Cats Do I Need Em 89 Turbo II
 

Well Im new to the rx-7 world but have been around the import scene Forever. im just Curious Do I need my Cats? i just Purchesed an 89 turbo II I want to eliminate them with downpipe n upPipe. Or Empty them Out... Has any one done this? There should be enough backpressure because the of th turbo. Oh and emmisions arent a problem....Thank Goodness for Dealer Plates.

No problem gutting cats, except for the environment, but depending on the size of the dp you could run into some fuel cut or high boost pressures so you'd better upgrade the fuel system and add a fcd. Do a search as it's been asked many times.

Thanx Turbo Nut I have had this Post on my Local forum n the guys think Im Crazy. Saying things like Its a Rotary Its different well Its still a Turbo Motor so same concept. U r the MAN!!!

Gutting the cats alone will allow boost to overrun the stock controls & fuel.
Power goes way up for a second, then pingety ping - rattle - sputter, sputter.
Driver says "O-Shit, I should have listened."

To control boost before allowing it to increase, the waste gate must be ported.
Then you must add fuel as you dial up boost.

It's the age old rule: FAST - CHEAP - RELIABLE (Pick two)

Like Sureshot and Turbonut have said, upgrade your fuel system and get a FCD. If you plan on running the stock turbo for a while, but at higher boost levels (over 8-10psi) your going to need a walbro or FD fuel pump. Most importantly is a Fuel Cut Defender (FCD) from racing beat, HKS, creeping death, etc. Porting the wastegate is reccomended.

IMO, if you intend on running the stock turbo over 10psi, I would do the following:
1.) Fuel cut defender
2.) ported wastegate (30mm, larger?)
3.) 720cc secondary injectors
4.) rtek v1.7 chip
5.) S-AFC
6.) walbro 255lph fuel pump (rewired)
7.) at least 2.5" Down pipe and exhaust (high flow cat. if needed, or gutted cat. for visual inspection.)
8.) high flow intake and air filter
9.) aftermarket boost gauge
10.) boost controller of some sort
11.) turbo timer

Doing the above will set you back a little, but should yield a fairly considerable performance gain. If you ever intend on running a hybrid turbo (BNR), I would go with a 3" exhaust, and a greddy e-manage rather than a S-AFC. There are a lot of options, it all just depends on how much you are willing to spend, and your power goals.

~Chris