Classic Winnebagos & Vintage RVs

Sent: 10/7/2005 8:53 PM

Whats the diff between the 440-1 and the 440-3?

Sent: 10/8/2005 12:35 AM

We've told one of our members, that the 440-3 gets 3 mpg better gas mileage, ....and she believes us.....so don't tell her....and if anyone asks...that's what you telll them....

actually the major difference is the water ports in the block....the 440-3 is the heavier duty truck engine with much larger water ports in the block.....I also believe there is a diffence in the crank shaft...other than that, it's pretty much the same.....

Timmy

Sent: 10/8/2005 8:15 AM

The Chrysler training tech pub I have also mentions "better quality bearings", heads with "induction hardened valve seats", stellite faced valves.... and other minor differences which they dont specify.

I believe they also had water pumps with more blades on the impeller, and a "skirted" thermostat that looks different from the trucks/vans. The radiator was larger than on the vans and pickups.
I believe the exhaust manifolds were different.
The heads being different is a cause of confusion, since the spark plugs were different in the pickup/van heads from the heavier duty engine heads. Not just a different heat range, but for some model years, a different type of plug seat - the tapered seat instead of the flat seat with washer. So try to take one of your old plugs with you when you go after new ones.

Does anyone know if the pistons in the 440 were cast, or were forged?

You are correct on all counts, denisondc.

The 440-3 was the "Heavy Duty" engine of the series... generally more torque and less horsepower than the car-engine 440-1.  Pistons in the 440-3 are fancy cast aluminum ("autothermic" = inserts to control piston skirt expansion; at least from '76 on), while production 440-1 pistons are plain cast aluminum. The 440-3 also has a lower compression ratio (about 8.1:1 for '76 and later).

Other notable differences in the 440-3 are:
   

   
• Rotating exhaust valves - supposed to help prevent 'burned valves' - under high rpm and heavy load conditions.
• Heavy duty connecting rods (thru '74, even up thru '77 in some cases) - like in the 440 Six-Pack and other High Performance engines.
• Heavy duty block casting - extra reinforcement ribs, etc.
• Heads have extra cooling passages, so require a special head gasket
• Special 'skirted' thermostat for coolant passage

Good revival of an old post - very useful info!