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My understanding of the STR (tube frame chassis) weight issue is that NASA supports a number of customers running retired stock cars from other sanctioning bodies as part of their west coast business. From what little I've been able to sort out, those guys outweigh the CSR/DSR refugees in terms of paying customers. Safety also comes into play (kind of - you can still build the ultra-light cars, you just have to race them in a different sub-class - which may still end up in the big bore race group...), as most of the "big bore" race group field is composed of racing classes centered around the larger, more powerful production cars; think Corvettes, Mustangs and Vipers - vs the "small bore" field's mass of Hondas and Miatias.

As for the V8 locost build, yes I have been following your design thread, and we are thinking about your design as one of the options for the build. I like most of it, but I'm not sure how well the safety folks will like the rear lateral links anchored to the roll cage - they sometimes can be touchy about anything other than cage tubes, belt anchors and body supports/connections being welded to a cage. It's something I'll need investigate more before we start.

I'm not actually worried at all about hitting the 1,801 lb minimum weight to avoid the power penalty with a V8. That weight is with driver, ready to race and a reasonable amount of ballast is allowed. Additional weight (and stiffness) can be added in by increasing the tube diameters or if necessary using a heavy floor. Some combination off all of this will probably be used to give us the weight distribution we want, while still requiring essentially most of the allowed ballast, allowing us to place that weight where it seems to do the most good at each track.

About the only other chassis changes I would consider, since we would no longer be constrained by the need to closely follow a seven, is rebuilding the front suspension box and chassis into a classic pair of upper and lower rectangles without regard to following the body line. I'd then blend that into engine bay. I would still finish the car with a traditional hood and front body line, but there's no actual need for the body and chassis to have the same shape, the body work could just be a supported structure. And as long as we're talking body, the STR move frees the race car from needing to use a traditional seven body; we can build an aero shell. Most likely phase one would be seven body and phase two would be aero shell; the fastest path to actually get the car racing.

Once that build actually begins to go somewhere, I'll start a build log for it.

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This is an issue I wonder about too. I'm not so worried about the safety issue, but would like to be compliant with their regulations. I have made changes so that none of the suspension is connected to the roll cage directly. The trailing arms connect to some rectangular tube, which is connected to the cage but also to floor members. The lateral links in the rear now also connect to rectangular tube which forms a bulkhead behind the driver. There is also floor tubing under the driveshaft and between the bottom of the roll hoops. The front suspension also has it's own box. and their is square tubing bracing in the engine compartment. It's within 10-20 pounds of tubing of being able to move around without the roll cage, but it wouldn't be as stiff. That additional tubing would probably make good rub strips to protect the cage.

So far as aero, Jack McCornack is considering producing some copies of his bodywork and I think you can assume he knows his aero. From his numbers it would appear to half the drag of his original bodywork. So twice the effective horsepower, that sounds good to me.

No reason to retain the taper in the frame for the Seven look, that's an easy adjustment and Jack is accounting for that in his bodywork, I believe.

I would be very interested in your continued thoughts about the body / space frame / rollcage issues, they are important to me.

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
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So in the ongoing saga of my pre-build, I may finally have managed a huge step forward. I've forced myself to maintain a "one disassembled car at a time" rule because I love all manner of interesting projects, and I refuse to own a collection full of unfinished cars I'm not able to enjoy. The milestone is that by the weekend, my Evo should finally be wrapped up and moving off to a new home.

That will mean I can finally begin on the Lotus! First steps will be to make the car run and drive mostly as-is - I need to establish some preliminary benchmarks like corner weights and basic functionality. I am hoping this phase will be fairly painless; I drove the car onto the trailer when purchased it and everything worked within reason. At this point all I really need is to do is get the brake system to hold pressure for an afternoon's worth of driving and toss in a battery. One trip to cars & coffee with a "farm fresh" sign after the benchmark gathering and I'll be ready to begin the madness.

Wow, its only taken me about 2.5 years to get this far!

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Wow, it's only been a bit over a year since my last entry in this thread. So now I'm working on 3.5 years and counting. At least I'm still moving forward, right?

I'm not sure if I covered it here or not, but the close friend who's garage we had been doing most of our locost related work in ended up selling his house and moving his family to Colorado. That left me not wanting to tear my Lotus down to it's component pieces (or start building a new race car from scratch) in what I considered temporary digs. With the housing market changing, it was time to revisit the "suitable garage" situation again, and we've finally settled on a new build space.

I was able to insulate the garage while the place was being built, so that "Great White North" essential is done. I also had the garage set up for heat during construction and built with an extra foot of ceiling height, but I still need to purchase and install a heater. I'm also planning to add AC sometime before middle of next summer; it may sound like a luxury, but it really is an essential when when the mosquitoes are so thick you feel like you're swimming through them and it's 90F (+) and dripping with humidity in the shade. And of course the garage walls are just unpainted drywall and the lighting needs to be improved, the floor needs to be finished, I'll need to add more outlets and set up the compressor .. the usual (seemingly endless) list of garage essentials. That said, it does feel great to be back in a real house with my own garage again. Now I just have to turn it into a proper work-space.

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