So I'm stuck in a odd spot right now, my OEM Cat has blown up, and I'm stuck with the choice of either getting a Berks HFC or get a used OEM cat. I do eventually want to get a new exhaust other than OEM, probably 70mm though I'm not dead set on anything yet, that would be a few months down the line.

My question basically is, would it be better to get a cheaper OEM Cat and then do the upgrades such as a HFC and a new exhaust later, or to just get the 70 mm HFC and then later upgrade my exhaust?

Test pipe is not an option.

 

Save time and money and just get the hfc

 

Interesting, I just installed my Berk 70mm HFC a few hours ago...no smell, no CEL, no whatsoever. I love the sound of it.

Depends on which state you live in. Some states require a cat to pass smog, some don't. I would personally get an OEM cat first and then Berk HFC later if I decided to upgrade my exhaust...

If your state doesn't care about having a cat, I would just go for the Berk right away.

 

you want to maintain the same or as close to the same diameter throughout... if you are keeping stock exhaust, id look for a 60mm or 63.5mm HFC. or find a used OEM one. I wouldnt get 70mm test pipe or HFC until you changed your exhaust to a 70mm.

 

Are there any real benefits to getting the Berk HFC? I've done lots of research and can't find any before and after dynos of the berk HFC compared to stock cat.

All the dynos Ive seen have added either a tune, header or exhaust, or a combo of them, with the Berk HFC, and then compared it to stock. I want to see a direct comparison of only the HFC changed out vs stock cat.

I want to keep stock header and stock catback exhaust, and I only want to change the cat to the Berk HFC. Wondering if it's worth it and if it actually does anything though.

 

a test pipe or HFC is worth every penny if you have a flashpro or something to tune it. Mostly mid range gains. My car was night and day before and after the FlashPro tune i received from Gernby with my 60mm test pipe. VTEC i believe is around 3800-4000 and redline is 8400 rpm. With a HFC you can still lower VTEC engagement, but not as low with a Test Pipe IIRC. just maintain equal diameter.

 

...and without a tune, a HFC gets you virtually zero gain. The only reason to get one is if you are going to tune (or if you are going with a larger diameter exhaust, and want the cat diameter to match for best system balance, in which case you aren't in need of the HF from your HFC (compared to oem), just more diameter.

Note that its not that the OEM cat (on the S) is restrictive, its that there are resonant harmonics that do not allow lowering VTEC much, without a power loss.

When they lowered redline on 2.2, the VTEC powerband shrunk considerably. Why didn't Honda just lower VTEC rpm to retain the same powerband? Because they couldn't without redesigning the cat, and maybe it wouldn't even be possible to still meet emissions targets and required room for error if they tried.

 

I have a berk 63.5 hfc paired with the uk mod and it performs quite well and sounds good.
I do also have a flashpro and gernby etune...

 

^This. If your plan to upgrade is still a long time away, go with the OEM cat.

 

First off, have you priced out each? Here in CA where a Berk HFC doesn't meet CARB, used OEM cats in decent condition go for more than a new Berk. I'd imagine used OEM would be a bit cheaper in areas with more lax emissions laws.

Also, if you're planning on going with a larger exhaust down the road, you may as well get the larger HFC now. I had a 70mm HFC with stock exhaust and didn't lose power at any point in the rev range on the dyno.