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COMPOSITE DOORS
The dreaded Scope Creep started to happen here. When this '67 Mustang project came in it was still a "street car that could occasionally do track events". It had a 4-point roll bar, full interior, and working air con. As the project progressed the owner quickly re-focused his already listed safety goals to match the increased performance we were adding. To mate the power output of the LS7 the safety goals went up to match. Instead of a reconfigured 4-point roll bar it was time for a proper roll cage, and by then the car became a dedicated track car "that can be driven on the street".
After the cage had begun we talked about door bar options - a simple "X" that allows for an interior door panel, or a more roomy NASCAR style door bar, as shown above. After seeing the difference in person, and noting the lateral room gained when we push the bars out to the outer skin of the door, Adam wanted to go ahead and use NASCAR style door bars. That means ditching the door panels, the door windows, and the interior.
We asked him several times if he was SURE that's what he wanted - because going this route shrinks the number of people willing to buy any car when it is completed. Caged race cars are harder to sell than street cars with some tasteful mods. But as you can see by the other mods that have been added as we went along, this has turned into a more serious track build. And the door bars will add a lot of side impact protection and extra room for both the driver and passenger.
Adding safety usually means adding WEIGHT - which is always the enemy of speed. The OEM steel doors are always heavy when chock full of crash beams, window mechanisms, glass, and speakers. These were no different at 76.0 pounds each. So when he asked for NASCAR door bars, the need for OEM door impact protection went away - so I suggested these cost effective composite doors from VFN.
These fiberglass doors were purchased and weighed in at a paltry 14.5 pounds - and that's before we clearance them for the cage's door bars. This weight savings will be about a 123 pound drop, which should offset the weight gain of the full cage over the 4-point (and then some).
We have used VFN body parts before and they fall in at the more affordable end of the spectrum of quality, lightweight composites. Way better than cheap import stuff, but not quite Motorsports Dry Carbon level. Evan checked then marked the mounting holes (dimpled in the mold) and drilled them for the door hinges. We will use the OEM hinges without the return springs. Evan made some templates from these hinge mount holes, then Myles CNC cut some
backing steel plates for "doublers" that go on the inside of the door structure.
Evan then tack welded nuts to these plates, which are riveted to the door structure. Makes installation and removal a breeze and strengthens the part of the door that sees the highest loads - the hinge points.
A little time was spent "fitting" the doors, but with aftermarket composite front fenders and composite doors from another company, they don't "play nice together". As is the case with some composite parts, both the Maier Racing composite fenders and VFN doors are made a little "long" so you can trim them to fit. We are not a body shop, so I will deliver the chassis to our painter (as soon as the suspension is done enough to let it roll into my trailer) and have him adjust all of the panels on the front of the car, from the doors forward.
The body shop can trim the doors and fenders to have a better fit so we can open/close the doors. Until then we will either have the doors -or- the front fenders on, depending on what we are doing. You won't see them both installed from here until they are properly fitted.
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