A crazy frenzy of activity these past few days. When we started up the engine I noticed it was running quite rich and not sounding exactly happy. Just a hunch, but having had engine issues in 2012, and knowing that we overheated this one twice, we had to know.
So we took the car to Portland Speed Industries again and put it on their dyno. First pull confirms that something is not right – we’re at only 400hp, or a full 150 hp down! I have a moment of quiet panic, then we start looking at data. Jason says that there is no boost. That’s actually good, because it’s likely fixable. Tristan starts looking around behind the firewall and sure enough – a connector was unplugged when we switched belt tensioners and never got reconnected. With the connection made, another pull confirms the problem is solved. We’re back up to 550+ hp at the wheels. The car sounds good with no mufflers – here’s a video.
I believe a good part of the engine surviving overheats is the fairly conservative tune that Jason did during our first dyno session. He backed the ignition off to where the engine never activated the knock sensor, giving it an extra margin of safety. Really great to be working with someone who understands our goals and doesn’t just crank out max power no matter what.
Now that we feel better about the engine, it’s time to put everything together again. The bodywork came back from paint yesterday and the assembly has begun.
We’re running with full street lights, windshield wiper, the works. This is truly a car anyone could buy and drive on the road (when assembled as a kit). There are some evolutionary steps from our previous standard cars and the main one is the wings package. I’ve been meaning to design and make one for quite some time (years actually) but other priorities kept getting in the way. The race is forcing my hand now and of course it’s all last minute.
The rear wing was put together by Marcus at Central Composites. He also made skins for the front one but it would be up to me to actually make the wing. It’s a bit complicated in shape and how it mounts. I designed the parts in SolidWorks and made sure everything fits in the virtual world. The angles are very odd and there is no good way for me to machine or otherwise fabricate the needed shapes. Perfect job for 3D printing though where there is no need to be constrained in shape by manufacturability. I’ve been talking to Robin at Ultimate3D about doing something for our cars and this was the right opportunity. He was eager to demonstrate what they can do. So I sent the files yesterday and this morning we have the parts – printed in carbon-reinforced nylon.
These are basically wing ribs and endcaps combined. Their purpose is to locate the wing skins in space, attach them structurally to the steel tubular spars, and define the overall shape of the wings. In case that wasn’t enough, the parts also serve as mounting surfaces for the endplates, with holes for helicoils designed in from the start.
Now it’s time to build the front wing while Mark fabricates mounts for the rear one (I designed and machined the clamps for rear wing mount tubes yesterday).
I trim the skins in place and then we bond them in with special adhesive. Everything here is an experiment piled upon another experiment. The goal is to arrive at a production solution that can be retrofitted to both existing cars and future ones, so it needs to work with both current and new bodywork. SolidWorks confirms that it should fit in both applications, and earlier CFD runs show its effectiveness. Now we just have to install and test. Takes a few hours but the car is now with wings and is ready for all the sponsor logos.
Now I need to design, fabricate and install all the endplates, including the nose-to-front-wing interface. Compared to everything that’s already done, piece of cake.
We are leaving for Colorado either tomorrow afternoon or, at the latest, early Saturday morning. Both trailer and van got some maintenance so hopefully the trip will be uneventful.
Honda just announced that they will be running an LMP car in this year’s event, with a driver whose experience includes F1. It will be interesting to see how they do, and how we do compared to them. Should be exciting 🙂