BRUTALLY HONEST dyno check, How Much Power Does Bootmod3 Stage 2+ Tune ACTUALLY make! 

I'm sure it's your fuel quality and the temps. Oil change and some good tyres should improve your times. If you can't trust the dyno then trust your times. I'm running stage 2 however here pump fuel is 91 Oct. / 95 ron and I can definitely feel the difference in power. Although I haven't dyno'd. I'm wanting to try e50 and wider tyres 255. Future mods is an lsd and hybrid turbo which I've heard improves things on pump fuel. I'm also at altitude so doesn't help.

You need to change the spark plugs to step colder

Akrapovic DP is 300cel, you would get more HP with less restrictive DP, like 200cell or 100cell or decat (don't do that:P). With 300cel smell is not existing. With 200 cell you will get some smell especially when you maneuver in undeground garage. After getting out of the car, you will smell that smell.

I know all Dyno read different, dragy always a good measure of power. Have you done any 100-200kph ? Here in UK l will probably tune my car using morebhp custom map stage 1 gives 8.1 100-200 with around 440 hp at the crank. Seen 3.8 sec 0-60 and 11.9@120 mph 1/4 mile but lower da also helps in the UK. Great content on the 140.

Please don’t compare power figures to American dyno numbers, like the calories in their food, they are always over inflated.