I have narrowed my exhaust search down to this one. They are out of stock until mid may. That gives me some time to ask a question and make a decision. I have not found any threads that talk specifically about this.

Purely by opinion, I want to know what gives better sound. The 2.5" or 3"? Some say 3 is the best sounding no rasp. Others say the 3 has rasp and the 2.5 is the way to go.

I would love to hear a clip of the 2.5 and 3 on the same car to really hear the difference.

I know people say on N/A the 2.5 is the way to go. On the same note I wouldn't get the 3" Y pipe but go with the 2.5 so it wouldn't be a true 3" on an N/A.

I just want to be happy with the purchase and not end up selling it a few months later.

Thanks for the help.

 

Dude you can order RSR instead of TOPSPEED if TOPSPEED is out. RSR is actually the authenticator exhaust and TOPSPEED is its exact replica except its polished. I was going to get TOPSPEED too but they kept extending the date of arrival on their exhausts. So it may be a long time till they get them in.

You can pick up RSR Exhaust for $699 plus shipping from HOPUP RACING. Send them a PM.

 

And yes, get the 2.5 piping if you are N/A. You would be happy with it.

 

The change from 2.5 to 3 inches at the Y might lose some exhaust velocity/bottom end tq. I would just run the 2.5 if it were me, unless I had some FI plans in the future. Here is my other concern regarding the 2.5-3 inch switch at the y. When they make performance exhaust systems, they try to make the path the exhaust takes as smooth as possible, right down to the way they bend the pipes, same with intakes. A half inch change in the middle of the system would disrupt this "smoothness" and create some turbulance in addition to losing some pressure. Those are my thoughts on that anyway. What are the performance gains for this exhaust? I'll do some searching. Being a Y back exhaust system, I'm curious.

 

Okay so 2.5" is the way to go. It does make sense getting the piping all the same size. I figure better ask to be safe. I honestly can't say what the dyno is on this exhaust because I have never seen one. I have searched but haven't seen a post for it. Doesn't mean there isn't one out there though. I just love the way it gives off that exotic sound.

RSR would be nice but I can get a brand new topspeed for 450.00 shipped. If there is an RSR that could match that it wouldn't sound like a bad idea. I don't mind waiting a few more weeks though.

 

I Have A Topspeed Pro1 On My Car Great Sound I Love It Not To Loud Not To Quiet I Noticed A Good Increase Hp On Top-end!!!

 

Here is a link to the RSR exhaust dyno and Y pipe on 2007 Z (HR MOTOR)

https://my350z.com/forum/vq35hr/351109-finally-got-around-to-scanning-my-dyno-sheet.html

He claimed to produce 277 HP and 244 TQ

 

Those are some nice numbers on the dyno, thanks for posting that.

 

You are welcome.