Originally Posted by
fallen4ng31
RS/GS models dont use a MAF, they use a MAP sensor. You'll need an FCD or a missing link to keep the MAP from seeing boost. 450's won't work without a resistor pack. 7PSI can be achieved with a 12:1 FMU on stock injectors, (Cheapest) but you'll need a Walbro 255HP model fuel pump. Also your injectors will be nearing 80-90% duty cycle with a 12:1 increase in pressure. An SFMU is more ideal, then you can utilize 450's with a resistor pack and run a little more boost. (Provided you're not using OEM internals.)
An AFC is a moot point at that level; If you're going to tune it either go with Megasquirt or a PortFueler.
Sorry man, I dont know dick about the 420a's, Ive just seen snapped rods from them that look like some shitty cheap cast china recyled scrap metal. I was trying to throw out there some common knowledge that his car wasnt going to mesh with a turbo as easily as he wanted to do it in his opening post, just tryin to point out it wasnt just a turbo, exhaust, and a BOV like he wanted to do with out getting all "fancy". But good info, thanks.
To the OP: Bottom line, even if you were to sneak by and get the bare minimum (doing everything right so you dont trash your shitty rods that a person could snap in there hands) look to spend a good amount of $$$$$$$$$$$$.