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Engine and Trans R&R

Discussion in 'Vans' started by FLynes, Jun 27, 2017.

  1. FLynes

    FLynes New Member

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    Hi all,

    Last year I purchase a 1976 Monaco Class C motorhome, built on a 1975 Dodge MB300. Although the 360 2bbl only had 58,000 miles, I wanted to pull the engine and freshen it up. Years ago I had a 1973 Fireball Class C built on a 1972 MB300 chassis, and the nylon timing gear gave up the ghost with little more than 52,000 miles, so I wanted to upgrade some of the components and have a reliable lump that would give us years of fun.

    When I pulled the heads, my eye caught a visible casting flaw between the #5 & #7 cylinders, and I'm amazed that the head gasket never blew. At this point, I knew I was in for a rebuild. When I started doing my research, I found that buying a reman'd 360 would be cheaper than having mine machined. I bought a reman'd 360, bored .030" over, from a seller on eBay for $1595, no core charge, free shipping and a 5yr/unlimited mile warranty. The seller also let me pick my own camshaft, so I went with a Mopar Performance camshaft P4452759AE. My understanding is that this cam closely resembles the cam that was in the 340 and what Mopar used in the A58 360 police engine. When I ran the numbers on the desktop dyno, it gives great torque through 3500RPM.

    This last weekend I finally pulled the old block and dropped the A727 LoadFlite. Since I have a reman'd engine, I might as well have the tranny rebuilt, so that everything is new. I'm also going to install new motor mounts, trans mount and rubber suspension bushings while I'm in there.

    Here are some pics of my work so far. If you guys have any suggestions, I'm all ears. It's been years, since I've tackled a job of this size.
     

    Attached Files:

    valiant67 and Devildodge like this.
  2. FLynes

    FLynes New Member

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    In my above post, I meant to type E58, not A58. Sometimes I type too fast, and sometimes my Lenovo laptop doesn't type the letter I press, so apologies in advance....just now caught the error, and Allpar doesn't have a permanent "Edit" feature that I've found.
     
  3. valiant67

    valiant67 Rich Corinthian Leather
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    The early E58 may have had a decent cam (when it was the replacement performance motor for the 340, long before it was a common police motor), later E58 motors had a very mild cam.
     
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  4. pt006

    pt006 Active Member

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    The cam seems a little too much for an RV with [I'm guessing] low compression. The early 340's had over 10:1 compression ratio.
     
  5. AHBGuru

    AHBGuru Active Member

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    I think the big switch (in cars) was in '78. All the shorter gears (3.55, etc) went away, and the 340 cam wouldn't have worked as well as the 4.10/4.10 stick used on the later E58.
    By 1981, the 4bbl squads were all at 2.94 out back, but they did keep the 4.10 cam on the E48/ELE 318 through '89.
     
  6. FLynes

    FLynes New Member

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    You are correct. Originally, the 360 in our RV was 8.0:1 compression. When I had the reman'd engine built, I had them bump it up to 9.0:1. The desktop dyno, while not 100% accurate, gives me a ball park estimate. I'm attaching a pic of the dyno results.

    Our motorhome has 4.10:1 rear gears. With the .430/.450 lift and the 260/268 duration (221/228 @ .050), I should have some very good pulling power....I hope. We'll see.
     

    Attached Files:

  7. dana44

    Ad-Free Member

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    Yeah, this was a good cam selection for a 9:1 engine that will be running highway speeds right around 3000rpm most of the time.
     
  8. Bearhawke

    Bearhawke Things happen for a reason

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    1968-73 340 pretty much used the same cam; the 1968 4 spd cars did get a slightly hotter 'shaft and I believe the 1970 340-6 pak also received a hotter cam. 1974 360-4V HP used the old 340 cam as did the 1975-76 Federal (dual exhaust non catalyst) 360-4V. The 1978 Lil Red Express truck was the final year that got that hotter stick. All of the other 360's; regardless of carburetion and/or exhaust, got the '360-2V' camshaft.
     

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