LA head question.

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AdamR

AdamR

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I just picked up a bunch of 360 stuff. Included was a set of 4343474 casting heads. A quick search sow them as 85-89 318 4bbl/360 heads. Are these the same castings as the 308s ?
 
302 heads are closed chamber the 308 (360 heads) are open chamber.
 
Right, these are open chambered but Ive never heard of this casting before.
 
I'm not sure they share the exh port of the 308s but I wouldn't think they arenything bad either. Just nothing special.
 
Are you sure they aren't 974?

576 is an over the counter only version of the 308.
 
Locomotion said:
Are you sure they aren't 974?

576 is an over the counter only version of the 308.
Click to expand...

No they are 4343475 off a 86 360. I googled them and came up with a few hits that said they were the same as the 308s which is why I asked.

The motor is a non roller block, 360 4bbl with a Q-Jet. My old 69 Barracuda had the 576s on it. Never knew what they were till I sold the motor.
 
If you read the MP engine book, Larry Shepard talks about the early 70s heads such as the J heads and the like. He said they were swirl port heads long before any were advertised as such. I don't think there's a real big difference between the early and late heads. They are all open chamber (except the 302 and magnum) they all had 1.88 intake valves (except the earlier 340 heads and the 318 heads). The ports look the same to the naked eye. I say if the heads you have Adam are open chamber with the 1.88 intake valve, they are good as any of the rest. Probably a good head.
 
Yeah they will work for what Im doing either way., which is basically a stock motor with good machine work and a few small upgrades.
 
I was wondering where you were getting your casting number info for 85-89.

I have a 318 with a 4 barrel intake that looks like it was born there, that I'm trying to identify.

All the casting number info I can find on the web either stops at 1974 or 1979.
 
Rusty are you trying to one up me on "don't F with me" cat avatars?
 
YY1 said:
I was wondering where you were getting your casting number info for 85-89.

I have a 318 with a 4 barrel intake that looks like it was born there, that I'm trying to identify.

All the casting number info I can find on the web either stops at 1974 or 1979.
Click to expand...

I googled the casting number.
 
The 308s were after the heads you have now, just before the change over to the magnum stuff. The 308 is arguabley the best factory LA head they made,with room for improvement just like any other head...
 
I would love to see flow comparison between the 308 and say a J head.
 
My understanding is that the exhaust port in the 308 is the strong point...intake ports look really skinny.
 
Measure the pushrod hole. The 308 will have PR hole that is a little over 5/8". The earlier heads have a 1/2" PR hole. This would be an indicator IMO.
 
skrews said:
Measure the pushrod hole. The 308 will have PR hole that is a little over 5/8". The earlier heads have a 1/2" PR hole. This would be an indicator IMO.
Click to expand...
The 308 casting date is a indicator too, but yes the pushrod holes are pretty large, due to the fact that they were on, IIRC 90-92 roller cam 360s
 
Adam, what site gave you that info.

Is it just a head page?

I've "googled" my intake casting and my block casting and ... nada.
 
AdamR said:
I just picked up a bunch of 360 stuff. Included was a set of 4343474 casting heads. A quick search sow them as 85-89 318 4bbl/360 heads. Are these the same castings as the 308s ?
Click to expand...

If you have the heads...then just look in the int port for the linked over guide boss and stick your finger into the exhaust port and see if its floor is raised/shaped like a mag/308.

The port floor is unmistakable.
I'd say if they were roller heads...the pushrod holes would be a 1/2 inch unlike the Older LA's 3/8 'roughly measured'.
318 heads have a small int guide boss compared to all factory LA 360/340 heads.
 
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