[KTL]

From my experience with the two, the shorty type fit more like a SSI or Georges would fit. So you don't run into interference with other things under the car, nor at the lower valve covers. On the longer ones I had, the flat, forward laying pipe contacted the main oil supply tube beneath the engine oil cooler. Was not happy with that...... I think the valve cover fitment was tight with the longer ones? After thinking it through a bit, I do recall now that OBX makes both types- short and long.

Also, if I recall correctly, both of those headers allow for you to use the factory SC/Carrera oil scavenge line that runs along the back of the engine and then in the passenger wheel well to the external thermostat. Point being is you don't have to switch to the SSI/early oil line that is crescent-shaped and runs underneath the engine-trans mating point.

Let's just say that with both headers shown you get what you pay for. Do a search and you can find people's experiences. I had the OBX for a year before I de-modified the car to sell it. Worked fine and fit pretty good. Did I expect a huge increase from them? Nope. My intent was to take advantage of weight savings in losing the factory heat exchangers. OBX shorty setup with the muffler extensions and M&K shorty soda cans did the trick. Power gains were undetectable from the butt and I never bothered to dyno it. Didn't care as I was just doing lapping days with the car.