i just wanted to know if the test pipe from rrm is worth it or not, and also why cant i use it on highway?

 

It's ILLEGAL for on road use. Many people will say yes, very few will say no. Personally I think a high flow cat is better (RRM doesn't offer one at present though), but if I were running a test pipe right now I'd probably have set the rear half of my car on fire already. I'm going to move this to the newbie forum because reading or searching could easily have netted you an answer.

 

The reason you cannot use it on the highway is because it elimates the most crictical part of you emission control stuff, your cat.

i would also recommend you go with a high flow cat.

 

The test pipe makes a world of difference in gains by getting rid of the 2nd cat, but it has two downsides:
1. It's stinky and illegal.
2. It makes the pitch of your exhaust note a tad higher.

I was more than pleased with my test pipe and the only reason I sold it was cuz the gains on my header were better and I had to choose between the two to save myself from sounding like a fartmobile. I'll be going with a highflow cat in the near future as well.