Even in the 80's was real turbo lag. I had 2 Daytona Turbos. Imagine being at 2000 RPMs and punching it. Wait for it, wait for it, cross 2500 RPM and bang, off it goes. Nothing at all below 2500. Even punching it above 2500 took about 1-2 full seconds before full boost. My Z4 35i is worlds ahead of that with decent power by 1800 RPM and maybe 1/2 second to full boost at worst. Most N/A cars don't have that response down low. It's only a lag compared to the best cars. My '02 M5 could rock your head back and forth in sync with punching the throttle from 2000 RPM up.

Of course the X5 weighs 1500 lbs heavier and has the extra weight to get moving. Plus I definitely had auto transmission lag in my '08 550i. DS or manual mode cured that. I'd suspect the Diesel still with the 6sp auto would be the same.

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Richard
Sir Snaps-a-lot, 9 Time Dragon Slayer (54 runs!)
2011 X5 50i Alpine White, Biege Nappa /Lt Poplar M Sport
2009 Z4 35i, Black Sapphire/Ivory-Black/Anthracite

Gone but not forgotten: '08 550i, '06 X3, '06 650i, '02 M5, '99 540i