hi all ,
can some one tell me whats the different between :
ceramics HFC , Metallic Substrate HFC's $424.99 & Metallic spun $374.99
(the price`s are from Berk`s)

 

Ceramics can be damaged by unburned fuel and are prone to cracking... and once that happens, it's all downhill. I spent the few extra $$ on metal just to be safe.

 

oh is that so ,,,,thanx its good to know
what about the other two ??
Metallic Substrate HFC's $424.99
Metallic spun $374.99
they look the same in Berk site

 

This might sound bizarre, but I think you should contact Berk Technology and ask them.

 

Metallic Substrate = Metallic HFC, as the core is metallic.

Metallic Spun = Ceramic HFC, with ceramic core and polished exterior.

The chances of cracking an HFC is very slim, even a ceramic. And the chances of cracking the new Berk HFCs with the bracket-tab is even slimmer.

 

Do the chances you give apply also if you have a Nismo Y-pipe?

 

Yes. Unless your car is running abysmally poor, the chances of you cracking an HFC are extremely slim.

 

From what I've read, the main reason people buy the Metallic Substrate ones is because they flow better than the Ceramic. At least that's why I went with the metallic ones - so hopefully those people were right

 

In that same vein if you are NA then the usual statement is ceramic hfc have plenty of flow.

 

For 2007 and up, the Cats flow better than the previous years. Chebosto did a flow bench test and ceramics flow slightly better. Get metallics for the HR, and whatever you want for the DE...

 

well guys
i will get the APS 2.5 dual + Berk HFC Cats , its will be a very good set in flow BUT is it going to be VERY LOUD !!!
i`m an every day user to my z so tooo loud will not work for me
if you have any sound clips for that comb that would help soo much

 

If you want quiet and great gains get: Stillen TD, Borla TD, or Fast Intentions with Ceramic Berk HFCs.

 

My Mangaflow HFC used ceramics, the car ran hot and rich at the track one weekend, rich enough to allow small flame out the tailpipe (oops). That fried my HFC. It broke down the ceramics, and eventually after listening to the pieces rattle at idle esp, they all made their way to the tailpipe - my HFC was empty when I removed it to replace it with a different design (this on my '91 B13/SE-R, same principle).

I don't recommend ceramic based on how much easier it is to break down, and when it does, the cat is useless. I know my cat was slammed around a bit by some aggressive driving, too, but that happens, right?

My new one uses metallic substrates (sorry, this is on my SR20 in my '91 B13 SE-R, so can't help you make your exact choice here).

Also if you're concerned about emissions (duh) be sure that it is truly a 3-way catalyst. Some manufacturers claim this but skimp on the more expensive platinum and rhodium (and/or palladium) which are the primary substances to convert NOx to N2 and O2. The oxidation catalyst also uses platinum and usually palladium to reduce CO and unburned HC's.

A lot of AM HFC's, even some otherwise very good brand names, don't use enough of the more expensive metals and then you eventually fail emissions testing. At that point you have 2 very nice expensive fishing weights. Ask how much of each are in HFC, if the manufacturer cannot tell you, don't buy from them. Alternatively ask for test data demonstrating how effective their cat is for NOx, CO, and HC reduction.

I only mention this because I've seen people esp. in the Nissan I-4 engines get burned many times on this.

 

Umm...on the street, yes. But if you track your car, it's not such a slim chance as you might think...read my prior post. Coming off a berm at near triple digits will transmit a good amount of shock, no sheet...ceramic cracks, metal will too, but it takes a lot more work to do it.

 

so what is berks input on metallic vs ceramic for a non-track DD?

 

i am about to pull the trigger and get high flows, i have a nismo cat back, and guess im leaning toward berks, but which ones should i get and what happens if they crack, whats the warranty on them

 

One year

 

do a search on HFC and nismo exhaust. LOTS of people get cracked cats with Nismo exhaust

 

i have the nismo exhaust with tanabe y pipe and berk metallic high flow cats. i would never change out this combo, the sound is perfect.

 

I believe this is the key though. From what I remember reading, the Nismo Y pipe is the culprit for cracking HFCs, but I can't remember why.