the difference between MAF and speed density is
1-maf was from 85-87, speed density was from 88- on
2-you need a chip if you do any modifications to speed density (MAf will compensate up to 12% performance improvement)
3-you can convert MAF to S D if you change the computer and block off the 9th injector
4-if you get a chip burned for SD it will work better than if you just modify a MAF setup
5-removing the screen and cutting the cooling fins down on the MAf unit will improve flow
6- removing the casting blocks behind the throttle body, installing an AEROFOIL in the the throttle body, getting a cold air kit with smooth bellows in place of the factry corrugated hose, and installing and setting up an adjustable fuel bressure regulator will give you a 7 tenths improvement in both MAF and SD setups
7- factory TPI setups were designed for 305 engines, 350's were used from 87 on and the same intake was used hindering top end performance on the bigger cube engine
8- if you want lots of torque and dont plan on going over 6500 rpm a TPI will work for you
9- if you already have a TPI setup you can buy the aftermarket upper, lower, and runners and be able to go up to 7000 and sometimes beyond
10- both setups are usable with 700 trannys
11- SD has nothing to do with the speedo
12- you are better off using SD when going the turbo/supercharger route either way you will still need a chip burnt for it.
hope this stuff helps.
