black smoke expelz from exhaust, sr20det

[MaKaVe1i]

i have a red top sr20 in my 89 fastback with power steering. upgrades include hks air filter, performance exhaust (just muffler), new bosh spart plugs, 20W50 sythetic blend, and i always use 91 octane gas,The problem is when ever im on boost, my exhaust expels black smoke . What should i check and repair?Also, it takes 2 or 3 tryz to get it started in the morning. pumping the gas pedal helps start the motor. when it doesnt start after an attempt, all i hear is somting turning (weird noise) though..,after the motor starts it idles at 1,500 rpms and takes like 5 minutes to warm up. after itz warmed up, the motor starts to idle at about 900 rpms. Also, my exhaust manifold gasket is broken, is this kausing any power loss or damage?

[[s3]]

You are running rich, check PCV to see if they are working properly, fix any vacuum leaks and yea that gasket too.

[Supafly]

what form of englizh iz thiz, replacing s's with z's? itz very confuzing.

and a muffler does not a performance exhaust make