Yeah my top mount is not great in this weather.gettin cooked in there
Top mount? you mean interwarmer? Without injection is no use at all in the summer, even in the winter after a couple of hard runs it's not as efficient!
Front mount all the way and it does make a HUGE difference in the summer compared to the top mount! Saying that hot weather makes my car a bit slower indeed, but not a lot!
Another think standard air intake - relocate the filter in front of the radiator and in the summer (hot days) you can feel cold air coming out of the blowers without the AC, before the relocation it was just hot air all the way, so If I could feel it in the car, I'm sure the engine can feel it as well.
Mind you, my AC does an awesome job, I finally used this year, awesome bit of kit and doesn't use a lot of petrol at all like other cars, I've managed 270 miles before the light started to flash of which 200 motorway in traffic (5 hour drive), 70 miles of hard city driving, and around 100 miles were with the AC on... NOT a bad result in my opinion!