My first observation after removing the stock intakes and cleaning them up was that, when matched with the carb spacer, there was quite a lot of room to open up the intakes to match the spacer. I gained at least a 1/4" of overall dia. on avg. and cleaned up the flow substantially in my opinion. When checking the spacer against the head, the primary side matched almost perfectly but the larger secondary opening will require some additional porting on the head to be perfect. So in addition to added torque or hp, the spacer makes for a great tool to match the intakes to the head.As for performance, I recently switched from a not so well maintained o-ring chain to a fresh standard chain and noticed a lot more improvement with that change than with the carb spacer. The spacer just seemed to make the engine run better at lower power settings so probably enhanced the torque more than anything. I'd recommend it if you have the spare change, time and ability to do some basic porting work. If you don't plan on matching the ports during the swap, I wouldn't bother with wasting your time or money on the spacer.