projectresto83

Ok, sorry I didn't say more of the front of the head but here you go. See the GT marking on the exhaust side of the head? That is what you want to look for.

berserker336

It does say gt on it. I suppose that is an indication that it is a 302, though the seller told me he did put gt-40p heads on the engine. Is there any other means of identification? I dont guess its a big deal because Ill enjoy it either way thanks for all the help!

Tony71502

Of course it is a 302. A 306 is simply a 302 with enlarged pistons. Only 0.03 inch enlargement of the piston head (diameter) yields an extra 4 cubic inches of displacement.

The GT on the cylinder head indictes they are GT-40 heads. In your case, gt-40p.

The seller told you correct information as far as I can tell.

You may have a block from a cobra... or a regular mustang. Either way, you have the heads and intake that cobras were fitted with and either engine combo will make the same power not considering the cam.

berserker336

Gotcha! and now that I look at the heads, Im lucky i didnt have to do the smog pump. There isnt any thermactor holes...

Tony71502

Are you sure? There are two holes in the picture project resto posted above the casting plug.

One large and one small. The small hole is for the bolt that holds the thermactor tube on the back of the cylinder heads. The larger hole(also with threads) simply flows the gas to the thermactor tube. The reason this bigger hole has threads is because the bare cylinder heads are identical and when used on the other side of the engine, a threaded insert is put into this hole so you can mount your accessories like the alternator, etc.

projectresto83

So true, when I first got my 83 running a few years ago I didn't notice that I put them on backwards so one night when I was out working on it I noticed a pretty blue flame being shot out from behind my power steering pump. Know wonder why the motor was so loud from the engine bay...