Hey guys, I did some searching and wasn't able to find the answer to my question. Has anyone used test pipes and then after the Y-pipe put in a single HFC? I still need to pass emissions, but a pair of cats are quite pricey. I can weld just fine so that's not an issue, it's more of has anyone done this before. Thanks!

 

The only thing I've read on the forum that does what you are trying to do is Motordyne's XYZ y-pipe. It has 3 different modules that attach after the merge: a straight extension, a resonator module and a HFC module. It's not cheap though but will achieve what you are trying to do.

 

Honestly though, considering it's motordyne, the price will probably come out the same to getting a regular y pipe and HFCs

 

You'll likely run into restriction problems on a single, not to mention there isn't a good place to put it unless you go all the way back where the OEM resonator normally sits.

 

Tony's done a lot of testing and research to create the XYZ system as he does designing all of his products and I seem to remember the XYZ with all 3 modules makes a bit more power than a stock system so I would assume his set up isn't causing a restriction..

 

Thanks for the responses guys. I hadn't even looked to see that he had made what I was thinking of. Since a set of HFC run around 500 for berk, I was trying to get something similar for less money. I wanted to use resonated test pipes with a 3" exit out of the Y-pipe into a single HFC. I looked at the price of his pipe and that would be cheaper then what I've found, aside from making my own.

 

If you just use a regular Y pipe (use same diameter as XYZ pipe) and a HFC with the specs of at least " 4 inch metal substrate High Flow Catalytic converter (HFC) @ 200 CPI, 3" inlet / outlet"



you shouldn't run into any issues. It probably won't be quite as good as the motordyne piece power/sound wise but it would be cheaper and perfectly good if you're not trying to build a ballermobile.

 

I don't think I've heard a single setup with Berk HFCs that DOESN'T sound like a fartcan. IMO stay away from Berk, you can get the same performance/quality for less like from Z1 or Kinetix.

 

Lol while I'd love a ballermobile, better than stock is about what I can afford haha. Thanks for the input, I shall find a nice large HFC as it's way closer to cheap

 

Agree AND a lot of posts on here discussing issues the Berks have including many that mention failure at very low miles.

 

Yeah that's using a 4" HFC though.

 

I’m in this situation now, and trying to decide where to place the HFC because I want to run ART pipes.

I called Tony at Motordyne and asked him what he thought, he mentioned buying two 3” magnaflow HFC’s and welding some v bands to them, place in place of the G extensions AFTER the mid pipe resonator.

Tony said you need to keep an eye on AFR when placing HFC’s in supercharged setups, as in some independent testing the stillen supercharger made less tq with test pipes than it did with OEM cats 😅. I need to figure out where to place a wideband sensor!

magnaflow 3” are approx 9” long, but clearly almost 1/2” could be cut off both ends and welded v bands to. https://www.ebay.com/itm/17111164765...mis&media=COPY

this china branded 3” is said to be 400 cell.. (I doubt it’s truly 400 cell), only 8.5” long; which is almost exact length of G extensions. https://www.ebay.com/itm/37378430141...mis&media=COPY

 

I've seen HFC's mounted completely at the rear, basically mounted where the mufflers would usually be. It's not a bad location too since there's a lot of room and plenty of factory installed heat shielding. These cars didn't use a muffler though, resonator and HFC only.

The only downside would be routing the wiring for your downstream sensors, I'd pull it back up into the cabin, route through the interior to the trunk, then dive down to the underside of the car. I don't know if it would affect tuning out efficiency codes (I doubt it) but maybe @seymore4 could shed some light on if there's any issues with that far of a distance between upstream and downstream sensors.

 

As long as the downstream sensors are after the cat should be fine

 

I planned to keep the downstream sensors in the art pipes, do you think that will cause codes because of the downstream restriction?