How To Stock Buildup A 440 Magnum - 440 RestoTo Rad!
How Will You Have That 440?
From the March, 2001 issue of Mopar Muscle
By Steve Dulcich
Photography by Steve Dulcich
It's back to the summer of...
It's back to the summer of '69, with a fresh, factory spec 440 Magnum.
Over the last few months, regular readers of Mopar Muscle were treated to a buildup of a 340, built to stock specs, then wound against the dyno in original trim. With some carefully selected bolt-ons, the simple and straightforward 340 produced nearly 400 hp, gaining more than 110 hp over its tested stock 280 hp. That done, the next logical question was whether it would work with a 440. There was only one way to find out, so we dug into the engine-core pile and plucked out a 440 Magnum powerplant for a stock buildup as well.
Like the 340, the objective was to build the engine as close to stock specs as possible for baseline testing. This makes the parts selection nearly predetermined; OE replacement-type parts would be used throughout, but with the necessary machine work done to ensure as-new performance from the factory package.
Though it was going to be constructed to stock specs, there were some decisions to be made in the final parts selection. Generally these decisions are not centered around power production questions, but fall more into the category of durability. Do we use the cheapest "rebuilder's special" cast-iron piston rings or higher-quality low-wearing moly rings? Economical replacement cast pistons, or the forged version? Standard or high-volume oil pump? Really, in terms of power, the cheaper stuff or the higher quality stuff will not make a difference.
The block was bored .030 inch...
The block was bored .030 inch and decked .020 inch at M&R Machine in Glendale, California. That was it for machine work to the block. The heavy cut on the deck compensated for the thicker-than-stock replacement head gasket.
The real choice centers around the level of durability. The cast pistons may be fine, but while spinning high rpm on the dyno, the forged units provide better peace of mind. Cast pistons can grenade unpredictably, while such failures are much more rare with forged units. Plain iron rings work great, but wear the bores faster over the long haul. Think about the intended use of the engine when selecting parts, especially the internals that can't be readily inspected or changed later.
For this build, all of the components were ordered from PAW, one of the least expensive retail outlets of engine rebuilding parts in the country, and they sell everything required to renew the 440 in a parts package. The basic rebuild kit can be upgraded with higher-quality components at an added cost. For this engine, we only upgraded the parts that served as the backbone for a durable high-performance street engine. PAW's system of offering a basic kit which can be customized by making substitutions or upgrades allows fantastic flexibility for putting together a parts package that meets requirements for a budget or performance specs.
We chose forged TRW #2266 pistons. The TRW #2355 "Six Pack" piston with its taller compression height and valve-clearance notches would have been better for a high-performance rebuild, but the #2266 got the nod because it's the stock replacement piston for the 440 Magnum being duplicated in this build. These pistons have a deck clearance of a whopping .089-inch in a standard block, same as the stockers, which makes us wonder how the factory arrived at its advertised compression ratio specs. Federal Mogul non-file-fit moly rings were selected to go around the pistons, since we wouldn't use anything other than moly in any engine build. We used non-file-fit because no production engine had hand-fitted ring end-gaps.
A high-volume oil pump was chosen in place of the standard piece because the cost of the upgrade was minimal. Since the premise of the build was to begin with a 440 built to stock specs, the cam would have to be the original 440 Magnum piece, still being sold by Mopar Performance. The Mopar Performance cam and lifter package was a substitution for the cam and lifter package included in the PAW kit. Finally, we chose Clevite Tri-Metal replacement bearings, a new steel roller timing chain, and an upgrade to a Felpro gasket set. A set of high-strength Milodon rod bolts were ordered, since this is the most highly-stressed fastener in the engine. The rest of the old stock bolts would be cleaned and reused.
Also on the list at the machine...
Also on the list at the machine shop was a simple valve job to the heads, along with hard exhaust inserts for today's unleaded fuel. Guides checked out adequate, and the original stock valves were retained.
From here it's back home for...
From here it's back home for assembly. Nothing trick allowed; this engine will go back together to factory '69 specs. After laying in the top half of the rear seal (lube the lip), the bearings and crank go in. M&R reground the stock crank .010 inch to standard undersize dimensions. Stock main-cap bolts were reused and torqued to 85 lbs/ft with two side packing strips.
The top half of the rear main...
The top half of the rear main seal is retained in an aluminum housing, which seals to the side of the block with two side packing strips.
Though the rings were pre-gapped,...
Though the rings were pre-gapped, we did a spot check to see how wide the gaps were, showing .022 inch top and second. That's considerably wider than a custom-filed ring gap; but for this production-style build, this engine wouldn't get any custom massaged or fitted components.
Stock replacement flat top...
Stock replacement flat top TRW #2266 pistons were used, since these are dimensionally equivalent to the production 440 Magnum pistons. Deck clearance was .069 inch after surfacing the block enough to compensate for the thicker aftermarket gasket. Had this not been an attempt to duplicate the production Magnum, the taller .070-inch TRW #2355 "Six Pack" pistons would have been used.
Inside, the factory '69 LY...
Inside, the factory '69 LY rods were used, resized by M&R Machine, and fitted with Milodon's high-strength bolts. The Six Pack rods went in 440 Magnum engines in '70, the same year they debuted in the actual 440 Six Pack engines.
Stock as stock is; the cam...
Stock as stock is; the cam is the real deal-a factory 440 Magnum cam, still available through Mopar Performance under part number P4452783. Specs are .450/.458 lift; 268/286 degrees advertised duration with 115 degrees lobe separation. Mopar Performance does not furnish a duration number at .050 inch.
The block and heads were taken to M&R Machine in Glendale, California, for machine work. The block was bored .030-inch over and finish-honed for moly rings. Our gasket kit, like any aftermarket replacement set, comes with a composition gasket; they have a compressed thickness of .040 inch, while stock 440s came with a steel-shim gasket of about .020 inch. This costs compression, so the block was decked .020 inch to compensate, bringing the final deck clearance back to stock specs with the composition gasket installed. Had this engine been built without trying to duplicate actual production specs, the block would have been decked considerably more with these pistons.
Our stock '69 LY rods (the heavy "Six Pack" rod didn't debut in the 440 until 1970) were fitted with Milodon rod bolts and resized on the big ends. The factory forged crank was ground .010-inch under on the rods and mains, completing the bottom-end machining.
Taking care of the top-end, a set of factory correct -906 castings were prepped by M&R Machine. The heads received a basic valve job, retaining the original factory valves. To survive under hard street use with unleaded, a set of hardened exhaust inserts were installed. The valve guides checked OK.
All in all, a resto-type 440 such as this was simple and inexpensive to build. The actual engine assembly is straightforward, requiring none of the custom massaging usually needed in a high-output mill. Beginners should have a factory service manual on hand, which can be purchased new from Year One. The photo captions detail how this one was put together in one day, once all of the required parts were cleaned and painted.
The 440 Magnum
The 440 was undoubtedly one of the most respected engines of the musclecar era, not for screaming horsepower, but for big-time torque at lower speeds. Looking inside, what's really good? The best bore/stroke ratio of any domestic big-block V8 with its 4.32-inch bore and 3.75-inch stroke. Unlike many other big-blocks, the 440's long rods and short stroke make for an optimal rod ratio as well, with high output and street durability. The basic B/RB bottom end, particularly the earlier forged crank type, is extremely durable; in our experience, generally safe to 6500 rpm+ in factory form. In fact, practically any of the production systems, from the lubrication to the valvetrain, were capable of working well in a high-performance application, without the major modifications required with some other engine types. The piston/rod bobweight is quite high, but this is irrelevant in a street performance situation.
Looking at the factory valvetrain, the stamped steel rockers seem unsophisticated; but the system is durable while being lightweight. Less weight in the valvetrain really counts at higher rpm, especially with hydraulic cams running moderate "street" spring loads. The time to give the factory valvetrain the ax is when an adjustable valvetrain is required, or when high lift necessitates a roller-tipped rocker to reduce side loading the valves, which can lead to valveguide durability problems (conservatively .500-inch+ valve lift). For hydraulic cams under .500-inch lift, don't expect big power gains by going to a more exotic valvetrain; the factory stuff works.
The most benefit is in the breathing area, particularly in the heads. It takes a great deal of air to fully feed 440 cubic inches of engine. Unlock the head flow, and the output can go from good to phenomenal. In our 340 test, the production heads were retained throughout the modification sequence. However, the 340 has outstanding cylinder-head airflow per cubic inch displacement for a production wedge head. On the 440, the temptation is to make an aftermarket or modified production head part of the modification plan. Headers and induction changes will be tried on the dyno to see what their influence would be on an otherwise stock engine.
The cam was installed at the...
The cam was installed at the recommended installed centerline of 113 degrees, or 2-degrees advanced. Actually, it landed right on specs just by aligning the timing marks
With the cam and drive in...
With the cam and drive in place, the timing cover was installed. The cover serves as the front portion of the oil-pan rail, and must be installed before the bottom can be buttoned up. Make sure the oil slinger is installed and the two front oil-gallery plugs are in place before the cover closes off the front of the engine.
The damper is best installed...
The damper is best installed with a proper installation tool instead of the hammer-and-crank-bolt method which can damage the crank's threads. This tool was homemade with some threaded rod, a couple of nuts and some welding.
With the timing case done,...
With the timing case done, the pan can seal off the bottom end. The windage tray is an original 440 Magnum piece, available new under part #P4120998. The oil pickup is the production 440 Magnum 3/8-inch NPT piece. Though the larger 11/42-inch Hemi pickup is a popular upgrade, the 440 piece is more than fat enough for most street applications. The sump is an original 440 Magnum example, also available new from Mopar Performance #P4529884.
The damper for this 440 was...
The damper for this 440 was the factory original unit. The elastomer was still good, but the nose was worn by the seal. A Felpro repair sleeve was pressed on to give the seal a new surface to ride on.
A PAW high-volume pump completed...
A PAW high-volume pump completed the otherwise bone-stock lubrication system, since it was a very inexpensive upgrade.
What will this stock spec 440 put out? The factory rating of 375 hp is claimed to be optimistic by many sources, including Chrysler, with the consensus more like 350 hp. For now we're not making any predictions-the dyno will tell the story next month, and we'll all see.-Steve Dulcich
Back up front, the factory...
Back up front, the factory water pump housing was filled with a remanufactured stock water pump from Pep Boys. The water pump bolts strike water, and need thread-sealant to prevent seepage.
Stock -906 heads with the...
Stock -906 heads with the factory original 2.08-inch intake and 1.74-inch exhaust valves are torqued to 70 lb/ft reusing the original bolts. The stock heads will probably be the biggest hurdle to making lots of power.
Dressing out the heads is...
Dressing out the heads is the stock valvetrain, just as it came off the original engine, but cleaned up. This stuff works well with moderate hydraulic cams.
The distributor drive gear...
The distributor drive gear is easiest to install before the intake goes on, indexed to align the slot with the crank centerline (as shown) at TDC. A new bushing should go in the block below it (see your service manual for info on sizing the bushing if required). The original drive was reused, though from time to time these fail under performance use by shearing at the pump, and losing oil pressure. For this engine, we'll risk it. Mopar Performance has a stronger drive-P3571071.
Spanning the heads is the...
Spanning the heads is the factory '69 440 Manifold, used on the Magnum engine, casting #2806178.
The only concession to modern...
The only concession to modern realities is the use of an electronic-ignition distributor. Though this one is a production unit from a later 440 application, the electronic setup is available complete from Mopar Performance, part #P3690428 (RB application). We have a factory 440 Magnum dual point sitting on the shelf, but for the sake of consistent and reliable dyno service, the electronic will be used, even for the baseline.
The icing on the cake: an...
The icing on the cake: an authentic set of production 440 Magnum exhaust manifolds. Swoopy, but how will they stack up against headers? From here, it's only a matter of a few plugs, grommets, and fittings, and the 440 will get a chance to flex its muscle on the dyno.
A large-bore original 440...
A large-bore original 440 Magnum AVS carb tops the manifold, and the valvetrain is covered with a set of stock valvecovers for that resto look.