As we move ever further along the road of increasing the efficiency of race engines and drivetrains, we will see energy recovery play a more important part. Turbo-compounding, where energy is recovered from the exhaust flow, remains strictly for commercial vehicles for the time being. However, regenerative braking is very much a current technology, both for roadcars and in racing. With Williams, Flybrid and Zytek active in sportscar racing, and the Formula One engine manufacturers running KERS this season, energy Read more…
Archive for July, 2011
Electric motors
Monday, July 4th, 2011Drilling could be cool
Monday, July 4th, 2011
In response to my earlier articles on cylinder head cooling, two comments were posted on the website by readers. Both are written more or less from the perspective of current cylinder head material and its limitations, providing enough food for thought on alternative concepts. The major driver is to achieve sufficient cooling for the several components in the cylinder head, preferably in combination with a simple and lightweight design. Read more…
The return of Viscosity Index
Monday, July 4th, 2011
At the time of writing, with two high-speed superspeedway events under their belts, oil formulators for NASCAR are at last breathing a sigh of relief. Since the fuel for this year has been revised to include 15% ethanol, subsequent post-race engine oil analysis has shown that there is no unexpected deterioration, and piston wear - although higher for the high-speed plate engine tracks - is no more than expected. But if we are honest, that was only of passing interest. With many events around the world using similar blends, the effects of ethanol on high-performance engines is now well Read more…
Nuts: design for increased fatigue resistance
Monday, July 4th, 2011
Nuts are often given little consideration in design, especially compared to the stud onto which they engage. The reason is quite simple: nuts rarely fail unless they are completely unsuitable for the job. What is less commonly understood though is the fact that the nut design can have a critical effect on the fatigue resistance of the stud onto which it fits and the pre-load in which it is responsible for, in cases where stud failure coincides with the first loaded threads in the nut. Read more…
Le Mans exhaust systems
Monday, July 4th, 2011
Race engine exhausts are expected to do a tough job without suffering failure, a job they generally do very well. The results of a broken pipe can be very noticeable for two main reasons - loss of performance and a marked increase in the amount of noise generated, especially on silenced systems where the breakage is upstream of the silencer. With a premium placed on both reliability and system mass, many race exhausts therefore use titanium, stainless steel and Inconel materials. Read more…
It’s all in the timing
Monday, July 4th, 2011
I have to admit that despite my fascination with modern technologies, the art of being a racing driver was always encompassed in the skill of changing gear - the crispness of the up change and the shear poetry of it while simultaneously braking and changing down. Judging it to perfection was satisfaction indeed, and many more hours were spent practising either on the road to and from my place of work or in the ‘cockpit’ of an armchair at home. Read more…
Weighty matters
Monday, July 4th, 2011
In these financially straitened times, the fuel consumption of engines has taken on a new level of importance - not, I hasten to add, to minimise the production of carbon dioxide and its environmental impact on the world but, within motorsport, the simple realisation that every unnecessary litre of fuel weighing 0.75 kg, is 0.75 kg too much. Irrespective of the current financial climate therefore, minimising fuel usage seems to make so much more sense. That being the case, in any engine test cell, the fuel flow meter is now a thing Read more…
Modern crankshaft machining methods
Monday, July 4th, 2011
The manufacture of crankshafts is not a straightforward matter; many pitfalls await the adventurous novice attempting to make his own crankshaft, and there are reasons why there are so few reputable race crankshaft manufacturers.
The general trend for trying to reduce engine friction means that modern design practice is often in the direction of reducing bearing diameters. This means greater care needs to be taken in manufacture, Read more…
Thrust-face design and finishing
Monday, July 4th, 2011
The forces acting on the con rod are considerable, and the components to which they are attached are surprisingly flexible, although they may not appear so when you pick up a component such as crankshaft. The deflections of the crankshaft (bending and torsion) and the con rod (torsion) give rise to a tendency for there to be some axial force on the con rod trying to force it one way or the other parallel to the crankshaft axis. Read more…
Bearing coatings
Monday, July 4th, 2011
The preponderance of multi-cylinder four-stroke race engines means that the production and supply of bearing shells is big business. The share of the bearing market occupied by two-stroke and four-stroke engines with assembled crankshafts that use rolling-element main and crankpin bearings, or four-stroke engines that are designed to use special rolling-element bearings with split outer races, is very small indeed. Read more…
