Will i need to convert to MAF with new heads???

I think you can. I hear people getting heads and intake on their speed density stangs with good results.

hopefully someone else can shed some light on this matter.

good luck

Yes you will have to convert to MAF. I just did the same thing your doing about 6 months ago, Edelbrock Performers, 306, but I already had a cam and intake. The car didn't run very well in first and second, then it would pick up in the rest of the gears. I did the MAF conversion 2 weeks ago, and its the best thing I've ever did. Car runs great, idle has droped down and is rock solid(you can hear the cam really well now, sounds extremely mean). The conversion is easier than you would have ever of thought. Get a A9L computer and meter, and but a wiring harness from IS&T that goes from the meter to the computer. Has great instructions, extra wire and computer connectors. Be sure to soder all the connections and splices. Its a piece of cake. By the way my car is an 88' too.

Casey