max horsepower for a NA build?
 

Does anybody know what the most horsepower I can expect on a NA build for my RX8?

220whp

/thread

really? thats all even with portin and polishing it, headers no midpipe addin larger injectors etc?

renesis is garbage, dont waste your time and money :D

You are most likely making the same assumption that most newbies do.

Most piston cars aren't making their potential from the factory, either through factory de-tuning, lack of developmental and advancement funding, or lack of a desire to push the vehicle upmarket more.


The RX-8 is entirely different. Mazda didn't hold anything back in seeking as much power as they could NA. There are only 2 things you can do for noticable gains:
1: Remove CAT, install midpipe. Mazda HAD to have the cat in there for the EPA and regulations and such, and it is something that reduces power. Estimates are around 10hp.
2: Get the engine re-tuned. The factory tune is a bit safer and more mild than it could be, mainly as a generic tune across the board that is still VERY VERY good. That being said, it is a generic tune, and there is a 5-15hp gain by getting a custom tune for your specific engine. How much depends on how close the factory tune is to ideal for your engine.

The 'breathing' mods, intake, exhaust, etc... don't produce very much in gains, because they are designed very good from the factory. Speedsource uses the stock airbox and filter in their Grand-Am ST class cars, because it is that good. There ARE gains from a header, but 5hp is the max you will see from anything out there.

Even full race teams that can dump $30,000 into an ECU (for example), haven't made it much above 220whp.


If you want power, save up at least $10,000, and go forced induction.

there must be a hundred of these threads, but here goes a couple things anyway.

- porting and polishing all the LIM and exhaust, headers, catless midpipe all togetherwith no other mods might win you 12WHP. I didn't mention injectors because bigger injectors are useless. The OE injectors can support well over 250WHP.

- the best you can do reasonably is 220WHP. That involves some intake work(potentially even semi-custom), some very good tuning, cat deletion along with other exhaust mods

you could possibly pull out another 15 or so HP with porting and cleaning up the LIM/TB etc... but is that even worth it?

if you REALLY wanted to get serious, you could put down 240WHP. But its gonna cost you thousands in engine management alone, plus all the other costs like intake/exhaust port/mainfold work. Then consider proper tuning, it takes the best of the best in tuning to get there. how do you aquire such tuning and whats that gonna cost ya

Too much Forza or Grand Turismo.

appreciate the help guys looks like time to decide on a turbo. you also got it right first rotary engine for me so i have no fuckin clue what to do with it.

thats okay we will help you out (by we i mean the rotary gurus on here). they sure helped me out a bunch when I first got mine.

Read through the stickies oh here as well