoses were connected, so Trumpeter has effectively cross-connected the oil and water systems.

In the detail photo above you can see a large void at the front of the engine behind the water pump pulley. The should be a water pump there, but there is no water pump, or any other part, provided in the kit to cover that hole. If you build it OOB that’s what it’s going to look like. In addition to the water pump, other major missing components include the distributor and starter, all pretty basic items and details you would expect to find on a good 1/43 kit, never mind 1/12. Parts that are there, but very poorly represented, include the alternator, oil filter, catch tank and engine mounts.

The photos above show my start at the engine improvements. So far, I have scratchbuilt the waterpump, pulley, alternator bracket and new engine mounts, and enhanced the kit alternator and crank pulley. The top view shows my solution for the short engine, which is a spacer to elongate the bell housing. This is by no means correct, but it will move the engine forward to where it needs to be and the spacer should be effectively hidden by the exhaust system and chassis. I still need to determine how to deal with the too-short transaxle.

Steve Sobieralski

[PeteJ]

Probably too late, but here is the real deal under construction at Holman Moody. It is a "Continuation car" made from the original stampings and to blueprint specs.