The broader & extra torque the 135i makes will jump the M3 off the hit. The M3 will eventually catch up, but it'll take a while, and the extra HP will only become evident in the higher gears. The 135i is no slouch.
You all know my favorite saying, HP sells cars, torque wins races, and this is a prime example of a torquier power characteristics winning over a much larger HP advantage of the M3.
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LS7 427CI w/ECS Novi 2000 : Caravaggio Widebody and Full Leather & Alcantra Interior
903rwhp/815rwtq : 10.3@152mph