360-340 heads on a 318 poly?

Just wanna see if you guys can help me out here:
I'm trying to see if i can fit a pair of 360 or 340 heads on a 318 poly.
the poly is a 1966 318 out of a belvedere II.Still looking for Some heads so if you hear Anything Let me know

The Poly 318 has a different intake and exhaust spacing vs the LA 318/340/360.The LA motors have siamesed center exhaust while a poly has evenly spaced exhaust.Cams would be ground differently,not sure an LA cam will fit in a poly block.Lifter spacing and angle is another thing to look at.What is wrong with the original poly heads for your car?
RT

Moparaddict said:

Just wanna see if you guys can help me out here:
I'm trying to see if i can fit a pair of 360 or 340 heads on a 318 poly.
the poly is a 1966 318 out of a belvedere II.Still looking for Some heads so if you hear Anything Let me know

Click to expand...

This is the deal. I just went through this at FABO. Here's the skinny.

In short, no, unless your a master welder.

The "LA" head will bolt onto the Poly block because the blocks are extremely similar. With a few minor differences, there basically the same. the one big difference is the water port on the Poly drivers rear, passenger front that is inside the valley to cool the intake. It is not there on a "LA" engine.

In order to use a "LA" head on a Poly, you would have to weld up (Close off) these water port, tap the sides of the block in the lifter valley to remove coolant and plumb it to the "LA" intake/head.

Sound like fun?

You can use a "AL" cam since the cam tunnel is in the same spot with the correct size journals for the cam. Once you have the "LA"heads on, then a "LA" cam is what you would need. It would all work (Valve train issues) without a hitch. No angle issues to contend with.

Below is a "LA" head on a Poly block. You can see right under the drivers 2 intake ports, the water passage that comes up from the block. Some of it is exposed and it would simply gush water out if you tried to do this.

Below are some shots, top, the Poly, look closely.
Next, the "LA", look closely again at the these 2 shots and compare the middle & rear of the cylinder head deck surface. Do note extra bolt holes? Water holes.

3rd shot, the 2 engines I played with to see WTH is going on here.

In the top shot, note the "LA" head sitting on the deck. The 2 holes at the middle and rear sides of the drivers side of the engine are reversed on the passenger side. Not the water holes are at the middle front and front just under the cylinder head as noted by 2 humps outwards into the lifter valley.