earlqhan

iTrader: (5)

Hi guys, I want to build a N/A 13B (too many variations for me to keep track of), but basically what I want is:

1. 200WHP (give or take, not picky with exact numbers)
2. High revving (the higher the better)
3. Carb'd if possible (EFI can be done if it is necessary)
4. Cheap (but keeping it reliable, if one route offers better reliability for a bit more money, I'll go that route)

So please tell me exactly what I need to do, what parts I need, off which motor. This is the first time I've done anything with rotaries, so please excuse my ignorance, I'm coming from a Subaru background.

This motor may go into a '91 Miata, but most likely a '67 Datsun 1600, hence the want for a carb set up.

Aaron Cake

iTrader: (1)

I don't know why you would want a carbureted engine just because you are swapping it into another vehicle. I guess it makes certain things a bit easier but that just seems like the easy way out.

You've asked for three things which are mutually exclusive: powerful, cheap and high revving.

How high do you want to rev, and why? The S5 NA is the highest revving RX-7 engine with a redline of 9,000 RPM. If you build an S5 NA engine you should be able to do 200HP with a good exhaust system and a good tune (which means a standalone EFI system and not a carburetor). If you are willing to sacrifice drivability, low end torque, easy starting and fuel economy, a short IDA style intake manifold with a Weber will get you into the 200HP peak area for little money.

His&HerFC3

im going to start my build soon its a 13b NA and i wanna keep it NA can you port things like you do on a normal engine what are the ways to add power to an NA rotary sorry im new to this

Aaron Cake

iTrader: (1)

There are just as many porting options for the NA as there are for the turbo. What are your power goals, budget and primary use for the car?

fcs3l0ve

ways to add power to the rotary engine are similar with any car, start with a new exhaust system and air intake, light weight pulleys, new belts, spark plugs, and spark plug wires, and there are many different porting options for the rotary engine.

philly101

i have been needin help on this to cuz alot of people say 200 hp from a na waist of time

fcs3l0ve

it's not a waste of time, it's up to you what you want to do with your car and where your money goes with it. if your looking for 200 hp right off the bat then your best bet would be to do a turbo 2 engine swap into an n/a or just buy a turbo 2 rx7 altogether. 200 hp with an n/a could be done with a new exhaust, new air intake, emissions removal, p/s and a/c removal if you have them, upgrading the fuel system, light weight pulleys, porting the engine which requires a rebuild, a stand alone ecu, and a good tune and i'm sure there are many other ways to get 200 hp from an n/a.

philly101

wha kinda of fuel system would u go with an wha kinda port would u do

fcs3l0ve

you can get bigger fuel lines and run a walbro 255 lph fuel pump or a turbo 2 or 3rd gen. rx7 fuel pump and higher cc injectors. if you do that maybe you should get an upgraded ecu and get the car tuned. you can do any port you want but if its going to driven on the street a lot then a street port would probably be best.

Aaron Cake

iTrader: (1)

There is no reason to upgrade the fuel lines.

There is probably no reason to upgrade the fuel pump and injectors on a 200HP NA. Certainly not if you have a standalone.

fcs3l0ve

well there you go, he knows alot more about rotaries than i do.

o-hi-o

I'm interested in this as well. I've been doing a lot of reading on this forum (bought my non-running naturaly-aspirated about a month ago) but have a hard time separating the high horsepower junkie builds from the stock and lightly modified builds.

Aaron Cake seems to be the resident (and very patient) guru here. Is there a good place to find hp or torque gain estimates for different bolt on parts, ports, ecu tunes, etc.? I've learned a ton from perusing the faq and stickied sections, but still feel unsure of what benefits and drawbacks there are to different modifications on the s5 na.

BTW, this forum is a great resource. Thanks to all that are keeping in organized and informative.

fcs3l0ve

all you have to do is search the forum and read as much as possible if you want to learn. that's why i've been doing since i joined and ive learned tons of stuff about my car i never knew before and im continuing to learn more.

Aaron Cake

iTrader: (1)

Yeah, searching is the best bet. There is a thread in the 2nd gen archive called something like "how to make a beefy n/a" which covers the basics of NA modding. Your two main gains in NA form from bolt ons will be the exhaust and intake. With those upgrades, a well tuned standalone and a little luck, 200HP can be done.

Don't discount "tuned standalone" as an extra because that is were most of the gains come from. A proper tune is worlds better then the OEM map.