FD3S-Paul

Hi all

To be honest i am new to the world of RX7's and dont have a clue

Im looking to change my exhaust. I have found this one but sombody says there may be 2 cats. Will this remove all cats???

http://cgi.ebay.co.uk/MAZDA-RX7-FD3S...QQcmdZViewItem

Thanks Guys

grimple1

iTrader: (1)

read the faq's. the FD is not like a piston engine and is NOT a forgiving engine. 3 mod rule is a must know.


the FD has 2 cats.. a pre-cat and a the main cat.

FD3S-Paul

Hi, sorry im new to this site and cant find any info

dgeesaman

iTrader: (7)

Not in the UK. The pre-cat is a US only thing.

As far as the exhaust goes, if it's the only aftermarket part you have nothing to worry about. Change it. Leave the main catalytic converter alone.

Dave

FD3S-Paul

Hi, thanks for your help. The car is a jap import, so the de-cat pipe would not actually get rid of the main cat??

Mahjik

iTrader: (1)

It will. He is suggesting NOT to use that part. Just install the catback exhaust which it the 3rd and final section of the exhaust line.

Removing the main cat can cause uncontrollable boost. If you cannot control the boost, you can and mostly will, blow the engine.

Oliv

No my friend, European model also have this shitty precat.

RHD cars must mount only japanese style downpipe such as HKS or RE with a flat profile intsead of the precat.

Jites

Yeah, i have seen this first hand, don't decat without a remap. ever.

GoodfellaFD3S

iTrader: (213)

^^You resurrected this old thread to give out bad info ?

A remap/retune won't help with boost creep. Only porting the oem internal wastegate or (re) introducing more exhaust restriction will mitigate the problem.

MakoRacing

iTrader: (12)

+1

Jites

sorry guys, i was told that a remap would solve it, but cheers for the info as i was just about to have a remap done too. that would have gone bad...

again my apologies.

dgeesaman

iTrader: (7)

There is a reason why some folks think a remap solves this problem: it's because remapping can solve the issue of too much boost for a given fuel map. So if the stock fuel system can support 13 or 14psi of boost and the stock fuel map stops at 12psi, then when an exhaust change drives up the boost level from 10psi to 12psi that's one solution. But it's short sighted: what about the next change to the system? What if 12psi is not what you want to do given the mods and cooling setup? What if you don't want to push your turbos that hard and run that hot?

The real issue is not that really, it's the lack of control of boost. You can adjust the boost back down to 10psi and stop worrying. You can adjust it down further if you're going to a track day and you want an extra measure of reliability, or you can turn it up when you get your fuel system upgraded and remapped to handle more boost.