how much boost will it run???

[94mx3rsr]

I own a 94+ mx3 and have a bp turbo running euro spec bpt mapping (german ecu), stock 4cyl fuel pump and pretty much everything stock (with a conic filter)<p>i put a turbo smart valve this week and i decided to up the boost a little bit...i went up gradually and this morning decided to turn the knob a little....i actually went up to 15 lbs and snapped 1-2-3-4 and everything went fine to the 7100 rev limit......the air fuel guage is in the green all the way just like at 8.5 lbs and the boost indicates stable 15lbs......i dont have egt so i didnt keep it up too long..<p>i was told the ecu had a 14 lbs of boost limit by some people who said the car stumble when it hits 14 lbs....i dont understand cause mine excellerated very smoothly.....???.....of course after hitting 15 lbs i turned the knob down a notch but let me say it hauls big time 13 sec car in my opinion!!!....(night and day).....<p>my question is ....is there really a 14lb boost limit on the ecu ....and second how much boost can you safely run on a 94+ 4cyl fuel pump?.......what is the lph???<p>
thanks!!!<p>JM

[torpedan]

Yeah i would say that fuel pump is being pushed beyound a safe limit. As of i hope you have some serious injectors in there too<p>
Most of the talk on here doesnt reflet upon those ecus. you would have to hit a european website they might know more.. most people round here run aftermarket ecu's<p>
Check around and do a serach in regards to a rx7 fuel pump there is a straight bolt in that will help with that issue.

[jaydog5678]

The 3rd gen Rx-7 fuel pump is what I'm using. You could also use the 2nd gen Rx-7 as well.<p>In order for the 3rd gen pump to fit, the Mx-3 fuel pump bracket needs to be modified slightly.

[maldo]

I would have to agree, you are seriously taxing the stock fuel pump. In regards to the boost question, the 323GTX and GTR have a boost sensor which sends a signal to the ECL, triggering a buzzer. This is the same type of system the 323GT and GTX from NA have. The ecu most likely is still capable of keeping up but I would recommend the egt gauge as you could be running lean above 12psi. A/F ratio gauges are just a bunch of pretty lights, pretty useless and slow reacting.

[Dismay]

You're asking to blow something up...