How Much $$$ To Put A 69 351w In My 88 GT???

[Unit 5302]

Either way, you should be running higher octane fuel. If you have the 4V model, 10.7:1 is some serious compression on iron heads. Back in the 60's they ran leaded gas, the lead raised octane performance of the fuel.

Also, those heads were meant to be run on leaded fuel. Running on unleaded will probably ruin them pretty quick.

1969 2V 351W Gross ratings: 250hp@4600, 355lb/ft@2600rpm
-9.5:1 CR.
-350cfm 2bbl
-1.84" intake 1.54" exhaust.

1969 4bbl 351W Gross ratings: 290hp@4800, 385lb/ft@3200rpm
-10.7:1 CR.
-470cfm 4bbl
-1.84" intake 1.54" exhaust.

Crank: Nodular Iron
Rods: Forged
Pistons: Aluminum "Autothermic" Sounds like extruded, or cast.

Keep in mind, those are GROSS hp ratings. Although the ratings are probably a little conservative, you can take quite a bit off due to gross vs net adjustments in output.