Mustang Sally 65

Hey gang- OK here's the scoop. I have purchased a couple of heads for $100. They are a gt40 head and the ID casting numbers are: F3ZE-AA then a 6090 at the top. They came out of a 97 Ford Explorer but the casting numbers show it as a 1993 Mustang Cobra 302. I currently have a 302 out of a 73 Ford Torino and was wondering of these heads will directly fit this motor or if modifications will be needed? I have an Edlebrock intake and a set of headers for the car that were mounted to the motor originally. The original cylinder heads were a D0OE that say 302 and 69 below them. There is also a 15 and a B further down. What do you guys personally recommend? The GT40 Cylinder heads or the D0OE heads? And what are the cc's on the DO0E heads? How much modifying is needed to the gt40 heads to fit the 302?

Thanks
Mustang Sally

OCHOHILL

They should work. I would use the cobra heads. You will have to cc them yourself or have a shop do it. Milling the head will change the combustion chamber size. As for makin it work, you should check for a smog hole at the back of the head. I am not sure it is there, if so, plug it with a small plate that gets bolted on.

Mustang Sally 65

OK. The cc's on the cobra heads are 60-63 cc's according to the information I got. I do not know what the cc's are for on the D0OE heads though. Any input would be greatly appreciated. Also, does my information sound correct as to these being Cobra heads?

Mustang Sally 65

Also, if I use the push-rods and roller lifters from the Explorer? I am planning on putting in an edlebrock performer that comes with lifters. Should i use those lifters or should I go with the roller lifter and push-rods that came with the cobra motor? My biggest worry is which lifter to go with and which length push-rod should i use? I still have the pushrods from the D0OE also.

OCHOHILL

I'll try to give you a quick rundown, but you need to do more homework.

heads
You have to cc the heads yourself. They may have been milled in the past and that would change the combustion chamber size. Either head cc it yourself or have a shop do it.

You haven't mentioned this but you need to know the displacement of the pistons in your engine. This combined with head cc and head gasket thickness will determine your static compression ratio. You do not want an engine with too high or too low compression ratio. Not only is the actual engine displacement important but also the displacement of the piston head itself. You may have flat or domed pistons. These will come with different displacements and it will affect the compressed volume of the cylinder.

rocker arms
You could use whatever rockers you want. Some will require guideplates with certain heads. Others will require guideplates, period. Do your homework on this one. I am sorry I can't help you.

pushrods
You are assembling a bunch of different components that will alter valve rocker geometry.
The problem here is incorrect geometry will push the valve stem sideways in the guide. Poor geometry can wear out valve stems quickly. The only way to check is to assemble the engine and check the optimum geometry with an adjustable pushrod. Measure the length and order a set. Do some homework on this. There are several articles in magazines and websites for this. You can also try buying a book on building performance engines. There should be a section on this.

Lifters,
Roller cams need roller lifters. Roller lifters can be re-used if they are in good shape. Flat tappet cams need flat tappet lifters. Regular flat tappet lifters are mated to the cam during break in. When removing flat lifters they should be labeled and placed back in the same position on its' mated cam. These should not be reused on another cam shaft.

The reason for this is flat tappet camshafts have a slight bevel to them. They are not cut square. The bevel is designed to rotate the flat tappet lifter in its bore a small amount each time a revolution is completed.

Roller cams and lifters are the way to go. This system can ramp up lift faster. This quality enables a performance camshaft to have a stock idle. Plus, there is no worrying about flattening a cam lobe.

valve clearance
Something else that should always be checked when assembling a rainbow of parts is the piston to valve clearance. Your pistons may not be designed to clear the valves on the GT40 heads. Read up on this as well. It will require a mock up assembly of the cam, crank, 1 piston, lifters, rockers, head gasket and correct pushrods.

You can do it. Do your homework.

tx65coupe

If those heads of off of an Explorer, they are probably GT40P and will require unique manifolds/headers.