Making Power 318

You can't make power with a 318, they're junk and power is impossible with those. Just kidding! But some guys actually believe that and will convince you to pull the 318 for a 360. That's nonsense, keep the 318 (unless it's bad) and have fun with it.

Before you do anything, listen to Rusty's comment. With a Performer intake and 600 carb it should get down the road just fine, even if it had a stock cam and 318 heads, so you might very well have a tuning issue.

Let's say it's tuned and it has compression and you want more... if you want CHEAP without getting into the rotating assembly, you could get a pair of used Magnum heads and Speedmaster air gap intake. Magnum heads have 1.92" intake valves (318 intake valve is 1.75") and runners that are way bigger than the LA 318 runners. They will also won't hurt compression at all, actually maybe give you a bit more.

Used Magnum heads will be cracked between the valve seats. Don't be alarmed, it won't matter because the cracks don't get into a water jacket and almost never drop a seat because of the cracks. Lots of guys will say that's crazy talk, and maybe it is. But there are tens of thousands of Magnum engines still on the road, many of which have never been apart.

There are 2 caveats with Magnum heads. First, you have to make sure you have lifters that will oil the valvetrain through the pushrods, and hollow pushrods for that same reason. BUT, a 1987 engine would already have a roller cam and roller lifters that allow for pushrod oiling to the valvetrain. You would have to pull a lifter know for sure. I'm not sure if the roller LA engines came with hollow pushrods, but if not just get a set from a Magnum (used, of course).

Second, Magnum heads use a different intake bolt pattern than the LA heads so the Speedmaster air gap makes for a great upgrade at the same time. It is drilled for both the Magnum and LA heads, so if you went back to LA heads you could still use it:

Mopar Chrysler Dodge SB 318 340 360 MidRise Air Intake Manifold Satin