valve size

I was wanting to find the valve size on a 1989 stock 302 gt and what heads or size valves to use when converting to a 4bbl. carb.

Acording to Mustang Performance Handbook, your '89 G.T. heads came with 1.74" intake and 1.46" exhaust valves. Out of curiosity, why are you ditching the EFI?

Quote:

I was wanting to find the valve size on a 1989 stock 302 gt and what heads or size valves to use when converting to a 4bbl. carb.

I used a 1.94 Int & 1.60 Ext on a stock head, you can purchase a set of heads already done with these valve sizes installed for under $500.00 bucks, so do not spend you money on installing valve to this size, it is not worth it.

If you port the Ext. ports on the heads you purchase you will gain HP & Turq too.

Then add some nice headers, You will gain HP & Turq too.

Add a small cam, you gain HP & Turq too.

Now ----- NOTE --------
Do not go to big with the carb.
If you do it will make you suffer big time in HP & Turq.
If I remember right (Do not know) you will have about 225HP stock motor and with the above mods you will not gain to much more in HP or Turq, about 245HP upto 260HP.
So you could use a 500CFM two barrel Carb or a small 4 barrel carb only.
This is the biggest mistake - including me (Make), we over Carberate, feeding to much fuel is not good and robs power & Turq.