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460 Big-Block Build - Large And In Charge, Part 1Low-buck, mild modifications for a streetable 460 Ford From the May, 2011 issue of Modified Mustangs & Fords By Richard Holdener
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One of the most effective means of improving horsepower is to increase displacement, and one only need look at the current popularity of 5.0L and 5.8L Windsor strokers to illustrate the performance world’s affection with being large and in charge. We know the Windsor strokers are plenty powerful, but we know too that they aren’t the only motivational game in town. In fact, there are likely less expensive alternatives when looking for a replacement with displacement. Best of all, these cost-effective replacements come from what must be considered humble origins. Take a stroll through the Ford/Lincoln section of your local wrecking yard and, likelier than not, you’ll find a dozen or so big-block Fords just begging for a new home. For now, we’ll dismiss the early 390-428 FE motors and concentrate on the big-boy 460s. Offered also in a slightly smaller 370- and 429ci displacement, the 385-series engines are simultaneously plentiful, powerful, and (best of all) dirt cheap. Pulled from a local wrecking... Pulled from a local wrecking yard, the 460 Lincoln was in excellent shape internally. Recent work had obviously been done, as the heads and cylinder bores looked factory fresh from a recent rebuild. From an enthusiast’s standpoint, the great thing about the 385-series engines is that in addition to the many Ford and Lincoln fullsize vehicles, they also found homes in marine, motor home, and industrial applications. The little-known 370 was used primarily in medium-duty truck applications, but the 429s and later 460s eventually became Ford’s bread and butter big-blocks. Rated at 370 hp in 1970 (375 hp for the Super Cobra Jet), the 429 Cobra Jet and SCJ were the weapons of choice for dragstrips and NASCAR alike. Underrated by Ford, these Cobra Jet motors likely put out more than 400 hp thanks to wilder cam timing, a static compression ratio that exceeded 11.0:1, and a sizable Holley carburetor. Now that we have whet your appetite, forget everything you’ve read about the 429 Cobra Jet and Super Cobra Jet engines, as the supply of those ultra-rare engines has long since dried up. Of course, that doesn’t mean you can’t build something even more powerful, and selecting the larger 460 is a significant step up the proverbial performance ladder. The ’68 460 engine featured... The ’68 460 engine featured dished pistons with valve reliefs. Fear not Ford fans, as the dished piston was necessary to work with the small-chamber heads to create a streetable static compression of 10.5:1. Since the 429 was offered for only a few years, Ford eventually relied on the 460 all through the ’70s, ’80s, and early ’90s to do the heavy lifting. Though never offered in Cobra Jet or Super Cobra Jet guise, the abundance of 460s makes them dirt cheap and easy to come by. Available in wrecking yards, we found a complete engine (including accessories and everything under the air cleaner) available at a local Pick-a-Part for the paltry sum of $265, plus core. For the serious penny pincher, our Pick-a-Part had sale weekends where everything was 50-percent off, meaning a complete running engine was available for as little as $130, plus a core charge of $65. How can you go wrong with a complete running engine that costs less than $200? When you go looking for an engine, especially if you plan on running it as is, make sure to do your homework and thoroughly check out each potentially viable candidate. Since the oil will likely be drained, don’t hesitate to pull a valve cover to check for telltale signs of abuse or neglect. Is there oil sludge present or does the head look clean? Does it look like it might have been rebuilt recently (like ours), or does it look like it spent every inch of those 200,000 miles lugging ore deep in some coal mile? Pull the plugs, check for coolant leaks (stains) and generally give it a thorough inspection (including spinning it over) before making your decision to pull and purchase. We even dropped the oil pan for a quick look. That’s what sealed the deal on our engine, as the 460 obviously had recent work done. Before pulling the engine, we even filled it with oil and fired it up briefly using a battery we brought for just such a purpose.  The reason to choose the early...  The reason to choose the early (pre-’72) engines is that they feature the small-chamber (high-compression) cylinder heads. The heads on our ’68 460 featured C8VE casting numbers.  No Cobra Jet-sized ports here,...  No Cobra Jet-sized ports here, but even these standard heads can be made to flow well with a little work.  Our early heads featured rail...  Our early heads featured rail rockers with guided tips to positively locate the rocker on the valve tip. These heavy rockers are not suited to performance use, as they limit maximum cam lift. The pinch nuts also have a tendency to back off. The one good thing about the 460 heads is that they came equipped with screw-in rocker studs, thus making the swap to guideplates and roller rockers much easier.  [6] When installing roller...  [6] When installing roller rockers on the factory heads, it was necessary to install guideplates to locate the pushrods. The factory 3⁄8-inch studs (on the rocker side) were more than adequate for most cam and valvespring combos, but these are easily swapped over to the larger 7⁄16-inch studs if need be.  Our 460 came equipped with...  Our 460 came equipped with a heavy cast-iron four-barrel intake manifold designed to accept an Autolite carburetor. Using a pair of gaskets on our throttle linkage plate allowed us to successfully run the Holley carburetor in place of the Autolite.  The carburetor that came with...  The carburetor that came with our wrecking yard engine was not usable, so we decided to substitute our trusty Holley 750 HP. The Percy’s Adjust-a-Jet system allowed for easy tuning on the dyno.  The 460 was run on the dyno...  The 460 was run on the dyno using an electronic distributor and manual water pump. The distributor was run with an MSD 6AL ignition amplifier. The factory ignition curve was employed on the electronic distributor (which we pirated from another donor engine in the wrecking yard). The 460 made best power with 37 degrees of total timing.  Rather than run the factory...  Rather than run the factory cast-iron exhaust manifolds, we opted to substitute a set of 1-7⁄8-inch Hooker Super Comp headers feeding a set of 18-inch collector extensions.  Run in baseline trim with...  Run in baseline trim with the Holley carb and Hooker headers, the ’68 460 produced 349 hp at 4,700 rpm and 492 lb-ft at 3,000 rpm. Torque production exceeded 450 lb-ft from 2,500 to 3,900 rpm. Despite the horsepower-inducing, large-bore and short-stroke combination, these 460 Fords make some serious torque.  After our baseline testing,...  After our baseline testing, off came the factory cast-iron intake to make way for the Weiand aluminum intake.  For this mild application,...  For this mild application, we chose a Weiand Stealth intake. The intake swap is a good idea on the weight savings alone, but the intake was also worth extra power. On the dyno, the Weiand intake improved horsepower production by 16 hp, from 349 to 365, but torque production suffered. This is not uncommon on stock intakes, as they were designed to maximize torque production very low in the rev range. The Weiand intake offered as much as 25 hp out past 5,000 rpm, but the cost was a like amount of torque below 3,000 rpm. It all depends on where you want your power production. For a truck application, the low-speed torque offered by the stock intake would be hard to beat, but for any type of performance street application, the additional power offered by the Weiand intake would certainly be welcome.  Next on the to-do list was...  Next on the to-do list was a set of roller rocker arms. These blue aluminum roller rockers from Ford Racing work well as do the more cost-effective die-cast High Energy rockers from Comp Cams. Run with the FRPP 1.73:1 ratio roller rockers, the 460 produced exactly the same power. We’ve seen rocker swaps net 12-15 hp on other applications, but on our mild 460, they didn’t offer any power over the factory rockers. Knowing the factory cam was... Knowing the factory cam was not designed for performance use, we installed this XE262H hydraulic flat-tappet cam from Comp Cams. Certainly mild for a big-block, the XE262H offered a 0.513/0.520 lift split, a 218/224 duration split, and a 110-degree lobe separation angle. Chances are your 460 will be equipped with standard cylinder heads, but there are variations of the standard 429/460 heads that are more desirable than others when it comes to modifications. Though they can be made to thump out pretty decent torque, the later ’88-up EFI 460s should be avoided in favor of the early carbureted variety. Within the carbureted contingent, the early (pre-’72) engine (both 429 and 460s) featured cylinder heads with smaller (74- to 77cc’s) combustion chambers versus 90 cc’s for the later heads. Not surprisingly, the pre-’72 engines offered additional performance even in stock form thanks to higher compression ratios (10.5:1 versus 8.5:1). Early 460s were rated at 365 hp (remember the 429 Super Cobra Jet was rated only 10 hp higher), while the power output of the ’72 460 plummeted to just 212 hp. Some of the power difference between the ’70 and ’72 engines can be attributed to the change from gross to net power ratings. Gross ratings were derived in optimized configuration on the engine dyno before accessories, while net ratings were given in as-delivered tune with accessories (still flywheel rated). Regardless, the early engines with high compression will make more power and everything that follows about the build up of the 460 applies to its little brother, the 429. Installation of the new cam... Installation of the new cam required removal of the water pump and front cover. The base heads (like ours) that you’ll find on an early 429 or 460 will likely feature rail rockers and screw-in rocker studs, along with a 2.07-inch/1.64-inch valve package. This compares to the 2.42-inch/1.72-inch valves used in the Cobra and Super Cobra Jet heads, and slightly smaller 2.19/1.66 in the Police Interceptor heads. A common upgrade for these base heads is to install the Cobra Jet-size valves. When combined with a little porting, these base heads can perform impressively, with 650-700 hp possible on the right combination. It should be noted that the smaller combustion chambers on these early heads make them less sensitive to detonation. Some sources claim that static compression ratios as high as 11.0:1 can be run on pump gas, but this would likely depend on the cam and ignition timing. Run with cold water in a marine application, we can certainly see this as a possibility, but we’d recommend keeping the compression near 10.5:1 for pump gas. The downside to the rail rockers mentioned previously is that they aren’t suited to performance use with higher-lift cams, but since the early heads are equipped with screw-in studs, aluminum roller rockers (and attending guideplates) are an easy swap. Later heads featured positive-stop pedestals for non-adjustable rockers. The factory timing chain was... The factory timing chain was in decent shape, but make sure to check for slop in the chain. Factory timing chains run in ’73-later 460s retarded the cam as much as 8 degrees, so make sure to replace these with a timing chain setup that will allow you to install the cam straight up. All of the base 429 and 460 engines will be topped by a cast-iron intake manifold. Our 4V engine featured an Autolite carburetor, but there were two-barrel versions as well. If you’re going to change the intake and install a mild hydraulic flat-tappet cam, as we did in Part 1 of this 460 buildup, then it matters not which engine you start with as both offered the same compression and cylinder heads. The difference in power rating between the 2V and 4V versions of the 429 was 40 hp. According to our data, the early 460 (ours came from a ’68 Lincoln) was offered only in 4V configuration. The engine had obviously been rebuilt some time in its life, as the bores measured 0.060-over, but there was no work done to the cylinder heads (the valvesprings looked new, but no evidence of any port work). In Part 1 of Large and In Charge, we decided to subject the 460 to some mild performance mods, including a new carb and intake, roller rockers, mildly ported stock heads, and a small flat-tappet cam. We wanted to illustrate a low-buck approach to performance that would combine a low-cost hydraulic flat-tappet cam with porting to the stock head that can be done at home. Look over the captions to see how the 460 faired in Round 1 of its performance buildup. Check back with us next month as we crank up the heat on this 460 with a hotter cam, better heads, and a serious induction system. Is it possible to exceed 600 hp with the stock heads? We’ll let you know next month.  Out came the lifters and factory...  Out came the lifters and factory cam and in went the Comp flat-tappet cam. We made sure to liberally coat the cam with moly-based assembly lube and even ran a bottle of high-zinc break-in lubricant from Lucas Oil. Naturally we installed new lifters from Comp Cams to go with our XE262H camshaft.  Running the new cam with the...  Running the new cam with the stock heads required a valvespring upgrade. We installed the supplied 926-16 valvesprings and 740 retainers, but even this spring upgrade turned out to be insufficient with the XE262H cam profile. Many cam companies offer cam and spring packages designed to work together.  Run with the new Comp cam...  Run with the new Comp cam in place, the peak power numbers jumped to 403 hp at 5,000 rpm and an even 500 lb-ft of torque at a slightly higher 3,600 rpm. The mild XE262H cam improved the power production through the entire rev range, with no trade in low-speed power for the sizable jump at the top of the rev range.  Our final modification was...  Our final modification was to install a set of ported stock heads. Though the minimal porting could easily be duplicated at home, we had the gang at L&R Automotive perform a quick pocket port and valve job on the stock C8VE castings. Many Ford owners will take the standard head ports out to Cobra Jet size, but we refrained from going big on this mild application. The ports were simply fluffed up and the sharp edges removed, especially on the exhaust.  Most of the attention should...  Most of the attention should be paid to the exhaust port, as the intake already flowed fairly well.  Forget about port matching...  Forget about port matching the heads to a specific gasket and instead concentrate your efforts on the bowl and valve job. The bowl work was minimal, but we made sure to perform a three-angle valve job using the stock valves. The heads were also treated to a minimal surface cut to ensure proper sealing.  Off came the stock heads and...  Off came the stock heads and on went the ported stock heads from L&R. The heads were secured using stock head bolts and new head (and intake) gaskets from Fel Pro.  Admittedly, the freshly painted...  Admittedly, the freshly painted heads look somewhat out of place on the junkyard engine, but they offered decent power gains given the minimal work. The ported heads improved the power output from 403 hp and 500 lb-ft of torque to 437 hp and 507 lb-ft of torque. There’s plenty more power left in this 460, check back with us next month as we unleash the beast.  The power curve tells the...  The power curve tells the story, as we were successful in increasing the power output of the ’68 460 Ford by more than 110 hp. The only trade off associated with the modifications was the torque loss suffered below 3,000 rpm. This was a function of the factory intake manifold, as it was designed to enhance torque production very low in the rev range. Make sure to check hood clearance, as the Weiand dual-plane is more of a high-rise design than the factory manifold and may interfere with factory hoods. The gains were impressive given the mild cam specs and use of mildly ported stock heads. All told, we increased the peak power numbers from 349 hp and 492 lb-ft to 437 hp and 507 lb-ft of torque. Make sure to check back with us, as we intend to step these numbers up considerably in Part 2.
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