The all important question....How much power does it make?
So I have a rare Thursday booked off work... Christ its 9am and I am bored already. A quick message to a friend in the industry, Jack at J's Garage and I was off to Attleborough for some time on the dyno, driving lots of different high powered cars regularly can make you lose your sensation of speed so lets put a figure on all of this tuning.
After a rather wet drive there and still using the original primacy tyres I was suffering with a lot of wheel spin initially but after getting the straps pulled down really tight and getting some heat in the tyres we managed to get it to hold onto the dyno until I started pushing the torque north of 300ftlbs where it was just too much for the primacies and I couldn't get a full run in 5th without some wheel spin but the figures coming out I was more than happy!
Ignore the fact it says impreza, Jack thinks he is a bit of a comedian! At 1.3 bar of boost with no methanol and soft ignition timing what I call my "daily driver" map we saw a lovely flat torque curve over 300ftlbs and 398bhp pretty much double the stock cars torque and power output right off the bat, lovely! Once I turned the boost up to 1.4bar and added the methanol and much more aggressive ignition timing we saw a whopping 460bhp and 400ftlbs with wheel spin(you can see the graph stops at 7200rpm when I am actually revving to 7600rpm which can be seen on the lower powered run. One of the major downsides to a dyno you can't always match the load to the real world where I can see 1.5-1.6bar of boost on the road with the internal wastegate maxed out on the dyno I could only achieve 1.4bar so I am confident with the real boost being achieved and some grippy tyres we are more likely in the 500bhp 450ftlb area. I will be back with some grippier tyres and a turbosmart dual port actuator so I can force the boost to 1.5-1.6bar on the dyno and get that 500bhp graph!
All in all I am very very happy, not bad for a daily driver with fantastic reliability on an almost stock engine with only the weak links removed(poor oiling and weak conrods) proof you don't need all the hassle and extra expense of forged pistons for sub 500bhp. On the road its amazing to drive, very little turbo lag when you consider the standard cars peak torque is exceed after only 3200rpm......what torque dip?!?!
Despite various GT86 owners thinking I am mad it is also very controllable even with the factory tyres that have a terrible reputation for grip it is not lighting the traction control up in 3rd onwards in the dry on the lower powered map, the standard suspension still soaks up the bumps well and allows some squat on the rear under power, the upgraded discs and pads on the stock callipers I find ample and we have lots of options available : https://www.fensport.co.uk/collections/toyota-gt86-2012-to-2016/category_braking
I am not saying it would be a track warrior in this setup but its huge fun to drive and can show a clean pair of heels to lots of things on the straights!