I have just got a 2001 RX-7 RB which is stock. If i put a 3inch Exhaust and after market air fliter how much HP/KW would get?

 

Zero, because the engine will be blown.

OK, maybe not quite that bad but the fact is you are significantly increasing airflow through the engine and the ECU won't know that. It will run lean, and will blow.

At the very least you're going to need some easy way to measure A/F ratios (such as a wideband) before you start modifying things. And a boost gauge.

There are several plug and play fuel controllers available for the FD, so check the FD forum FAQ for info.

 

As Aaron mentioned, the quickest way to a blown engine on turbo rotaries is to do a full, open exhaust and intake. If you keep the stock cat, you stand a chance of keeping boost within stock parameters but you really have to be careful since the FD's fuel system doesn't have much overhead for anything more than stock boost.

Read the 3rd Gen FAQ for more info

 

Please go read the FAQs in the 3rd Gen section before making any modifications to your car and to help you avoid asking questions that have been asked a million times in some form or another. We want you to enjoy your car and not blow the engine...so please spend some time reading...and welcome!

 

Thanks guys but i have also fitted a Apexi Power FC to the car with boast now set at 12psi max

 

Wow seems like the stock fueling system is really... subpar. Is it the injectors or the fuel pump that can not keep up? I had seen write ups on the horrible wiring and fuel pump voltage drop but is that the issue or is it that the injectors are just to small?