Dyno Day

Oil Pan Plug

I went in to Behe Performance for a track-day inspection. I got that, but I also got a couple of surprises — one pleasant and one expensive. I knew my car was leaking oil. You could see it dripping at the drain plug. But it turns out the pan seal was going bad and the drain plug was almost stripped. In the photo you can see how two of six threads are already gone. So rather than losing all of my oil on the track at Summit Point this weekend, I went ahead and had the pan replaced. That’s the expensive part. Now the pleasant part.

Behe has a new Dynapack dyno. John suggested we should hook my car up to the dyno to see what potential there might be for doing some dyno tuning. From the factory, my car came with 163 horsepower (at the crank) and 155 ft-lb of torque. If you assume a 10% drive-line loss in horsepower, that should translate to about 148 hp at the wheels. I have done the typical bolt-on mods of pulley, intake, exhaust, hotter coil, cooler plugs, and uprated plug wires. On the engine management side, I also have a canned tune from MTH. We were expecting something around 180 to 185 hp.

Much to my surprise (and I think John’s as well) it was pulling 188.8 hp at 6900 RPM. Max torque was 165.9 ft-lb at 4250 RPM. Considering those numbers were at the wheels, that’s about 207 hp and 188 ft-lb of torque at the crank. Chart below. Not bad when you consider the cost of those mods adds up to only about $1,500.

dyno plot

As for DMH, John also had their Cooper S test car which he let me drive. This beast has a re-worked head and cam as well as extensive tuning from John. It’s pulling over 240 hp at the wheels and a max of 190 ft-lb of torque. It revs all the way up to 8,000 RPM. When I was driving it, John kept telling me to stick my foot in it and stop driving like a granny because I was shifting short at 7,200 RPM. It was almost too much power for a street car, but I can only imagine what it must be like on the track. It was quite impressive.

I’ll go back to get some more dyno-tuning in the future. I’m not sure John can get much more horsepower out (short of raising the rev limiter some more), but he thinks he can get me 170 ft-lb of torque at the top end (6900 RPM is only 143 ft-lb now.)