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Pulling a 360 out of a Motorhome. Now what?

Plymouth71

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Hey everyone, I have been a member for years, and I appreciate all the advice and opinions expressed herein. I have a 1971 Plymouth Satellite with the original 318, 904 with 8¼ rear end. Not sure what gearing I have but I know it's not a sure grip and it doesn't scream on the highway (yet) . I have added 2¼ dual exhaust mounting to the original manifolds.
I had been looking for a big block, but they are scarce in my area, commanding big $$. I've decided that I don't want the hassle of tracking down parts to convert it a big block, and have purchased a 1975 360 out of a Motorhome. I have limited information on the motor, except the odometer reads a little over 71k miles, and that it was supposedly rebuilt with a 4bbl (vin shows a 2bbl) and has a cam(unknown origin/type) and long tube headers. I will be removing it from the vehicle this weekend. It runs( very smooth) and drives, and I believe it comes with a 727, but I did not verify.

I'm not sure if I want to just clean it up and put it in the car or perform some upgrades. Money is tight right now but I do have a 1972 340 intake with Thermo quad I could put on. I'm in no rush to install the 360, as the 318 runs fine, but if the 360 has Infact been rebuilt, I wouldn't want to do it over again.
What can I look for to determine if it has been apart, and what cam is in it?
Any other things I should consider? I'd like to look at a sure grip or aftermarket rear diff set up with a little more gearing for more fun, but still reasonable on the hwy. There are lots of great summer car shows within an hour's drive of me.

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Do a compression test.

Check how much vacuum it has at idle, is the gauge steady or fluttering? Now adjust the carb with the vacuum gauge on it and set for maximum vacuum.

Check how tight or loos the timing chain is. Remove distributor cap. Get you breaker bar with a 1 1/4" socket on the balancer bolt. Have a helper look at distributor rotor and watching you turn the engine one way, then the other and see how far the bar moves before the rotor start turning the other way. This will be a bit difficult on the van/motorhome. Will be easier with the plugs out from the compression test.

Remove distributor and look inside the engine to see if it's clean or has a buildup of deposits or sludge.

Post back with numbers and results.
 
I'd pull a valve cover off as well.
Sometimes the pcv valve can give an indication.
But if it idles smoothly then it's likely an RV cam or something fairly mild.
I would consider swapping to magnum heads which would require a different intake as well.
But it should be a noticeable upgrade from the 318 as is.
 
If you have 2.7 gears then swap those to a 3.23 and it will be a different car without opening the hood.

I bought a 360 fury wagon and it wouldn't get out of it own shadow with the 2.7 gears. It ran good, bad gearing.
 
The 360 out of a truck will have a727. This will require a new drive shaft as it is about 4” longer than the 904. The left 318 motor mount bracket will need to modified as the for/aft distance of the 360 block mounting tabs are different. The converter is probably not ideal. But 360s have a weighted converter. So if you swap you need a special weighted converter of B&M flex plate to use a normal converter. You could retain the 904 but would need a B&M flex plate to keep the balance correct. If it runs smooth and the plugs look good I’d stuff it in. I would replace any seals or gaskets while it was out.
Doug
 
You could pull a spark plug, and stick a bore camera in there, to see if the top of the piston has any oversize marking. Pull the dual diaphragm power brake booster, too. I use them for disc brake conversions, because they are easy to get at, without crawling under a car dashboard to undo mounting bolts.
 
Not sure if the Van oil pan is different from a car, most likely and your 318 pan won't fit the 360.
 
The truck engine has or should have a 6 qt pan. May have a low stall converter, paper tag on converter say so, unless it's been replaced. Really big difference in a stock replacement converter. My van was a '78. Stage 3 truck 360, 2 barrel, regular leaded gas. Look at the gas tank filler, large hole or small hole. Large is leaded, small is no lead. My timing chain (nylon aluminum) was ready to go when overhauled. If that engine was gone through, maybe they put a steel set back in.
 
Not sure if the Van oil pan is different from a car, most likely and your 318 pan won't fit the 360.

Yes you'll need a 360 car pan, pickup and dipstick.
The pans are definitely different. I've been thinking of upgrading my 318, in my '75 Trademan, to a 360/stroker, but the RV swap seems like a good option. Thanks P71, for the idea on this, I'll be looking around now !!!
 
Ok! It has been removed. Unfortunately I had to leave the party and head to my real job while my Best Friend and our boys finished the removal. I'll probably take a closer look tomorrow and update you on what I find.

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Likely good internals in the 727, unfortunately you would need to swap the tailshaft and housing to work in a car, not a big deal but just a detail that would have to be tended too. Your intake and TQ would be a worthy swap. As above, check for timing chain wear for sure and a compression test would be nice and is still doable on the floor although cold results will be lower.
 
Likely good internals in the 727, unfortunately you would need to swap the tailshaft and housing to work in a car, not a big deal but just a detail that would have to be tended too. Your intake and TQ would be a worthy swap. As above, check for timing chain wear for sure and a compression test would be nice and is still doable on the floor although cold results will be lower.
I would bet being this motor home is a van based chassis. That it has a standard tail shaft and housing.
Doug
 
Hmmm... Me, I'd get a set of aluminum aftermarket heads for the 318, and install the intake & TQ, maybe a set of headers on the 318.
 
Uhhh....

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You covered the dude's face? Is he in the witness protection program or something?
 
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