I'm a horsepower junkie. Give me any car and I can squeeze more power out of it, whether it be Yugo or a Daihatsu; it doesn't matter. So when a buddy of mine purchased an MR2 turbo, I was the first person on his list to call for help. Being a purveyor of MR2 turbos, it was good to know a close friend of mine was joining the club. The Toyota was equipped with a brand-new, fully built engine, CT26 upgraded turbo by Turbonetics, HKS VPC & GCC, Blitz Dual SBC Spec-R boost controller, Blitz Nur-Spec exhaust, Blitz downpipe and GReddy intercooler.
Since the engine was brand-new, my friend performed the proper 1,500-mile break-in to seal the rings of the pistons. Once the break-in was done, it was off to the dyno. On its initial run, the MR2 mustered 168.7 hp and 165.9 lb-ft of torque to the wheels at 0.43 bar (6.32 psi) of boost.
However, the 3SGTE engine was having trouble revving past 6000 rpm. After examining the dyno graph, we diagnosed the problem. The Dynojet chassis dyno we used had an air/fuel ratio monitor option, so we could see the MR2 was running extremely rich at the top end (5500 rpm and up).
A few clicks of the HKS VPC and GCC and the rollers turned. This time, the horsepower rose to 179.1 with 166.1 lb-ft of torque at the same boost pressure (6.32 psi). This time around, the 3SGTE engine was able to rev to the factory redline of 7200 rpm. After we checked the air/fuel reading, the Toyota ran in a more optimum range of air/fuel mixture but remained rich at 6500 rpm. After making some more key tuning adjustments on the VPC and GCC, it was back to spinning the rollers. This time, the peak output rose to 188.7 hp and 172.1 lb-ft of torque-an improvement of 20.0 hp from the baseline run! More importantly, we were able to increase the output at 7000 rpm by 33.5 hp at the same boost pressure.
Without a chassis dyno, we would have never been able to extract the additional power from the MR2. The HKS VPC and GCC are tried-and-proven veterans of modern turbo performance. And as illustrated here, this tag team is still a relevant and potent avenue of tuning.