since there is a fuel filter and in line external pump on the 84 svo, how should I change the stock in tank pump? do i need to upgrade the external pump also? i'm gonna run a 190
You need to yank the inline pump. This is easy. On the SVOCA.com board you can run a search and find the particular part # fuel filter that goes in place of the inline pump. Or, go to the autoparts store and buy replacement fuel line (plastic) that SVO's use and the barbed fittings. Pull all of the inline pump hardware out, reinstall the new fuel line in it's place. Put the fuel filter in back closer to the tank.
-that's what I did anyway, as it gave more clearance for my 3 inch exhaust.
Then, get a fuel pump bracket for an '87-93 LX or GT, engine size doesn't matter. This is the bracket that drops down inside the tank. Your SVO pump bracket won't work with the new pump, so you can't use it. Once you have the new fuel pump bracket in place, go topside, open the hatch, move the mat aside, find the wire harness going to the tank, there is a black braided wire going to the fuel pump. This is a resistor wire to protect the old pump. You need to disconnect it, add a regular wire in it's place and ground it to the body. It's real simple and easy to do. More info on the SVOCA board.
I'd also just spend the $10 more and get the 255lph pump. Make sure you get the "high pressure" model.
I second the 255HP pump...don't waste your money on the 190...the 255hp is only like 95 bux on ebay.
Buy two new fuel filters...the stock unit and one for a mid 90's (93 for example) Explorer. Both filters will look identical except the explorer unit will have a longer inlet/outlet.