ok so i have 90 s5 rx7 and i dont want to go turbo at the moment
so how much hp does each porting give you (example street port+100, extended port+150,
bridge port+ 250, and pp +300) < that me guessing http://www.mazdarotary.net/porting.htm and i did read it but cant seem to understand. and if you can tell me how much hp it would have on the engine i would appreciate it
and also what other major mod would have to be done other than intake and exhaust

 

extra 100 with a street port...........no if thats what you were asking

 

extra 20 whp with a street port?

 

it will shift your powerband more than anything else, adding more topend with at least some loss of low and midrange. you will pick up more peak hp, maybe 10-20, depending on what your exhaust setup is. I had a nonturbo and it put 172rwhp to the wheels with street port, header and full RB exhaust (no cat), pineapple racing auxiliary port sleeves, a tune and a bunch of other little stuff.

you might be as fast or a little faster than a stock T2 if you take the car far enough. It'll be a fun car but it won't impress anybody in a straight line, not with v6 family sedans having nearly 300 horsepower these days.

 

well will a bridge port give me at least 300. thanks guys

 

250 whp, if you're lucky.

And your motor will only last 30k.

And you'll be getting 10 mpg or worse in the city.

And you'll have a brap brap brap idle at 1300, which is a plus or a minus.

Don't forget the $2000 aftermarket EMS to control the higher rev range and fuel/timing requirements, plus you should probably change the intake manifold to take advantage of the higher powerband. Stock ECU will not control the BP well.

 

dam... thanks, i just didnt want to change the ecu if i have to change the ecu i will just go turbo
and swap it out... now another question is those j-spec or jdm engines why dont their ecu work
and if i just buy another ecu that is off an american rx7 will it work or no(start right up i mean).

 

J-spec ECUs have trouble running the injectors properly w/ US-spec wiring. A US-spec ECU will run it just fine. Read the FAQ or click the link in my sig. for turbo swap details.

 

thanks for the help.