I have a low millage dodge 318 out of a 1974
duster it was rebuilt 6 months ago.

I am putting it in a truck but want to put
a 4 barell intake on it and newer exhaust
manifolds

I need info on what is possible I really
dont want to change the heads If I dont
have to.

I was told that I might have problems with
water pasage ways on the intake ?
and exhaust ports wont match ???

THANKS any info or ideas or specific parts I could make work would be great.

get a 4bbl intake and bolt it on.:D

the 318's intake and exhaust ports are smaller than the 340/360 heads, but you wont notice the 4bbl intakes bigger ports.;)

Edelbrock performer has small intake ports that will match up to your heads perfectly; best intake choice IMO, and a Qjet will bolt on directly. Putting a newer ('87-up) set of exhaust manifolds on does give some misalignment but the effect is mainly on the floor of the port and acts as an anti-reversion dam. DO NOT gasket-match the manifold to the head at the floor of the exhaust port; Bob Mullen (among others) used to braze up the port floor because of the retrograde flow in this area on stock heads of that vintage. You don't need to change the heads to run a 4bbl; but you can get more hp out of it by doing so.

340/360 heads (X and J castings) have big ports with 2.02/1.60 valves and flow better than the early stock 318 heads. However, this also has the effect of moving the powerband way up, since a 318 won't keep port velocity up at low rpm with those heads; driveability and low end suffers. They also have larger combustion chambers which kills the already-low compression of these engines. While it's been popular with the street-rod bunch for a while it really only helps at high rpm, hurts at lower rpm, and is a really poor combination of parts for a truck.

About a year ago I read everything I could find on small Chrysler heads and talked with anyone I could find that had info to share. For various reasons I ended up getting a set of 4323302 heads for mine, and doing a port job on them. These are swirl-port heads from an '88 truck; they have small ports and valves, a 62cc closed heart-shaped combustion chamber; with a thin head gasket this yields about 9.5:1. http://www.pirate4x4.com/forum/showthread.php?s=&threadid=76344 Together with the 4bbl, headers and a '759 cam they get 300hp/350lb-ft out of my old 318 with substantial gains across the entire rpm band - double factory hp WITH low-end improvement. This has proven to be an outstanding combination and I'm very happy with it. At least until I get the 4" stroker crank, etc; but that may be some time off. ;) Those heads with a '761 cam will make 330 hp out of a 318; but then again the powerband is moved higher than I wanted it for a truck, and the altitude here made me want to use a smaller cam because of the lost column density.

thanks for the advise I bought a performer
manifold off e-bay for 150$

can you elaberate more on how to make the exhaust
ports seal better against the newer exhaust manifolds.

I am shurer the manifolds that I will be useing
are not 87 or newer,

the bolts line up but the ports are off
and it looks like I might have problems
sealing them.

any further sugestions would be great
thanks.

$150 for a performer intake? isnt that what they cost new?

Prior to about '87 the exhaust port geometry on LA heads was all pretty much the same. What exhaust manifolds do you have? Are they center-dump or rear? Any idea what they're from? If you're set on running manifolds you want the left side from a 340 A-body or similar, and a right side Magnum for best flow. All the manifolds line up poorly with the ports, but I've never had any trouble with sealing if they're flat and not broken. None really flow all that well and the good ones always seem to be scarfed up by racing classes that require iron manifolds. Depending on what the engine is in (or going into) I'd either get a set of shorty or full-length headers and work with them instead. Sanderson makes a set of shorty center-dumps if that's what you need; there's a bunch of different rear-dump options.

Fel-Pro also has a metallic-composition exhaust manifold gasket that I've never seen leak or fail. Some are open between the center ports (matching center-dump truck manifolds) and others aren't. Find one that fits properly and you should be good to go.

jegs and sumit sell manifold for $220


can find them used for 75$

the one I bought is on the high end but
looks brand new,