ok my car is a 1986 rx-7 n/a it needs a exhaust so im running a 2 1/4 with out cats will resonators take the place for the back pressure it run or no cuz right now i have no exhaust on it and it only does 55km is that cuz of no exhaust

 

like mph.

 

no i mean 55 km im from canada it has no exhaust on it and i have no power theres no black smoke and i need to keep my foot on the gas to keep her running

 

hmmm, well you only need the back pressure to operate the 5th and 6th ports, if that was the case you'd have plenty of power up to about 4k rpm, what your describing sounds like a bad motor.

 

the motor is slow to rev but i was thinking since a pistion car is slow to rev when i had a leak in the flex pipe thats uy my car wasnt reving fine and when i get it started after so many turns it will die i need to leave my foot on the gas to make it run and i thought if there was black smoke the motor was bad

 

can you type alittle better please? i have no idea what your saying,

1. you can't compare problems you've had with a piston motor to a rotary.
2. have you done a complete tune up on this car yet?
3. have you done a compression test?
4. white smoke= water seals are bad (motor is toast) , black smoke= many different types of bad ( most likely soon to be more toast)

 

exhaust won't fix your problem, you have some other serious issues with the car that need to be sorted out like a compression test first.