I have 89 240sx with sr20det red top.with skyline turbo upgraded manifold,external wastegate. OK problem car sputter-brakesup when boost gauge reads more than 8 pounds of boost.does car need a fuel cut defensor to run good.thank you for any information

ok, he's either drunk or high.. nobody types like that sober or clean

Sounds like the spark is blowing out. Gap your spark plugs down a little.

did u upgread the fuel pump? sounds like it can't keep up?

thanks for info i replaced fuel pump and turned the boost down for now untill i install a fuel cut defensor

got any pics of replacing the fuel pump??

you need help changing your fuel pump? it takes like all of 20 min. If you need instructions PM me.

You don't need a fuel cut defenser. Ever hear of people getting a boost controller and running 14psi stock? Yea thats not the problem. Pull your plugs, clean them, and gap them down to like .030". Worst case scenario, you are sure it isn't your plugs.

i think having a clogged fuel filter, etc would also cause the car to break up on top. so yeah have your plugs checked, and change the fuel filter.

The Skyline Turbo is nothing the SR cant handle... its actually has a smaller A/R than the S15 T28. you didnt list a upgraded fuel pump so get one quick The 240SX can barely handle a T25 on 7psi so theres your problem