Vorshlag Build Thread - 69 Camaro Pro Touring/Track Car

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Project Update January 2nd, 2016: This forum post update covers work we did to the 69 Camaro in October of 2015. This included front splitter layout, front splitter structural mounts, some suspension and shock questions, front brake ducting, air intake tub and airbox, upper grill, some initial radiator ducting, and more. Some of the "work" was just conversing with the customer to finalize the look for certain things, or reasons why we wanted to not use an existing part, which I won't bore you with here. Just the pics of the work completed and the reasons behind the parts or design choices.

Just a quick shout-out to Lateral-G forums. This build thread was added there after a moderator reached out to me last week and said "bring it". If there's another forum where you think this build thread would be welcomed (and you are an admin or moderator there) please send me a PM and we'll take a look.

LOWER SPLITTER DESIGN & FABRICATION

There have been some hours spent on the front splitter design over the past 3 months, perfecting the dual plane splitter design that we have come to now. The work below was from early October and the design based off a lot of back-and-forth discussion with the car owner and us, where we refined our engineering / aero / fabrication goals and merged them with the aesthetic look he had in mind.



We took inspiration for the final splitter from a certain racing series where some recent rules changes have allowed for better splitter designs - and where multi-plane splitters on sedans and coupes has arisen (one example is above left). We do caution folks when looking at pro racing series for aero design inspiration, though, because this is one area that is almost always heavily regulated by strict rules. Race engineers have to come up with lots of tricks to exploit rules loopholes, which might not apply to your build. (exception: World Time Attack has almost unlimited aero rules) This 69 Camaro isn't really being built for any racing class (after long discussions with the customer) so we can "go nuts" with aero. This car is still being built around a budget, and looks do matter, so the customers "intended use" makes some of the "unlimited" front aero tricks unfeasible (see above right).

There was a bit of compromise on both sides for the splitter and front valance. In the end (it is nearly done now in January) I think the splitter and front end looks amazing, is very strong, should make ample downforce, push air past three heat exchangers, feed two brake cooling ducts, and keep the intake airbox filled with high pressure ambient air. All sorts of systems are tied into the splitter so this was a pretty big chunk of this project.



Jason has a specialty in fluids engineering so he worked directly with our fabricator Ryan to lay out the airflow paths and put the splitter where it needed to go. They also discussed splitter length, as we tend to run more extension than others. Why? Because we've tested it, and a longer chord works better in most cases.



Vorshlag has built and tested a number of splitter designs for a number of different cars. We used 3 different splitter designs and lengths on the 2011 Mustang above, which I raced in NASA competition events for 5 years. We were told by some that the 10.25" extension on the splitter shown above "wouldn't work", but in fact it worked too well and overpowered the rear wing we ran at the time.

The long splitter length and low height made loading the car onto our trailer a total bear (even with 12 feet of ramps), and scraping the pavement driving around in even a somewhat smooth paddock was common. We later made another splitter with only a 6" extension past the nose, and that was much more user friendly (even somewhat streetable), and still made ample front downforce - when coupled with a lower grill inlet duct, a ducted hood, and blocked off upper grill. I will come back to that set of "grouped mods" below.



Ryan took Jason's engineering direction, some "inspiration" pictures I provided, and his own experience and built a mock-up of the lower plane of the splitter in MDF. This was built with a certain amount of extension past the front bumper, and fixed at a certain height from the ground - not too close to make it impossible to load on a trailer or get taken out by a simple off track excursion, but not too high as to ruin the ground effect we're going for. We sent several images of the mock-up to the customer, then moved into metal when he approved.



Some have questioned our use of aluminum plate for front splitters in the past, but we have explained that in detailed replies before. Short version - there are 3 materials we feel are appropriate for front splitters: plywood, aluminum plate and carbon fiber. We don't like Alumilite or other corrugated "sign shop" materials for a number of reasons, mostly because you can permanently deform that between two fingers. This stuff tears easily and the force of air pressure alone has made more than a few Alumilite splitters fly off - one of which then caused a crash on the car if flew off of, as seen in a certain high profile race event a year ago.



Plywood has its place in racing (usually in lower budget endurance, W2W or Time Attack cars) and we've even used plywood on the Hillclimb Subaru, shown above. We chose plywood here because of high level of abrasion on the paved Pikes Peak mountain hillclimb course + the low cost for each unit allowed for multiple spares. Carbon is the lightest/strongest choice, but too pricey for anyone but pro race teams to use and beat on (and we are not a "composite shop"). That leaves aluminum - which is easy for us to fabricate, has a relatively low material cost, and has a good strength-to-weight ratio. We could talk for days about the pros and cons of splitter materials, but I'm going to leave it at that so we don't get too sidetracked.

continued below