SR20DET Motor Power Gain Port & Polish - Super Street Magazine

People always write to us and ask how much power they can get by building the bottom end on their turbo motors. It saddens us to inform them that they won't gain any power after dropping more than $1,000 to beef up their block. Why? Because forged pistons and rods are just reinforcements. Unless they went with a higher compression piston, they're looking at gains of about zero hp. In fact, most engine builders prefer to use lower compression pistons to work with turbo motors, so they're even looking at a loss in power at times. Doesn't sound like much of a bargain, does it? Well, once they start cranking up the boost and playing with the fuel management they'll thank their lucky stars they don't shoot a rod through the block during a dyno session. But if you're looking for immediate gains, the top end is always the way to go. Depending on the engine type, you can look to steal quite a bit of horsepower from a good port and polish job.

For Yamz' SR20DET motor, he only wanted the best, so we called Darren San Angelo at R&D Dyno Service to get, well, serviced. Yes, it's the same R&D that dynos our cars. Now why would we call a dyno shop to port and polish a head? That's a good question. Probably because R&D's Darren has been building engines since way before Roel discovered the beauty of the cinnamon ring, and he's also responsible for some of the fastest cars on the dragstrip. Porting and polishing is an art, and Darren is an artist. It's much more detailed than having some jackass stand around with a rotary tool and shave away at your head for a few hours. If you get someone who's inexperienced with such a task, you're more than likely to end up losing horsepower. Darren spends a lot of time testing different port sizes and valve angles to ensure that he can maximize the power out of the head. If the gains aren't worth it, he won't even bother-and that's the exact reason why we went with him.