There is no exact proof in any of these online claims that broken cat material gets sucked back into the exhaust ports, from a reputable source.

Most of these claims are other online forums or ask the mechanic sites etc.

Resonators create no exhaust gas restrictions, cats do... HFCs paired with resonated or non-resonated exhausts will produce the same gains. Regular cats vs HFCs do change the restriction however. This has been tested by lots of different exhaust manufacturers.

+1 Happened to a friend of mines spec-v last year

Isn't a little bit of exhaust sucked back in as some sort of EGR? I read somewhere Nissan uses that technology but not very sure

Nissan dealers have been known to hire people. People post things on the Internet. People are highly unreliable.

Would love to see picture of said Berk cat. Evidence that cat material was found in combustion chamber or oil pan. Maintenance records of said 370z with accounting of people who did the work. Frequency and type of oil used. What kind of oil filters used for all oil changes. Any monkeying around with tune?

Yes some other motors have had issues with precats but haven't seen much evidence to regular cats located a ways down the system causing this on a VQ37. Not saying it can't happen but would like to see real evidence.

Otherwise this is just a bunch of pointless yapping and sensless product bashing.

One vote for stock cats and peace of mind.

Just get LTH's and then you can't have a problem with the cats. That's got my vote.

I know this can and has been an issue for pre-cats. How ever this is just impossible for a normal Cat. Yes there is some gas sucked back during overlap but you have 5 other cylinders one of which will be exhausting completely. So at most the exhaust pressure would be reduced but as for an over all back flow of the exhaust is just BS.

Your blown engine was due to other issues, the destroyed cat is unrelated. And more then likely all the oil burning clogged the cat up and exhaust pressure just ripped through the clog. But all this is difficult to prove hence why they are just replacing the engine.

Isn't piping separate to the cat, with each cat seeing three cylinders?

You're lucky he DIDN'T give you a "for sure answer". Shuffle back to the lobby and zip the lip, you just got a free engine even though the crap parts from Berk are what destroyed it. Go play the lotto.

:iagree:

Until someone tears the engine down. You will never know what really happened the this engine! Talk all you want about it. It's all guessing for now. :shakes head:

This is the only scenario which makes any damn sense at all.

Unless you go with test pipes, there are examples of all types and brands of catalytic converters failing, stock or not. In my opinion, the vast majority (myself included) have had nothing but great experiences with Berk HFCs.