I'm still running stock cats on my gtm stage 2 ..23k seems to be ok so far...not sure if I wanna change it up and lose low end TQ...super chargers need all the TQ the can get

Don't know about the GTM kit but I felt no loss of power going from stock Cats to TPs, and more power at top end. There's a fine line between beneficial scavenging effect and straight up restriction. Those stock Cats seem very restrictive to me at least.

I keep the stock cats till they blow lol I have another set of stocks on standby a small well so I'm covered for a while at least

I wouldnt want to risk doing this. They could blow in a way they plug up the exhaust so bad that they damage the internals of your engine.

Pretty much.

When mine exploded, I pretty much shat a brick, thought 'it was over, engine exploded and the 370Z ride was over'. It was NOT a plesant experience, no idea why one would want to risk re-living that, not to mention the potential as TG said, that it could actually cause some permanent damage.

So is there any general consensus on which CATS are the strongest and most reliable for an FI build regardsless of how they sound?

Ive always heard Mil-spec are hard to beat. I have zero data to back that up though.

From what I recall, that's what Fast Intentions uses in their catted turbo exhausts.

Does anyone here have mill spec cats on their Foced Induction build?

If you're talking universal style Cats... Mil-Spec is more widely available in the US, Magnaflow are probably the best you can get in Australia.

If you're talking typical 'HFCs' in the stock location, there's a stack off-the-shelf options, though I doubt the success you'll have with them.

It's more to do with Cat location, not brand or type, in my opinion

In the Z32, Cat location was mid-system and there are plenty of F.I. Z32s with far more power than us with this setup, unlike the Z34 where Nissan decided to have the Cats up front, at the beginning of the system right after the headers.

:iagree:

FI put the cats much further downstream on my exhaust, and there haven't been any issues.

I'm looking at going with the Fast Intentions Resonated High Flow Cats. I'm not sure what they use as the cat (Mil Spec?) but I trust them to make the right choice.

Planning on ordering them very soon. Anyone got any experience with these?

Wouldn't you be better off using TPs in the normal location and having FI put cats in the lead pipes for the exhaust? It's how they do it on their 3" turbo exhaust if you want cats. Moving the cats downstream will extend their life greatly.

I'm not sure which is better, that is why I will give Tony a call today and see what he says. I already have their TDX exhaust system.

Just got off the phone with FI and will be going with resonated Test Pipes and the Mil-Spec Cats installed in the front pipes. 6-8 week lead time though........