This year, the IndyCar rules committee will allow three turbocharger sizes, depending on the Indy race course: large oval tracks will be permitted to boost the air induction pressure to 1.3 Bar; smaller ovals will top out 1.4; and road courses will reach 1.55. The 1.3-Bar turbocharger boosts the engine's horsepower to about 550 HP, while the 1.55-version stretches the horsepower to about 700 HP. http://www.edn.com/electronics-news/...a-700-HP-punch
If 1.3 gives you 550, 1.55 gives you 700, the 1.4 gives you 610. Another article said they wer 70 hp down at Indy this year which put the engines at 620 last year. With only slightly less hp on the short tracks, this car should have been faster with all it's advantages. The fact that it was slower at Milwaukee shows it handling is still not that good.