340 or 360???

Since you've decided on a 360, it would benefit you, I think, to look at the advantages of the L-A vs. Magnum motors, and vice-versa.

The Magnums were introduced in 1992 or '93 (can't remember), so they've been around for at least sixteen years... plenty long enough for the junk-yards to be full of them. That brings the price down.

The two engines are very similar in most respects, but there are some parts that were changed when the Magnum version came out that bear mentioning.

The lastest-year L-A 360s had roller lifters, beginning in about 1986, I think.... check that out for accuracy. I'm not sure when they started.

With the oil situation being what it is as regards missing ZDDP (zink) in a lot of oil, rollers are a very desirable consideration, since they don't seem to need the missing ZDDP to live a long time. Cam longivity has sometimes been a problem with flat tappet cams since the ZDDP debacle. Magnum 318s and 360s all have roller lifters.

Magnum heads are seen by some as being superior (at least, on the exhaust side) to the best stock L-A heads, but I don't think it's been proven, and when discussed, doesn't seem to be a large improvement in terms of flow. Again, this is arguable. They're not going to flow like an Edelbrock or a W-2.

If you buy a junkyard Magnum engine, in my opinion, you should try to buy it less the intake and fuel injection system. The stock intake manifold is not a very good one, and there are several really good 4-bbl intakes available (Air Gap, etc.) that, along with a 750cfm carb, can replace the electronic fuel injection system and will greatly simplify the installation (no computer necessary.) You'd need an electric fuel pump, or install a pre-Magnum front cover on the engine and add a fuel pump eccentric-extension to the nose of the Magnum cam (available from Hughesengines.com.)

Headers are available for this swap, with everything from the el-cheapo Spitfire model to the expen$ive TTI setup that is a bear to install, but is arguably the best available for this swap, once it's "in."

If you don't want to have to do a major amount of fabrication on the rear mount, then stay away from the 4-speed overdrive automatics. They are great to have, but are a pain in the butt to install because of the physical size of the overdrive unit in the tailshaft. A lot of floor-pan and rear crossmember surgey is required for the install.

If you stick with a 904 or 727 3-speed automatics, everything fits pretty well, as is. There may be some floorpan issues with the 727; I'm not sure about that. A manually-shifted 4-speed is another option, but I hear that clutch linkage can be a bear, with the available headers. Years ago, I built a 340, 4-speed '64 Valiant, but I ran fenderwell headers, so clutch linkage was no problem, then. (Most fun car I ever owned!!!):cheers:

The L-A engine can be a good "buy" because there are literally millions of them out there, but if you get one, my advice would be to try to get one with the 1986-up roller cam setup; you can't easily add a roller cam setup to one that came originally with a flat tappet cam. The lifter bosses in the block are different...

The flex plate or torque converter will have to be specially balanced for the 360 as it will need to have the correct "un-balance" weight, as all 360s are "externally balanced", with the out-of-balance spec being different between the L-A and the Magnum. B & M makes flex plates with the correct amount of imbalance for these engines; just be sure you get the right one, or, you'll have a "shaker."

My car is a ;72 Valiant 4-door, about 300 pounds heavier, I think, than a '65. With a 1998 360 Magnum with only a very mild roller cam and a set of T-A Drag Radials, and a 3.90 gear in back (stock 318 converter) and a Hughes cam, it ran 13.35 @ 102 mph on a 95 degree day at sea level. It was spinning badly, with only a 1.91 50-ft. time. That was with 340 cast exhaust manifolds, running through the mufflers.

It would be no trick at all to drop your '65 into the high 12's with an almost completely stock motor.

You might consider a crate motor... or, not.

Good luck, and keep us posted!!! Early A-Bodies are my personal favorite of all Mopars...