I installed Mac long tubes and the O/R Prochamber this weekend. I was first impressed with the fit and finish. The install took 3 hours (but I have a hoist) and there are no clearance, rubbing or rattling issues. I did not do a before and after dyno pull the same day, I should have. The last time I had the car on the dyno was last January. According to my records, the day I did the dyno pull it was 28 degrees out and the humidity was 22%. This weekend it was 62 degrees and the humidity was 94%. That being said, I picked up 11 RWHP. According to my HP Calculator, the difference in humidity would account for a 4.9% HP loss. The HP gain is probably much greater.
The improved sound alone is worth the price.
The improved sound alone is worth the price.