We are working on a 318 4 speed Duster. My son found a truck today in the JY with a set of 714 heads. He was looking for some 302s. The heads are still in the JY as it was closing time when they got one off and I was not there to help confirm a few things.

I THINK that on this motor they had pushrod oiling vs oiling through the rocker shaft. I have been reading different threads where guys were bolting these heads to their earlier 318s. I know about the swirl port, 62cc chambers and small runners and valves. With all of this being said, I would like to get them to put on his Duster.

The question is, will they oil the same as the heads on the 70 318 that is in the car now? Can we bolt them on with the 70 rockers and go?

Thanks

Look for the oil hole next to the head bolt hole...if it has this hole that exits to the head bolt hole then to the rocker stand, you can use the head on the older through deck oiling engine.

Those are supposedly the last production LA318 heads and may possibly have improvements over the 302s, in the area of durability.

I'd be tempted to buy the entire junkyard motor and rebuild it, unless you already have a roller cam block.

I am unaware of any LA motor that oiled through the pushrods. Magnums did, but many early Mag blocks have the oil passage in the block, showing that Chrysler didn't make coordinated changes. Maybe they were trying out the new-fangled idea of pushrod oiling.

The only way to be sure is to look at the heads and see if they have the oil passage feeding the rocker shaft. You could also get the rockers off that same engine and see if the pushrod cup has an oil squirt hole.

The pushrods on my '86 were solid ball, and Rockauto shows that. But they show a pushrod with a hole in each end for the 1991. My hydraulic rollers had no hole for oiling the pushrods. Later ones and also the replacements for the LA318 have the hole.

Steve Dulcich's article on porting the 302s included a lot of information. Don't go as far as he did because his cracked in service after he did major porting. The pushrod pinch restriction I believe comes into play only after the bowl is working. I trimmed it down quite a bit but I seem to remember the valve bowl and the valve guide being more in need of work. It seemed to me that there was a lot of material in the roof of the port and maybe that was a way to induce swirl. I opened it up quite a bit and trimmed down the guide "island".

The heads would really like a piston with compression height greater than what your '70 318 has, which I think is 1.720, 8.2:1 in your application. These are the flat tops with four valve reliefs. The valve reliefs are a joke because the piston is 0.100 down from the deck. The best stock pistons have a compression height of 1.755, Sealed Power H814CP, 0.067 down in the hole in a 9.6" deck, giving you 9:1 compression. The Keith Black pistons will be 0.012" down in a 9.600 deck, they weigh less and cost more.
It's your dollar.

R.

Those are supposedly the last production LA318 heads and may possibly have improvements over the 302s, in the area of durability.

I'd be tempted to buy the entire junkyard motor and rebuild it, unless you already have a roller cam block.

I am unaware of any LA motor that oiled through the pushrods. Magnums did, but many early Mag blocks have the oil passage in the block, showing that Chrysler didn't make coordinated changes. Maybe they were trying out the new-fangled idea of pushrod oiling.

The only way to be sure is to look at the heads and see if they have the oil passage feeding the rocker shaft. You could also get the rockers off that same engine and see if the pushrod cup has an oil squirt hole.

The pushrods on my '86 were solid ball, and Rockauto shows that. But they show a pushrod with a hole in each end for the 1991. My hydraulic rollers had no hole for oiling the pushrods. Later ones and also the replacements for the LA318 have the hole.

Steve Dulcich's article on porting the 302s included a lot of information. Don't go as far as he did because his cracked in service after he did major porting. The pushrod pinch restriction I believe comes into play only after the bowl is working. I trimmed it down quite a bit but I seem to remember the valve bowl and the valve guide being more in need of work. It seemed to me that there was a lot of material in the roof of the port and maybe that was a factory way to induce swirl. I opened it up quite a bit and trimmed down the guide "island".

The heads would really like a piston with compression height greater than what your '70 318 has, which I think is 1.720, 8.2:1 in your application. These are the flat tops with four valve reliefs. The valve reliefs are a joke because the piston is 0.100 down from the deck. The best stock pistons have a compression height of 1.755, Sealed Power H814CP, 0.067 down in the hole in a 9.6" deck, giving you 9:1 compression. The Keith Black pistons will be 0.012" down in a 9.600 deck, they weigh less and cost more.
It's your dollar.

R.

We picked them up today. They will be an improvement over the stock heads. I plan on just doing a gasket match and a valve job. I read up on them and the '91 was a bit of an anomaly in that one guy found out that the 714s were listed as Magnum heads but needed LA head gaskets. They are the same head as a 302.

The motor was a roller and did have hollow push rods, with oil in them, even though it had LA rocker shafts. Interesting.

Believe it or not but one article that I read stated that these Swirl Port heads would out perform the X or J heads due to the better combustion chamber. Even though the valves were smaller. The chamber is 62cc and I plan to check how far the piston is in the hole.

I hadn't planned on doing any more to this motor than a spray can overhaul. But I found an Eddy intake and 600 cfm carb on Craigs and then a buddy had a cam. And now a better set of heads, so here we go.

Thanks

If there are 4 valve releifs they are replacement pistons not factory, you can tell because they have chevy valve placement of the notches. I have torn apart hundreds of 318s and never seen one with 4 valve releifs in factory pistons. That is one big huge myth that needs to go away, just because most replacement pistons have them or even list them for certain years does not mean they came from the factory that way. I currently have 3 short blocks under the bench from 68 70 and 71 and none have valve releifs at all.

As you discovered the 714 is effectively the same as a 302, they ironically came on the 714 casting block also, they changed the casting number for the dakota because it used the bolts on the side of the block for the motor mount. And even stranger is with the changes made for a magnum 318 they also had a 714 casting number. 91 is the only one I have seen with both styles of oiling. The 92 and later magnums had a few early blocks with the hole drilled through the block but never through the head. It is always funny to me how much effort people put into blocking or plugging the passage in the block even though there is no where for the oil to go when the heads are on anyhow.

The 714 or 302 is only better than an X J 596... in a few aplications. They flow the lowest volume of air out of any SB mopar head EVER! Swirl and quench is nice but only trumps air flow up to a very low point in the spectrum of engine builds.

Thanks Dave and everyone for the info. They're worth the few bucks to recondition and we'll get a little more smash than the factory heads. Plus the hardened seats.