New to nissans need help

[fastest94v6]

Hey all, just wanted to formerly introduce myself and ask a few questions. My name's Murad. I own a 98 camaro SS, 90 240 sx (just purchased), 09' maxima. The 240 has the sr20det swap and a t28 turbo.

First, I noticed my brake pedal is really hard. I bled all the brakes, and changed rear pads, still no luck. The calipers are moving freely. what could it be? Second, when i hit boost and am at about 5k rpms, the car makes a funny sound as if its hitting the rev limiter, but its not. Third, I wanted to change the plugs, what do you guys use in your turbo cars? How strong are these motors? I wanted to upgrade the turbo, but I just don't know if the bottom end can handle it. I appreciate the feedback, thanks.

[Oneandonly212003]

about the brake pedle try changing the brake booster mine was really hard to i bought one at a pic a part for 40 with the master cylinder changed it in like 1 1/2 hours

[fastest94v6]

Thats what I was figuring also. Thanks!

[fastest94v6]

Still having the problem. Going to check the proportioning valve.

[liquid_cool]

about the brake pedle try changing the brake booster mine was really hard to i bought one at a pic a part for 40 with the master cylinder changed it in like 1 1/2 hours

brake booster workes off of vacume..check the lines first..if you have.to see if there leaking or not.

[fastest94v6]

No leaks there.