Tom, looks like you have the original 250hp 400 with approx 8.3-8.5:1 compression ratio. The heads are likely 7K3 not 7KS and should have 96cc chambers and 2.11" intake and 1.77" exhaust valves. It would be a good start for a street performance build, mill the heads a bit to get it around 9:1, add a mild cam, headers and exhaust and gears to match.
Steve  

thanks what kind of cam would you suggest ?  

How much power are you looking for  

at the end i'm looking to build up to 400 horsepower . i dont wanna get too crazy .i need a reliable car as well as powerfull.  

so i'm having another type of issue . the engine wants to start . it turns and if i put gas in the carb it chugs once or twice . but its not getting gas . i dont know which line to disconnect and i also ( embarrasing) cant figure out where the damn fuel filter is located on my car . so yeah . which of the many lines connected to my tank do i need to disconnect and blow out ? i need help bad.  

Tom, the fuel filter is located inside the fuel line fitting at the front of carb. Hold the large 1" nut with a wrench and use a 5/8" line wrench to remove the fuel line, then use the 1" to remove the filter fitting, the filter is inside (a paper element about 1 3/4" long). When replacing the filter, be sure the open hole in the end of the filter faces outward toward the line and be sure the spring is still in place in the carb body, be very careful starting the threads of the filter fitting as they can easily be cross-threaded, ruining the carb body and don't over-tighten it- snug is good, then reinstall and tighten the line.
As for the no-fuel issue, the car has been sitting for some time, follow the fuel line down from the carb to the pump. At the pump there will be a rubber hose to the fuel line at the frame, check to see if it is cracked and sucking air and replace if necessary. There may be two lines there, you want the large (3/8" inside diameter) rubber line and 3/8"O.D. steel line, the other is a return line that should be inspected for leaks as well. Follow the lines along the frame to the tank and inspect for cracks at the rubber line near the tank, I had the same issue when I bought my Formula, the rubber had dry-rotted and cracked open letting the pump suck air.. no fuel. I drove it home with a jerry can under the hood and a rubber fuel line going fromthe pump to the can. It's also possible the main lines or the lines on the sending unit are rusted thru or cracked too. To check the sending unit you will have to drop the tank, hopefully you didn't put too much fuel in it. If it has been sitting for a long time you may need to have the tank flushed out, you wouldn't believe how much crud forms in the tank when fresh fuel isn't being added. There is a brown slime from the fuel going bad, plus rust from condensation which forms when the tank isn't kept full. My Bird was awful after sitting for 15 years, even after flushing the tank it still plugs filters on a regular basis and will need a new tank to fix it.
Good luck,
Steve  

your my guardian angel right about now . i was so lost . is there another filter in the bottom of the fuel pump ? i've heard of those in fords . i just wanna make sure i dont hurt my engine while trying to get it going again . but like i said thanks alot man you saved my bacon i was unable to find any info online about it or any diagrams .  

The only other factory installed filter is the "sock" on the pickup in the tank. All it really is, is a strainer to keep large particles out of the fuel pump.
Try removing the rubber line from the pump and hook up another rubber line and run it to a fuel can, if it still won't suck up fuel, the pump is bad. If it runs now, the problem is aft of the pump, either the lines or the pickup.
Steve  

i went ahead and did that . it worked . i had it running for about 5 minutes till the valve covers started leaking and i realized that my carb needs to be rebuilt . i jumped the gun and tried to run it before rebuilding . but i could not get it to idle well or rev at all. but i get another check soon and its gonna go into the car . i hate waiting for money . well thanks alot guys . i'll update when something new develops . question . . . .i know this might spawn some negative feedback but i'm torn . between keeping it semi original or working it up . . .its not a super rare car so i dont think i'll hurt the value too much . what do you guys think ?  

Tom, your 72 GP is definitely a cool ride on it own, but you are right, it's not going to hurt to customize it to your personal tastes. Not knowing how it looks right now, all I can say is I would concentrate on getting it running right and driving safely before going too far. A good carb rebuild, fix your fuel issue and new spark plugs/wires/cap and rotor to get it running, change all the fluids and filters. Get a nice dual exhaust on it and maybe some 15" wheels (I'm partial to Rally2's, Honeycombs or TA Snowflakes, but aftermarket wheels are nice too) with some whiteletter tires 235 or 245/60r15's up front and 255's in back will look great. Be sure to take care of any brake and steering issues, then concentrate on the body and paint. I suggest keeping whatever factory color came on the car so the interior matches, besides those early 70's colors look so cool compared to the boring choices today. It seems most cars today are some shade of silver/gray, black, white or red. What happened to the neat blues, browns greens and golds? Get some pics up so we can see this bomb!
Steve  

well i'll try to get some posted soon . whats a good site to post on ? can you post on this one ? i have alot of pics right now . i just need to post them where ya'll can check them out .  

ok . . . new problem . . .so whats going on with this buzzing noise i hear whenever i hook up trhe battery? its really aggravating .  

posted some "before" pictures on readers rides section of this site . let me know what you think ? cant post without asking a question . my kickpanel says body by fisher ? what doesw that mean ?