William Toet is the former Head of Aerodynamics for the Sauber F1 Team, and is one of very few F1 engineers that has been willing to impart with his vast wealth of knowledge. He is an engaging speaker and covers a fascinating array of motor sport topics.
Here he speaks about the design, performance and aerodynamics of Formula 1.
With thanks to the HKUST Jockey Club Institute for Advanced Study
I have been following William’s posts for a while now as they are amazingly insightful and deeply technical.
Here is his fantastically easy to read explanation of duct design, and the magic number you need to aim for when working out expansion angles.
William explains; “Ducts are there to capture air from, ideally, a clean, high energy source and conduct it to the place it needs to be used (usually for cooling of some sort, or for “feeding” an engine).
Expanding the air gently is the right thing to do. Often there isn’t the space to do this realistically but here’s an example of a duct that benefitted from making space.”
Home-Made Corner Weight Scales
Many years ago I went to TAFE with a friend of mine who we all knew as “Dangerous Dave”. I struggled in my Statics subjects, whereas Dave was a gun at it. He quickly worked out not only how to solve the problems in class, but how to apply the methods in real world situations.
Dangerous Dave concocted a rig to measure corner weights. While not exciting in itself, (there are after all many examples of homemade load cell systems on the internet) what made Dangerous Dave’s design so interesting to me was its simple elegance and an in-your-face use of science.
Dave’s take on corner weight scales was to take four cheap bathroom scales and work out how long the lever needed to be to allow the scales to operate within their functional range.
This turned out to be very simple. On a beam 1000mm long with a point load at 800mm and supported at each end will present a ratio of 4:1. That is, 600Kg at 800mm will cause a force of 120Kg at the long end and 480Kg at the short end. What that means for us is the use of a length of wood or metal on a pivot at one end, the weight of the cars wheel at the 800mm point will be easily measured with a 0-120kg bathroom scale at the other.
Take the measurement presented on the bathroom scales and multiply it by 5. This gives the true mass on the beam.
This can be scaled up for heavier cars, but the ratio does change. A 1200mm long beam with the load at the 1000mm point will require a ratio of roughly 6:1. That is, 100Kg on the scales will reveal a 600Kg point load at the 1m mark. It’s important with spring type scales to keep the weight at around the mid point of the total range as this is where they are at their most accurate.
Now, we have always made a conscience decision to not cover drag racing here at Race Magazine. Not because we don’t have any respect for it, nor because we don’t recognise it in some way, but because it’s so widely covered. Covered to the point that it as a sport drowns out most other forms of grass roots racing.
Having said that, I feel the need to share a story with you. It is a story of internet challenges, no money, duct tape and a general lack of any sense of self respect. I feel I should point that last part out as the base car was yet another VN commodore. Poor life choices etc.
There are some things that Australian event organisers and venue owners should take note of that the drag racing fraternity have enjoyed for many years. The main one being ease of accessibility compared with CAMS events. Generally, to run at a circuit or hillclimb at the most accessible club level, you need club membership, a racing licence, a car that will survive a CAMS scrutineer nit-pick, and either a day off work or wait for the weekend. Not so with the most accessible form of drag racing. Any given Wednesday night you can front up to Western Sydney Motorsport Park, pay your money, go through a quick safety scrutineering and then go line up for a run. At the end of each run you stop at the drive through window and get the result on a slip of paper. It is simple, easy, reasonably cheap and even the most under-funded motor sport enthusiast can have a go.
And have a go we did.
Found this Driveshaft Angle and Phasing Demonstration on youtube a while ago. Here is an excellent demonstration of the problems that are associated with universal (or Cardan) joint, and the importance of choosing your angles and phasing very carefully.
Thinking of putting a carby on an LS1? Better read on before you do!
Hot Rod magazine in the USA recently did a comparison between 20 LS1 style inlet manifolds, producing some very interesting results.
The article can be found here: http://www.hotrod.com/features/1507-20-ls1-intake-manifolds-tested/
They published the data and findings on their website, but there wasn’t a lot of deep comparison analysis. We took it upon ourselves to cut and paste it into Excel and research their findings a bit further.
The LS series of engines has become an automotive phenomenon due to their high output to mass ratio, the cheap and common aspect due to the sheer volume that has been manufactured and sold across a simply ridiculous range of vehicles. Everything from medium sized sedans to vans and trucks.
They are a very robust engine too; able to develop decent power on stock internals and they run a hackable, tuneable Delco ECU. Overall they are a package that is hard to beat. The net result is the damn things get put into pretty much any platform you can think of (including Porsche 911’s and aircraft).
Hot Rod Magazine in the US has done it again.
They tested 20 inlet manifolds to suit the popular LS1 style engines. While this might seem like a clear cut exercise, the results are fascinating.
There are some things to bear in mind however. The test engine is far from stock (a cammed iron block 6.0L LSX), and that peak power is less important to those of us that need lots of torque and a good spread of power to get around a tight circuit, compared to the drag racing fraternity.
Another point to remember is American horses seem to be much smaller than Australian ones, and therefore more fit into a smaller area than they do here. The US seems to consistently yield higher dyno readings than our local ones.
They tested some of the original equipment fitted manifolds from various models as well as a bunch of aftermarket gear.
Way back in issues 1 and 2, this article helped shape the future for the magazine as a technical resource for grass roots motor sport participants. It is still relevant today, though there are now newer tools and methods of thread repair available to the home user.
We have all done it; any of us that have ever picked up a spanner and tried to work on these infernal contraptions of ours. Often it happens at the start of a job, that last manifold bolt we leave because it looks rustier or more difficult to get to than all the rest. Usually though, it’s the last bolt on the job we have left to tighten before we can kick it in the guts and revel in our technical brilliance. It starts with that horrible sinking feeling in the pit of your stomach as the bolt tightens then goes slack again. It ends in a string of curse words that fly across the engine bay milliseconds before being followed by a spanner and half a bolt.
Australia was the first in the world in 1979 in one aspect of motorsport technology – the televised in car camera footage. Back then one Peter Williamson in a Toyota Celica was willing to carry the 70kg (yes really 70kg) of camera, battery and transmitting equipment around in his car. Of course all the fast runners with a chance of winning were NEVER going to accept the weight penalty for some TV coverage … my how times have changed!
Here’s something interesting that we came across the other day. A company in Leesburg, Virginia called Piper Motorsport are installing a mid 80’s Mercedes-Benz 190E body on a late model C63 AMG platform. As yet, we have no idea if it is to be a dedicated racing car, or just a cool streeter
[sam_ad id=”1″ codes=”true”]