I'm working on a 54 Dodge truck that was modified in the late 60's with a 273. The 273 was a little rusty and already .040 over and I really don't want to spend the cash for a rebuild. I found a low mile 92 318 magnum thats in my budget (cheap) but its fuel injected and I would like to use my edelbrock intake, afb carb, and dual point off the old engine. In manifold listings the 92 and up take a different part no. from the earlier ones. I'm curious as to what the difference is (other than the part no.'s) Can the older intake be used? This is my first Mopar and I'm not familiar with interchangability of the LA 318 and I don't want to screw up. Should I look for an older engine? There's a trans on the engine, I was hoping to use the unit. A pic of the 273 before I pulled it down. Any help would be appreciated, Thanks,Bud
You have a couple of pitfalls you need to look out for. If the 273 is a 64 or 65 then your screwed as far as swapping the intake onto either the magnum or an LA 318. The intake bolt angle is different from the 66-68 273 and all other LA 318s. Quick and dirty way to tell is see what wrench fits the bolts. If a 1/2" fits then it is a 64-65 engine. If 9/16" fits then it is a 66 or later engine. If the 273 is a 66-68 then the intake will interchange with all LA 318s. Swapping a late 273/LA318 intake onto a magnum 318 requires redrilling the bolt angle in the heads to use an LA intake. Hughes engines can do this for you . Heads for all practical purposes are not interchangable due to the way the rockers oil. It can be done but you have to know what your doing. http://www.hughesengines.com/Index/index.php The distributor is a bolt in but you would be better off using an electronic ignition such as a pertronics in an older distributor (aluminum point type) or the iron dual point if available. Be careful swapping the transmission onto the magnum engine or even an LA318. The indexing hub on the center of the torque converter on a 64-65 transmission is smaller then the later hubs so if using the early transmission you would need to change to the later convertor.
jbtine is right on. There are two types of 273 intakes, one that matches the LA engines (later) and one that doesn't. But even if its the LA style manifold, you'll have to deal with the difference in the intake bolt angles. I'd just buy a magnum intake, it'll be a ton easier than having the heads redrilled or the manifold modified, and by the looks of the intake that's on the 273 a newer magnum intake would be a better performer anyway. The 273 isn't without its merits though. It should go .060" over without issue. Egge sells pistons. If nothing else, it should have adjustable rockers and a forged crank, both of which will fit a 318. The rockers will fit all the LA engines. Needless to say, even if you don't build the 273, the adjustable rockers and forged crank are desirable pieces, and would more than pay for a new intake manifold...
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