steveng37

I currently have the motordyne resonated xyz pipe paired with the top speed y back on my AWD sedan.

I am seeking to replace the cats and be done with the exhaust. From what I seen, whatever i replace my cats with should be resonated.

Here are two options I was looking at:

1.) Adding FI RHFC ($700ish shipped).
2.) Adding FI RTP + HFC module for the XYZ pipe (around 500 or so with used parts)

Option 1 seems to be fool proof, as there would be a total of 5 resonators in the setup: 2 on the cats, 1 on the y pipe, 2 on the midpipe. Seems like there wouldn't be any issues with rasp.

Option 2 sounds interesting, but I would be removing the resonator on the y pipe, thus having 4 resonators. This seems like it can have uncertain results because i am losing 1 resonator, but adding RTPs. Keep in mind, the XYZ pipe is a 3" outlet going into the top speed mid pipe. The whole point of the resonator on the y pipe was to help tame some drone / rasp from the 3" outlet. So overall I think option 2 has the risk of rasp / drone.

Chime in and let me know your thoughts/ideas

Rochester

iTrader: (9)

I think a loud exhaust is best when heavily resonated. It takes the edge off from what is otherwise an awesome sound, but actually hard to live with... if that makes any sense. It's that thinking that makes me aspire to the Jaguar's active exhaust, where the driver can choose between something awesome, or dial it up to full-throated nasty, and then back down again with a flip of a switch.

So let's take that analogy into your current project, assuming you're already happy with your exhaust, so that whatever you're doing here is only going to make it better. In other words, there's no bad choice, just two good ones. Where current state is "good", and your go-forward options are 1) "great" and 2) "awesome". You don't really know if option 2 is awesome, but you're thinking it could be. But the real problem with option 2 is you have a higher risk of discontent than is possible with option 1.

My advice: only do what you think you can live with all the time, irrespective of how awesome it might seem in the moment. I think that's good advice for any car mod. Particularly a daily driver, which is what I'm guessing when you say "done with the exhaust".

However, if the car is a toy,.. every option is on the table, all the time.

projectpanda13

iTrader: (2)

I agree with Rochester. Its the more cost effective option with least risk. There's also a set for sale on facebook if you're on there.

$350 guy is in NYC

https://www.facebook.com/photo.php?f...QpHfYbzAQUCUoV

Dzionassi

Why would you want to remove resonator from y pipe, keep it.
If smell is not bothering you go with TP. I have total 6 perforated resonators, 2 cats, 2 multi-chamber Helmholtz and 2 mufflers LOL

steveng37

I went with option 1. Picked up some FI RHFC only used about 1500 miles, for a very great price. Ordered z1 metal gaskets.. Can't wait to have them installed!

Rochester

iTrader: (9)

If you're in for the long haul with this exhaust, consider swapping in SS nuts and bolts.

Also, the FI cats don't support the OEM cross-member, so you have to do without, or come up with your own solution.

Dzionassi

Stainless steel bolts will get loose over time. As good as it sounds in is not good solution for exhaust.

Rochester

iTrader: (9)

I only used SS on the catback, not the cats. I've checked a few times over the years and they're still tight, no rust, so...

Then again, maybe after all this time they won't come off even if I wanted them to. IDK, not an engineer.

Dzionassi

SS nuts and bolts? Interesting, I always have problem with SS where heat is present...