LOTUS INDYCAR ENGINE
marque on the finer aspects of its desired engine design, Judd says Lotus allowed the Rugby-based firm to arrive at the DC’s final specifications on its own. ‘They left us pretty much to do it,’ said the veteran F1 and Sportscar engine designer. ‘Their brief was to produce an engine to apply to the rules. We did the best we could based to a reasonable extent on stuff we’ve done previously because the time was fairly short. So we discussed various concepts with them and showed the layouts as we were going along, but they basically allowed us to use our initiative pretty well.’ Judd’s previous turbocharged
Indy car experience came during the 1980s in CART with its 2.65-litre Brabham-Honda V8, and again in the 1990s when its V8 was quietly utilised by Toyota when fitment issues arose with the Japanese marque’s first CART engine.
SIGNIFICANT ADVANCES But there have been significant advances in engineering design made since then and, for the 2012 engine, Judd was keen to use them: ‘We did the modelling and design with SolidWorks, and all the programmes that go with that,’ he explained. ‘We worked with Dallara on the modelling of the ducts to feed air to and from the turbos. That’s a bit of an interface thing, really, the feed to the turbocharger, that duct is a Dallara part. And in turn, the turbocharger to the engine, that’s a Lotus part. But we actually got Dallara to run a fairly basic closed simulation using the simple thing that comes pre- packaged from SolidWorks. And then we did it in more detail with Dallara throughout.’ If there was a benefit to
Lotus’ late start, it came in the form of the reduction in engine capacity from the original 2.4 litres to 2.2 litres in January, 2011. While Honda had already built a bespoke 2.4-litre unit by that point, EDL was able to start on a smaller capacity unit from the outset. And with many of the final engine regulations by then in place, including a 12,000rpm rev limit, Judd was able to assess the areas of interest to focus on: ‘You need to maximise airflow
18
www.racecar-engineering.com • May 2012
Lotus’ two rivals in the series are both big guns, with major manufacturer backing – Chevrolet’s twin-turbo V6 (above) is built by Ilmor, while Honda Performance Development’s version (below) is another single turbo unit
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100