'68 318 to carbed Magnum 5.2: Check my checklist

At this point, I feel it's safe to put together a list of things one should expect to have to change in the process of doing a Magnum swap, regardless of Mopar platform:

Be prepared to replace and/or acquire:

• Obvious due to being drilled into us in every discussion: Center oil pan and sump.
• Also obvious due to repetition: 360 and 5.9s will require an aftermarket flexplate balanced for the specific engine you are using. LA 360s and 5.9s also use different plates between each other, plus keep in mind the smaller 904 torque converter size vs. the larger 727 when choosing. I won't go into detail, just make sure you look for one that matches the exact engine you have to the exact transmission you have, and beware of torque converters with weights added on them - search the forum for more on this.
• You must get an air injection blockoff plate and matching gasket when using Magnum manifolds with air injection provisions (may not be applicable on A-bodies due to manifold options)
• Be aware of your water pump intake location. Pre-1970 is on the driver's side. If you use 1970+ accessories or a Magnum pump, expect to change your radiator and fan shroud to that of your car's 1970+ bolt-in equivalent.
• Magnum water outlets are offset to the passenger's side. You may have to get creative locating an upper radiator hose for your particular application.
• Engine mount ears are as I mentioned earlier. Order yourself some longer, grade 8 mounting bolts in advance, or you'll use the ones from your starter and bellhousing, then wonder where the hell they went when you've got the engine lined up (I'll post the bolt length here soon as I'm under the hood again).
• Transmission linkages and cables from the Magnum donor 46RH/RE trans have to be transplanted onto your 904 or 727 for the MPFI setups. I think. Don't go in here blind; research up before you go to the junkyard to save yourself a trip.
• Your choice, but it's the perfect time to put in a 3.9L Magnum timing chain tensioner along with a roller chain in your engine, if you don't have either already.
• New head bolts if you're putting Magnum heads on a roller LA to make a Maglay 318/360 (such as what I did).
• If your Magnum engine came from a van, probably a new dipstick.
• If your Magnum engine did not come from a van, a Ram Van power steering bracket, provided you maintain a serpentine belt.
• Possibly a longer starter and starter solenoid cable for the mini starter.
• Conventional oil pressure sender or plumbing for your needs.
• Bypass hose nipple. Harder to find than you think. Don't forget bypass hose.
• The transmission-to-engine braces are 9" long on most older engines. 360's became 10" on the left side in 1976, 318's were increased the same 10" in 1981 (thank you Doug Anderson for the info). To be safe, just make sure you get the braces that were already on your donor engine, because those 10" braces are less common and rarely listed correctly on eBay.

For those of you converting to V-belts from serpentine:

• Mechanical fuel pumps are only possible with snout extenders on Magnum cams. If you find a roller-cam LA, chances are you'll have a long cam out of the box. If you plan on changing the cam on your Magnum, Lunati is one of the few companies that will listen to you when you ask for a grind to fit a Magnum block, but using a core with the long LA snout.
• If you use an electric fuel pump, a blockoff plate IS available for the LA timing cover.
• LA timing covers prior to 1970 have timing marks on the passenger's side or no timing marks and a bolt-on steel indicator. Keep this in mind, as your Magnum will be marked on the driver's side.
• Power steering brackets for '70+ cars are completely different from 1969 and earlier due to the omission of the extra "ears" on the later water pumps. Your alternator bracket may be slightly different as well.
• If you swap to a Saginaw pump from a Federal, be aware of different steering box fittings when ordering your hose. Pre-1969 cars used 1/4" NPT to the hose, 1969+ use 5/16 NPT, and the box itself is 1/2"-20tpi SAE with a crush washer. Various Mopar suppliers sell the alternate fitting.
• Again, be aware of your water pump intake location. If you swap the offset, you obligate yourself to a replacement radiator. Most of these radiators are semi one-size-fits-all, and may require a different shroud and upper radiator hose (my aftermarket, Chinese KKS B-body compatible radiator is patterned after an M-body radiator, and is thus about 1-1/2" squatter than the original. It required an M-body upper radiator hose which kinks down to make up for the loss in height over the original radiator. If you've got a 26" radiator swap going in your A-body, your experience may be similar to mine).
• On that note, make sure your brackets for either Saginaw or Federal match the era of the water pump, or you could be trying to mount an early bracket into thin air on a later water pump.
• 1970-style, fixed lower alternator brackets will bolt to the water pump, but the bracket to the back will interfere with the Magnum head. You'll have to cut the bracket and weld it up.
• Think out your arrangement for air conditioning in advance. If you have a 4-groove pulley like mine (in which case, you probably have a roller LA), you may find that most aftermarket setups are designed to work with 3-pulley systems found on pre-roller engines.

For carbureted conversions, add the following to the above list:

• Intake manifold; make special note of thermostat outlet location and water bypass angle. Some M1 manifolds are set up for straight-out bypass hoses for use with Magnum water pumps (and thus the factory serpentine system), others are angled to meet up with LA pumps.
• Magnum manifold alternate throttle bracket for 4-barrel applications, P4876314. Allows original hardware to be mounted on straight-up style Magnum intake bolt bosses.
• Think out your ignition system in advance. Staying with Mopar electronic ignition? HEI? Your coil and ballast resistor may change or require modification with HEI. Read up on it so it doesn't slow you down needlessly.
• Mopar connections on your carb. Just saying.

And of course, visit http://www.magnumswap.com/ before even reading through my list, because they cover some little bits that I haven't up here.

Might be more, but I can't think at midnight anymore.

-Kurt