Marv

Hey guys, I have a 90 N/A and was contemplating putting on a bonez high flow cat and removing the pre cats. Will I notice any gains and will I pass emissions? Thanks.

SpeedRacer

Yes, yes you will notice power gains. It will feel stronger in the mid to upper range rpm's. You SHOULD still be able to pass emissions, but there is not guarentee. No big deal though, just keep your stock exhaust to swap when DEQ time comes. It doesn't take very long to swap exhausts.

TCAT31

You'll definitly see a gain, although how much i'm unsure, I'm running the Bonez high flow cat with pre-silencer with a Greddy Power Extreme cat-back (installed all at once). I noticed a big gain in my N/A 89 but I don't know how much power to attribute to what. As far as Emissions, I live in KY and I had to get my E-check this past March. I passed with flying colors. Seriously, they had to raise my hood (couldn't get a reading with it down and then it barely picked up anything with it up). So good luck.

filraen

Its true,
I put on a bonez superflo converter system along with a RP50mm cat-back.
I noticed more power at mid- upper rpms and she passed like a new car at the smog check (here in vegas its yearly). Don't know if she'll pass with the bonez intake. We'll see.....

anyways before you decide, check into mindtrain headers and Apexi N1 Duals first . Note: that Bonez will not allow you to put a header on and RX-7.com will recommend against it. Everyone else (who has a clue)KD Rotary, etc. Highly recommends headers for best bang for the buck. i only wish I researched other avenues first before I made a ~$700 purchase, because I would have gone for the Mindtrain Headers, Mindtrain CAT or Racing Beat CAT, into Apexi N1 Duals. I have heard the N1 duals while I was in Japan this last summer (and the N1 singles under WOT) and I am kicking myself in the butt over it now!


REsearch....Research.....Research!!!!!! Remember think Modular: Pre-cat/ CAT/ Cat-back. Bonez is a decent CAT but it is not Mandrel bent and prevents the use of a Header <(unless you have a powersaw and welding skills handy)>.

And dont forget your intake. I would lean toward Apexi power intake since the Bonez doesn't clean as well but way better than HKS. And the instructions that come with the bonez intake was a joke and confusing. (I felt like I was buying it from a garage sale) At least it's an easy install (monkeys could figure it out!)

Just my $.02
M:p

Rxmfn7

iTrader: (4)

yes, definately a noticable difference. I had mine with the stock mufflers , and I still felt a gain. Also passed emissions perfectly. ran really clean. Now that I have an aftermarket cat-back, there is even more of a noticable difference. Definatley beats those damn restrictive stock cats, with such small piping. I would definately recommend it. Rx-7.com has some of the best products in my opinion.

Rxmfn7

iTrader: (4)

just another of my .02c, I would recommend getting the superflo system, and not just the main cat replacement. It will five you all the piping from the exhuast manifold to the y-pipe, mandrel bent and stainless, well worth it. Just my opinion though.