RB 413 IS IT WORTH TO BUILD
OK, with all of that said, here's my 413 tale. Back in 1978 I picked up a motorhome 413 for cheap money with low miles because the motorhome burned down around the motor. I thought it was a real good deal. HOWEVER, I found that the motorhome 413 was the industrial\truck version with the cam that ran off of a big gear backwards. No timing chain. Anyway, I tore into the engine and the block was real tight with zero wear and damage. Good? Well... The pistons had massive dishes so compression was like 7:1 or something close to that. They got junked for new standard bore flat top 413 pistons (available from the dealer at that time). The heads were no good so those got tossed for junkyard 440 heads that needed rebuilding. In fact, the only thing that didn't get tossed were the block, crank, rods and a few nuts and bolts. Everything else I had to salvage from junkyard 440's. That included things like the oil pump, timing cover, balancer, flywheel, oil pan, dipstick, pulleys, used intake, new timing chain and proper gears, camshaft, lifters, pushrods, rocker arms, distributor, drive gear, valve covers, water pump, pump housing and a LOT of other stuff to make it work. In the end, I had a nice motor that was down on cubes but if I'd done my homework, I would have passed on it and went for a 440. I still have that motor though.
If I had to do it again, I'd walk away from the 413. If it's free, I'd just use it for parts.
I also notice someone has posted a link to new 413 pistons, BUT, those are the dished low compression industrial\truck motor pistons which means if you use them with the larger chamber 440 heads you're going to be down in the weeds compression wise.
OK, with all of that said, here's my 413 tale. Back in 1978 I picked up a motorhome 413 for cheap money with low miles because the motorhome burned down around the motor. I thought it was a real good deal. HOWEVER, I found that the motorhome 413 was the industrial\truck version with the cam that ran off of a big gear backwards. No timing chain. Anyway, I tore into the engine and the block was real tight with zero wear and damage. Good? Well... The pistons had massive dishes so compression was like 7:1 or something close to that. They got junked for new standard bore flat top 413 pistons (available from the dealer at that time). The heads were no good so those got tossed for junkyard 440 heads that needed rebuilding. In fact, the only thing that didn't get tossed were the block, crank, rods and a few nuts and bolts. Everything else I had to salvage from junkyard 440's. That included things like the oil pump, timing cover, balancer, flywheel, oil pan, dipstick, pulleys, used intake, new timing chain and proper gears, camshaft, lifters, pushrods, rocker arms, distributor, drive gear, valve covers, water pump, pump housing and a LOT of other stuff to make it work. In the end, I had a nice motor that was down on cubes but if I'd done my homework, I would have passed on it and went for a 440. I still have that motor though.
If I had to do it again, I'd walk away from the 413. If it's free, I'd just use it for parts.
I also notice someone has posted a link to new 413 pistons, BUT, those are the dished low compression industrial\truck motor pistons which means if you use them with the larger chamber 440 heads you're going to be down in the weeds compression wise.