Can anyone share their experience with the FI Resonated Test Pipe as it relates to performance, quality of workmanship, sound, and affects if any on mpg?

My G37 coupe has headers and FI Catback but stock cats, so I am wanting to free up the airflow with the test pipes. I am hoping that the sound is not overly loud and obnoxious, especially at highway cruising speeds and I could get some better mpg.

My G37 is getting 22 - 23 MPG cruising at 70 - 75mph. Some of the bad mpg could be to the previous owner putting on 29lb 20" rims.

If anyone is selling one, I may be interested in purchasing one used if in good condition.

 

22-23 highway mpg isn't bad on this car. I'll preface my comments by saying I do not have these test pipes. But the consensus is that FI materials and craftsnanship are excellent, I've yet to read any comments by anyone to the contrary. Expect the same as the quality on your headers and exhaust. You'll also have a noticeable exhaust smell as well as you are removing the cats from the system.

 

I agree with BB, my MPG is never higher than 18mpg no matter how I drive it. FI quality of craftsmanship is second to none! Also, what brand headers do you have?

 

I believe they are Stillen but I have not had a chance to get under the car to inspect them closely yet. I hope to know that for sure this coming weekend.

 

I love my FI Res test pipes. The in-cabin drone will be worse (not too bad for me), but it will deepen the tone and increase the loudness.

For some reason, when I put the Stillen headers on my car it seemed to drop the drone in the cabin. I'm thinking because it heightened the pitch of the exhaust.

 

I can agree with Staples, I love my FI Res TP too. I get around 19mpg all the time and there is little to no drone, except when it's very cold outside and the car hasn't fully warmed up.

 

holy thread from the dead! ...but yes, FI craftsmanship is def top of the line, and Tony is the man when it comes to customer service!

 

I can tell you for sure from personal experience, header wrap the test pipes it will help with drone and won't decrease the overall volume of the exhaust.