Which heads?

[Frankie]

I am building a mild 318 for my 71 Dart...
I have 2 engine blocks, one is a 71 318 the other is a 69 318.
I have three sets of heads
A set of 302’s from an 86 van engine.
And 2 sets of 675’s on the 71 engine and the 69 engines.

The 71 has adjustable rockers and the 69 has stamped.

I plan on using one of these sets, period.

Opinions and reasons why one is better then the other?

I’m leaning toward the 302’s for a couple of reasons. Not the least of which is the hardened valve seats.

Thoughts, ideas, reasons would be very much appreciated.

Thanks.

 

[krazykuda]

I would use the older heads and have 2.02" intakes and 1.60" exhaust valves with hardened seats put in the exhaust side...

And open up the ports a bit....

Some of the 302's have been found to crack...

 

[mderoy340]

For a mild build run the 302s with the adj rockers.

 

[rumblefish360]

For a mild build run the 302s with the adj rockers.

X’s 2!

All heads can crack, not just the 302’s. The heads should be check for this anyway before building. Along with a sonic check of the block.

The 302 has better exhaust ports. Depending on the level of build, I would send them to Ryan J for a full porting. The head is very capable.

 

[TXDart]

What pistons you using or just overhaul 69 or 71 318?
What Compression you shooting for?
What chamber size are the heads in question may help you decide on which head and cam choice...

 

[Wyrmrider]

do a "straw man" build using the 302'
you can change the intake valve but do not do the exhaust larger as you will go through the hardness]
do some research on those heads as they are different than anything else
you can get more top end HP with other heads but 302 should work very well for a street build
as
TX asked what compression + what gas
and what piston to get good quench at the cr you are shooting for
the exhaust port is better with that head so you do not need the more lift much longer exhaust lobe that used to be popular
your only other reasonable choice is some new EQ of AL
do keep the adj rockers- sell the 675's

 

[Abodybomber]

Frankie ,302 castings... watch the exhaust seats on the crossover port. As you probably know ,the exhaust valves sink ,on those two ports. Porting might not be needed ,obviously.

 

[rumblefish360]

Frankie ,302 castings... watch the exhaust seats on the crossover port. As you probably know ,the exhaust valves sink ,on those two ports. Porting might not be needed ,obviously.

100%!