WinPR

Guys im not sure about this but i've known that taking the catalytic converter out and put something like a straight pipe is'nt a good idea for an automatic FD3S? Unlike the M/T guys that to decat will bring them more HP!

And i've known that it will eats more gas than usual too am i right about this?
pls help !

PS. sorry for my bad english.

altec_fc3s

Decatting the car will increase the horsepower, transmission is irrelevant.

gracer7-rx7

iTrader: (16)

It can be bad to 'decat' any turbo rotary b/c the exhaust flow can increase too much by removing the restriction. The lack of restriction improves air flow and often overcomes the stock boost control system. This becomes a problem b/c the stock fuel system can't support the increased boost level. If you make more boost than the fuel system supports, you run lean and risk blowing the motor.

If you are going to remove cats on a turbo rotary, you need to ensure that you have proper boost control and proper fueling.

dreed7235

iTrader: (3)

I concur.

WinPR

i thank to you guys now i know of it more!

right now my cat is very old so may be i should buy one of those magnaflow cat from the US? (i'm assuming it's a good stuff since it's in US lol) and the price of it is pretty low too cuz here in BKK we would've buy a new catalytic for at least 500$+ or i may have another options to keep my wallet fat with cash? any suggestions pls?

and im not sure about how big the diameter is for my FD3S stock exhaust right now i'm using the RE amemiya dolphin exhaust with has about 80 mm. Is it any chance too big for my stock 13b Auto Trans engine which has 255hp? in my opinion i think with auto trans is unlike the manual cuz if the diameter is bigger it would takes more time to get the to rpm the the gear will swap am right or not??

gracer7-rx7

iTrader: (16)

Where exactly is BKK???

If buying from the US, try rx7.com. They have one of the best high flow cats. Pettit Racing also has a good unit.

Do you have a problem with the current cat? If it ain't broke...

WinPR

ฺBkk is Bangkok, Thailand. i found that magnaflow ceramic cat on ebay is it a great product?
My stock cat is not on my car anymore now it is a straight pipe. I do notice that the to take the car from 0-60 without stepping on more gas is really slow but to take the car up to 110 mph on a high way is faster without a cat. I don't get to do that often though cuz i live right in downtown. So should i get the cat back on then.

PS. now my car can fart out backfire!