440 from an rv... anything different?

I tried to search the forum on this but didn't find anything...

It seems that I read in the past of differences in 440's used in RVs or motor homes. Can you guys tell me what the differences are? Any specific P/Ns to avoid?
I would just be looking to put it aside as a spare block and crank (maybe heads and misc.). Thanks!

RV specific heads are different,and not worth saving for any muscle car application.
They have extra water jackets where the Water pump housing matches up with the heads and also not worth saving.
They also have angled spark plug holes,FYI and different exhaust manifolds,too.
Mid-late 70's blocks have a higher nickle content and thicker cylinder walls which is good.
Made for torque,compression is anemic and the pistons do sit way down in the hole.
Cranks will do fine but just need the typical balancing to match new pistons,etc.
Hope this helps

Block and rotating assembly are the same. Sometimes heads are different. I know some industrial big blocks came with the RV heads that had extra cooling passages and took a special, heavy water pump housing. I can't remember if that applied to 440's or just 413's. Someone here will chime in. But either way the block would still make for a good spare.

I don't know of any differences, but a buddy of mine has two and both have huge radius's cut at the top of the cylinders. None of the car 440's I've owned had this.

Iv hade a couple of motor home 440s & none of them hade the truck type water pump housing bolted & plumed to the cyl.heads or angled plugs,they hade the 5/8 plugs with the extra coolant holes around the plugs,6 pack type rods & double roller timing chains.I think it depends what type/weight class of chassis the RV was built on ?

If you have the heads with the small spark plugs, they have the extra cooling holes. They need to be used with the block that has the holes to match them. I’ve had trouble with two different blocks that came from motor homes and had these holes and I did not have those correct heads to match. They run hot on a hot day in a Texas summer.

Correct...

(I've got a set of heads...3751213...

The water jackets matched...


Scrapped the block...

Mopar made two different versions of the 440 "motorhome" motors, regular and the 440-3 H.D. version which has the extra cooling holes already mentioned. The first year (1973)mopar used the 440 motor home motors usally had the bigger, thicker, six pack rods, and forged steel crankshafts I'm not sure which year had those rods and exactly which year they switched away from then to the standard type 440 rods found in the later years
The later years had the external balancer and matching weighted converters
Before deciding to use any old motor parts have them thoroughly examined by a good competent machine for cracks, wear and other things like a good sonic test to see how far you can safely bore the blocks

I noticed this as well on the RV/Industrial block I have. Other oddball thing about this block is it's bored as a 413 and has a '78 casting date. 413 production supposedly ended in '77.

Wow....this is all over the place. I have a 73 440 motor home short block in my car now. It came with big rods & the extra holes in the block deck, but I don't have the motor home heads, so they're blocked off & I've never had a leak or anything. The standard head gasket blocks those holes.

I've "heard" that the heads are just fine, that if you have the motor home heads you can drill two holes per cylinder in the deck and turn it into a motor home block (basically) to work with the heads, and that they cam with the big rods but lighter pistons so you could use a neutral balance harmonic balancer. I only bought the short block without the balancer and put on the offset weight balancer...but balanced my motor anyway, so might have wasted money hunting down a six pack balancer. I've also heard you can drill holes in standard head gaskets for the motor home head/block combo.

Both of my experiences with the MH blocks were similar. One was a bud of mine. He bought one from the local yard and installed 906 heads on it. Could not keep it off 230 degrees. Changed the block and left everything else the same and ran cool. Mine was an NOS short block I bought when MoPar was giving stuff away practically. It was a cast crank std rod motor. It was in a tow vehicle with 906 heads. It ran hot and would vapor lock all the time. Finally gave up on it and the 400 back in the truck and sold it. They were both 76 or 77 castings. I final bought a 78 broke motor home long block with correct heads and they are on my motor now. It runs fine.

might be some info for you here
http://www.440source.com/blockinfo.htm

Ok, from what I remember working at the Dodge place. Early 70s the engines where cooking the heads-ex valves from the extra load. To fix this Chrysler made new heads (basically 452 heads) with the small sparkplug and two holes to help cool the valve, nothing exotic, standard new blocks where just drilled and older blocks-gasket where also drilled when retrofitted with new heads.
You can use regular heads on the MH block and MH heads on any block. I have in my possession a big rod- extra holes block with no chamfer at the top, straight out of a MH. Industrial engine is a whole nuther ball game, but a very strong block and very thick bore walls.
Steel crank and block is worth getting.